Outcomes of root canal treatment and restoration, implant-supported single crowns, fixed partial dentures, and extraction without replacement: A systematic review Mahmoud Torabinejad, DMD, MSD, PhD,a Patricia Anderson, MILS,b Jim Bader, DDS, MPH,c L. Jackson Brown, DDS, PhD,d Lie H. Chen, MPH,e Charles J. Goodacre, DDS, MSD,f Mathew T. Kattadiyil, DDS, MDS, MS,g Diana Kutsenko, DMD,h Jaime Lo- zada, DDS,i Rishi Patel, BDS,j Floyd Petersen, MPH,k Israel Put- erman, DMD,l and Shane N. White, BDentSc, MS, MA, PhDm School of Dentistry, and School of Public Health, Loma Linda University, Loma Linda, Calif; Dentistry Library, University of Michigan, Ann Arbor, Mich; School of Dentistry, University of North Carolina at Chapel Hill, Chapel Hill, NC; Health Policy Resources Center, American Dental Association, Chicago, Ill; University of California Los Angeles School of Dentistry, Los Angeles, Calif

Statement of problem. Dentists and patients are regularly confronted by a difficult treatment question: should a tooth be saved through root canal treatment and restoration (RCT), be extracted without any tooth replacement, be replaced with a fixed partial denture (FPD) or an implant-supported single crown (ISC)?

Purpose. The purpose of this systematic review was to compare the outcomes, benefits, and harms of endodontic care and restoration compared to extraction and placement of ISCs, FPDs, or extraction without tooth replacement.

Material and methods. Searches performed in MEDLINE, Cochrane, and EMBASE databases were enriched by hand searches, citation mining, and expert recommendation. Evidence tables were developed following quality and inclu- sion criteria assessment. Pooled and weighted mean success and survival rates, with associated confidence intervals, were calculated for single implant crowns, fixed partial dentures, and initial nonsurgical root canal treatments. Data related to extraction without tooth replacement and psychosocial outcomes were evaluated by a narrative review due to literature limitations.

aProfessor of Endodontics, School of Dentistry, Loma Linda University. bHead Librarian, Dentistry Library, University of Michigan. cResearch Professor, Department of Operative Dentistry, School of Dentistry, University of North Carolina at Chapel Hill. dAssociate Executive Director, Health Policy Resources Center, American Dental Association. eStatistical Programmer, Health Research Consulting Group, School of Public Health, Loma Linda University. f Professor of Restorative Dentistry and Dean, School of Dentistry, Loma Linda University. gAssociate Professor of Restorative Dentistry and Interim Director, Advanced Education Program in Prosthodontics, School of Dentistry, Loma Linda University. hResident, Postgraduate Endodontics, School of Dentistry, Loma Linda University. iProfessor and Graduate Program Director of Implant Dentistry, School of Dentistry, Loma Linda University. jResident, Advanced Education Program in Prosthodontics, School of Dentistry, Loma Linda University. kAssistant Professor, Health Research Consulting Group, Department of Epidemiology and Biostatistics, School of Public Health, Loma Linda University. lResident, Postgraduate Periodontics, School of Dentistry, Loma Linda University. mProfessor, University of California Los Angeles School of Dentistry. Torabinejad et al 286 Volume 98 Issue 4 Results. The 143 selected studies varied considerably in design, success definition, assessment methods, operator type, and sample size. Direct comparison of treatment types was extremely rare. Limited psychosocial data revealed the traumatic effect of loss of visible teeth. Economic data were largely absent. Success rates for ISCs were higher than for RCTs and FPDs, respectively; however, success criteria differed greatly among treatment types, rendering direct comparison of success rates futile. Long-term survival rates for ISCs and RCTs were similar and superior to those for FPDs.

Conclusions. Lack of comparative studies with similar outcomes criteria with comparable time intervals limited comparison of these treatments. ISC and RCT treatments resulted in superior long-term survival, compared to FPDs. Limited data suggested that extraction without replacement resulted in inferior psychosocial outcomes compared to alternatives. Long-term, prospective clinical trials with large sample sizes and clearly defined outcomes criteria are needed. (J Prosthet Dent 2007;98:285-311)

Clinical Implications Limited data suggested that extraction without replacement resulted in inferior psychosocial outcomes compared to alternatives of retention or replacement. Implant and endodontic treatments resulted in superior long-term survival, compared to fixed partial dentures. Success criteria differed greatly among treatment types, rendering direct comparison of success rates unhelpful. Therefore, priority in treatment planning should be given to tooth retention through root canal treatment or to replace- ment with an implant-supported single crown.

Preservation of the natural denti- affect specialists, general dentists, American Dental Association Foun- tion has long been a key dental thera- patients, employers who purchase in- dation request for proposals. peutic goal. The high survival rates surance packages, insurance compa- of osseointegrated dental implants nies, and policy makers.16 Treatment MATERIAL AND METHODS have created new treatment options. decisions must be based on scientific Dentists and patients are regularly study of clinical outcomes, including A systematic review was developed confronted by difficult treatment clinical, psychosocial, and economic following established guidelines.29 questions necessitating both quan- measures.2,17 Economic methods may Methodology included: formulating titative and qualitative responses.1,2 be usefully applied to healthcare out- review questions using a PICO (Pa- For example, should a tooth be saved comes questions, because they allow tient Population, Intervention, Com- through root canal treatment and res- measurement of costs and benefits to parison, and Outcome) framework; toration (RCT), be extracted without individual patients and to society in constructing a search strategy; defin- any tooth replacement, or be replaced general.18-26 Systematic review of the ing inclusion and exclusion criteria; with a fixed partial denture (FPD) or existing literature can provide an ob- locating studies; selecting studies; as- an implant-supported single crown jective synopsis of the best available sessing study quality; extracting data (ISC)? Considerations involved in se- evidence that can help dentists and and forming an evidence table; and lecting from among these 4 treatment their patients make these choices.27 interpretation. alternatives have been reviewed and Systematic reviews are inherently less discussed.3-9 However, direct compar- biased, more reliable, and more valid Formulating the review questions isons of outcomes are limited.10-13 The than narrative reviews.28,29 available reviews do not compare all The purpose of this study was to The PICO framework was used to of the available alternative treatments conduct a systematic review of the formulate the following 3 questions for a tooth with pulpal pathology, nor clinical, psychosocial, and economic for a systematic review of the existing do they consider all of the possible outcomes, as well as beneficial and literature. These 3 questions represent outcomes of such treatments.14,15 harmful effects, of initial nonsurgical an adaptation of 2 questions original- Evidence-based principles that endodontic care, compared to extrac- ly in the American Dental Association include identification of specific sci- tion and placement of an implant, Foundation request for proposals: (1) entific evidence, assessing its valid- fixed partial denture, or extraction In patients with periodontally sound ity, and using the “best” evidence to without tooth replacement. This proj- teeth that have pulpal and/or perira- inform patient care decisions, can ect was developed in response to an dicular pathosis, does initial nonsur- The Journal of Prosthetic Dentistry Torabinejad et al October 2007 287 gical root canal therapy, compared to (proceedings of conferences not listed pline, collaborative searching strate- extraction without replacement of the in MEDLINE, Cochrane, and EMBASE gies were developed among a librar- missing tooth, result in better (more databases, meetings, and lectures); ian, the subject expert, a consultant, beneficial) or worse (more harmful) studies without clinical, psychosocial, and the principal investigator. Each clinical and/or biological outcomes, or economic outcomes; and implant search began with selection of 10 or psychosocial outcomes, and econom- studies on completely edentulous pa- more sentinel articles. The articles ic outcomes? (2) Similarly, does root tients. were selected to represent the sorts of canal therapy, compared to extraction articles that should be retrieved by a and replacement of the missing tooth Search methodology good MEDLINE search for that topic. with a fixed partial denture, result in The sentinel articles were restricted to better or worse outcomes? And, (3) Electronic searches were per- the inclusion and exclusion criteria. Similarly, does root canal therapy, formed in MEDLINE, Cochrane, and The sentinel articles served as seed compared to extraction and replace- EMBASE databases, with the results articles to suggest appropriate MeSH ment of the missing tooth with an im- enriched by hand searches, citation (Medical Subject Headings) and free plant-supported restoration, result in mining, and expert recommendation. text terms for the searches.30 These better or worse outcomes? Hand searches involved reviewing the headings and terms were enriched by tables of contents for every issue of terms suggested and reviewed jointly Inclusion and exclusion criteria the most recent 2 years of the follow- by the information expert and the ing journal titles, which represented domain expert for that topic. For the Inclusion criteria included com- 50% of the total number of original final search strategies, the filters were parative or noncomparative, prospec- research articles in English from the combined with primary clinical out- tive or retrospective, longitudinal data past 5 years for the ISC, FPD, and comes; the Rochester/Miner etiology related to clinical, biological, psycho- RCT topics: American Journal of Dentist- and prognosis filters enriched with se- social, and economic outcomes, as ry, Clinical Implant Dentistry and Related lected research methodology terms, well as beneficial or harmful effects of Research, Clinical Oral Implants Research, and the limits and/or exclusion cri- saving teeth by root canal treatment Dental Materials, Dental Traumatology, teria (Fig. 4).31,32 Following the initial and/or alternative treatments. Inclu- Implant Dentistry, International Endodon- search strategies on primary clinical sion criteria for paper review includ- tic Journal, International Journal of Oral outcomes, a second search was per- ed: articles published in English from and Maxillofacial Implants, International formed for each of the ISC, FPD, and January 1966 to September 2006; Journal of Periodontics and Restorative RCT disciplines to retrieve results on adult subjects; secondary teeth; ini- Dentistry, International Journal of Prosth- psychosocial outcomes (Fig. 5). tial treatment; implant-supported odontics, Journal of Dentistry, Journal of Search strategies were reviewed single crowns; threaded, cylindrical Endodontics, Journal of Periodontology, for quality by verifying the inclusion implants regardless of surface type; The Journal of Prosthetic Dentistry, Jour- of the sentinel articles. If any sentinel minimum of 2-year follow-up (RCT - nal of Oral and Maxillofacial Surgery, articles were not included, the rea- from obturation; ISC - from implant Journal of Oral Rehabilitation, Operative son for the loss was identified, and placement; FPD - from cementation) Dentistry, Oral Surgery Oral Medicine the search process was reviewed and with treatment units described as be- Oral Pathology Oral Radiology and End- revised by the domain expert and ing individual ISCs, short-span FPDs odontics, and Quintessence International. information expert in consultation of 3 to 4 units, and RCT teeth (not The citation mining and expert with the principal investigators. The individual roots); with a minimum of recommendation process incorpo- revised search was then tested again 25 treatments (not patients). Publi- rated relevant materials that may not for validity. The abstracts of these cation in a peer-reviewed journal was appear in a MEDLINE search on the articles were then reviewed based on not an inclusion criterion, because the topic, such as book chapters or re- these inclusion and exclusion crite- best available evidence or data is not view articles. External experts were ria. Valid systematic search strategies always found therein. For example, consulted to recommend additional for the effects of extraction without authors are often directly contacted articles or books for review. Other da- tooth replacement and for economic for their raw data during the system- tabase searches, including Cochrane outcomes were not achieved due to atic review process.27-29 and EMBASE, were designed as per- limitations of the available literature The exclusion criteria consisted of mutations of the successful MEDLINE and indexing terms. Therefore, these studies that failed to meet the above search strategy. topics were limited to hand searches, inclusion criteria; RCTs due to trau- Search strategies were developed citation mining, and expert recom- ma; treatment modalities not cur- for 3 disciplines: implants, fixed mendations. rently being used; moderate or severe prosthodontics, and endodontics periodontal disease; grey literature (Figs. 1 through 3). For each disci- Torabinejad et al 288 Volume 98 Issue 4

(((exp Dental Implants/ or exp Dental Implantation/ or Dental Prosthesis, Implant-Supported/ or Osseointegration/ or Implants, Experimental/ or “Prostheses and Implants”/) and (exp Jaw/ or exp Jaw Diseases/ or exp Jaw Abnormalities/ or exp Mouth, Edentulous/)) or (exp Dental Implants/ or exp Dental Implantation/ or Dental Prosthesis, Implant-Supported/)) or (((((dental or oral or maxillofacial or jaw) adj3 implant$1).mp. or osseointegrat:.mp. or (peri-implant: or periimplant:).mp. or “implant-supported”.mp. or (implant adj (tooth or tissue) adj support:).mp. or (implantology or implantologia or implantologie).mp. or ((hollow adj (screw$2 or cylinder$1)) or (HS or HC)).mp.) and (exp Jaw/ or exp Jaw Diseases/ or exp Jaw Abnormalities/ or exp Mouth, Edentulous/)) or (surgi: adj3 dental adj3 prosthe:).mp. or ((single-tooth or subperiosteal or endosseous or occlusal or periapical) adj3 implant:).mp.) or ((branemark.ti,ab. or 3i.mp. or Anthogyr.mp. or “Astra Tech”. mp. or Bicon.mp. or BioHorizons.mp. or BLB.mp. or Calcitek.mp. or conical.mp. or transmucosal.mp. or “conventional cast”.mp. or (friatec: or friadent or frialit:).mp. or Impla-Med.mp. or IMTEC.mp. or IMZ.mp. or ITI. mp. or “laser-welded”.mp. or Lifecore.mp. or ((Mk or Mark) adj (II or III or IV)).mp. or (MKII or MKIII or MKIV). mp. or Micro-Lok.mp. or “morse taper”.mp. or novum.mp. or Omnilock.mp. or Paragon.mp. or Restore.mp. or screw-shaped.mp. or “Screw Vent”.mp. or self-tapping.mp. or splinted.mp. or Stargrip.mp. or Steri-Oss.mp. or Sulzer.ti,ab. or TBR.mp. or Tenax.mp. or TiUnite.mp. or titanium.mp. or unsplinted.mp. or zygomaticus.mp. or ((dental or implant) adj (protocol or system or framework)).mp.) and (exp Jaw/ or exp Jaw Diseases/ or exp Jaw Abnormalities/ or exp Mouth, Edentulous/) and ((dental or implant) adj (protocol or system or framework)). mp.) and (Clinical Protocols/ or exp Clinical trials/ or exp Patient Care Management/ or Patient Selection/ or Practice Guidelines/ or clinic:.mp. or (recall adj3 appointment$1).mp. or ((patient or research) adj3 (recruitment or selection)).mp. or (selection adj3 (criteria or treatment or subject$1)).mp. or (treatment adj protocol$1). mp. or ra.fs. or radiograph:.mp. or ah.fs. or histolog:.mp. or (nonsurg: or non-surg:).mp. or exp “Quality of Life”/ or ((surviv$3 or fail$3 or success$3) adj rate).mp. or “Denture Retention”/ or Dental prosthesis retention/ or exp Wound Healing/) and (exp Disease progression/ or exp Morbidity/ or exp Mortality/ or exp “Outcome assessment (health care)”/ or exp Patient satisfaction/ or exp Prognosis/ or exp Survival analysis/ or exp Time factors/ or exp Treatment outcome/ or ((beneficial or harmful) adj3 effect$).mp. or co.fs. or course.mp. or (inception adj cohort$1).mp. or (natural adj history).mp. or outcome$1.mp. or predict$.mp. or prognos$.mp. or surviv$3.mp. or fail$5.mp. or longevity.mp. or durability.mp. or succes:.mp. or random$.ti,ab. or predispos$. ti,ab. or causa$.ti,ab. or exp Case-control studies/ or (case$1 adj control$).ti,ab. or exp Cohort studies/ or exp “Comparative study”/ or exp Epidemiological Studies/ or odds ratio/ or (odds adj ratio$1).ti,ab. or exp Risk/ or risk$.ti,ab. or Meta-analysis/ or Meta-analysis.pt. or practice guideline.pt. or exp Clinical Trials/ or (randomized controlled trial or controlled clinical trial).pt. or random$.ti,ab. or (systematic adj review$1).mp. or Retreatment/ or Recurrence/ or (retreat: or revis:).mp.) 1 Search strategy for single tooth implant studies, without limits.

(((exp Prosthodontics/ or exp Oral Surgical Procedures, Preprosthetic/ or exp Maxillofacial Prosthesis Implantation/ or exp Tooth Replantation/) or ((exp “Prostheses and Implants”/ or (prosthes: or prosthet: or prostho:).mp.) and exp stomatognathic system/) or ((dentur:.mp. or ((dent: or palat$3 or tooth or teeth or molar) adj5 (abut: or clasp$1 or restor: or crown$1 or post$1 or veneer$1)).mp.) and exp stomatognathic system/) or ((resin adj bonded adj3 prosthes:).mp. or pontic$1.mp. or ((conservative or rochette or maryland) adj bridge$1).mp. or ((cantilever or conservative) adj5 (“fixed partial denture” or FPD)).mp. or ((“fixed partial denture” or FPD or bridge or abutment) adj3 retainer).mp. or ((gold or ceramic: or porcelain or resin or PFM or metal: or “all metal” or “all ceramic” or “implant supported” or “implant retained” or “base metal” or “high noble” or alloy) adj5 (crown or restoration)).mp.)) and (Clinical Protocols/ or exp Clinical trials/ or exp Patient Care Management/ or Patient Selection/ or Practice Guidelines/ or clinic:.mp. or (recall adj3 appointment$1). mp. or ((patient or research) adj3 (recruitment or selection)).mp. or (selection adj3 (criteria or treatment or subject$1)).mp. or (treatment adj protocol$1).mp. or ra.fs. or radiograph:.mp. or ah.fs. or histolog:.mp. or (nonsurg: or non-surg:).mp. or exp “Quality of Life”/ or ((surviv$3 or fail$3 or success$3) adj rate).mp. or “Denture Retention”/ or Dental prosthesis retention/ or exp Wound Healing/) and (exp Disease progression/ or exp Morbidity/ or exp Mortality/ or exp “Outcome assessment (health care)”/ or exp Patient satisfaction/ or exp Prognosis/ or exp Survival analysis/ or exp Time factors/ or exp Treatment outcome/ or ((beneficial or harmful) adj3 effect$).mp. or co.fs. or course.mp. or (inception adj cohort$1).mp. or (natural adj history).mp. or outcome$1.mp. or predict$.mp. or prognos$.mp. or surviv$3.mp. or fail$5.mp. or longevity.mp. or durability. mp. or succes:.mp. or random$.ti,ab. or predispos$.ti,ab. or causa$.ti,ab. or exp Case-control studies/ or (case$1 adj control$).ti,ab. or exp Cohort studies/ or exp “Comparative study”/ or exp Epidemiological Studies/ or odds ratio/ or (odds adj ratio$1).ti,ab. or exp Risk/ or risk$.ti,ab. or Meta-analysis/ or Meta-analysis.pt. or practice guideline.pt. or exp Clinical Trials/ or (randomized controlled trial or controlled clinical trial).pt. or random$. ti,ab. or (systematic adj review$1).mp. or Retreatment/ or Recurrence/ or (retreat: or revis:).mp.) and (single:.mp. or immediate:.mp. or bound:.mp. or pontic:.mp. or (abut: adj (teeth or tooth)).mp.)) 2 Search strategy for fixed partial denture studies, without limits. The Journal of Prosthetic Dentistry Torabinejad et al October 2007 289

((exp Endodontics/ or exp Dental Pulp Diseases/ or exp Periapical Diseases/ or exp “Root Canal Filling Materials”/ or Dental Pulp Test/ or Dental Pulp/ or Dental Pulp Cavity/) or ((“root canal”.mp. or apicectom:.mp. or apicoectom:.mp. or (dead adj3 (teeth or tooth)).mp. or (dental adj3 pulp:).mp. or endodont:.mp. or endont:. mp. or endosonic.mp. or ((lateral or vertical) adj condensation).mp. or ((non-vital or nonvital) adj3 (teeth or tooth)).mp. or obtura.mp. or obturation.mp. or obturate.mp. or (pulp adj3 (capping or therap: or extirpation:)). mp. or (pulp adj (canal$1 or chamber$1)).mp. or pulpectomy.mp. or pulpotomy.mp. or replantation.mp. or (“root” adj end adj5 fill:).mp. or ((silver or gutta) adj3 (percha or balata)).mp. or (silver adj (cone$1 or point$1)). mp. or thermafil.mp. or trans-polyisoprene.mp. or transpolyisoprene.mp. or ultrafil.mp.) or ((periradicular or radicular or periapical or apical).mp. and (exp tooth/ or exp tooth components/))) not (*Apicoectomy/ or *Dental Implantation, Endosseous, Endodontic/ or *Retrograde Obturation/ or *Tooth Replantation/)) and (Clinical Protocols/ or exp Clinical trials/ or exp Patient Care Management/ or Patient Selection/ or Practice Guidelines/ or clinic:.mp. or (recall adj3 appointment$1).mp. or ((patient or research) adj3 (recruitment or selection)).mp. or (selection adj3 (criteria or treatment or subject$1)).mp. or (treatment adj protocol$1).mp. or ra.fs. or radiograph:.mp. or ah.fs. or histolog:.mp. or (nonsurg: or non-surg:).mp.) and (exp Disease progression/ or exp Morbidity/ or exp Mortality/ or exp “Outcome assessment (health care)”/ or exp Patient satisfaction/ or exp Prognosis/ or exp Survival analysis/ or exp Time factors/ or exp Treatment outcome/ or ((beneficial or harmful) adj3 effect$).mp. or co.fs. or course.mp. or (inception adj cohort$1).mp. or (natural adj history).mp. or outcome$1.mp. or predict$.mp. or prognos$.mp. or surviv$3.mp. or fail$5.mp. or longevity.mp. or durability. mp. or succes:.mp. or random$.ti,ab. or predispos$.ti,ab. or causa$.ti,ab. or exp Case-control studies/ or (case$1 adj control$).ti,ab. or exp Cohort studies/ or exp “Comparative study”/ or exp Epidemiological Studies/ or odds ratio/ or (odds adj ratio$1).ti,ab. or exp Risk/ or risk$.ti,ab. or Meta-analysis/ or Meta-analysis.pt. or practice guideline.pt. or exp Clinical Trials/ or (randomized controlled trial or controlled clinical trial).pt. or random$. ti,ab. or (systematic adj review$1).mp. or Retreatment/ or Recurrence/ or (retreat: or revis:).mp.) 3 Search strategy for endodontic studies, without limits.

([N] not ((Dentition, Primary/ or (immatur: adj3 (teeth or tooth)).mp. or (open adj3 (apex or apices or apexes)). mp. or blunderbuss.mp. or limit [N] to (preschool child <2 to 5 years> or child <6 to 12 years>)) not (Dentition, Mixed/ or Dentition, Permanent/ or Adolescent/ or (mature adj3 (teeth or tooth)).mp. or (closed adj3 (apex or apices or apexes)).mp. or limit [N] to all adult <19 plus years>)) not (Animal/ not Human/)) limit [X] to English language

NOTE: The above formula describes the limits applied to each of the three topic searches where [N] represents the final set number of the search to which the limits are applied, and [X] represents the current set containing all limits. 4 Search strategy; limits applied to all topic searches.

([X] and (Dental anxiety/ or odontophobia.mp. or ((dental or dentist:) adj5 (anxi: or phob: or fear)).mp. or ((Fear/ or Anxiety/) and (exp Dentistry/ or exp Stomatognathic System/ or exp Stomatognathic diseases/)) or (“Quality of Life”/ or exp Consumer Satisfaction/ or Attitude/ or ((consumer$1 or patient$1) adj5 (satisf: or preference$1 or accept:)).mp.))

NOTE: The above formula describes each of the three searches for psychology outcomes, where [X] represents the topic search complete with all limits. 5 Search strategy for psychosocial outcomes, applied to all topic searches.

Study selection full-text reviewed by the 3 teams inde- based on a predetermined protocol pendently in the second stage of the for resolving disagreements between First, 3 teams composed of 6 in- process. An independent committee reviewers.17 The independent commit- vestigators (2 from each discipline) of experts, 2 from each discipline, re- tee of experts approved the final list. independently screened the titles and viewed the final list to ensure that the abstracts of all articles identified in inclusion criteria made sense, given Study quality rating the electronic and hand searches for the existing literature, and that key each of the 3 disciplines. Articles that studies were not missed. A log of ex- A 31-question data abstraction did not meet the search criteria were cluded studies and the reasons for ex- form was developed. The questions excluded upon reviewers’ agreement. clusion was also developed. In case of related to basic information includ- Second, all remaining articles were disagreement, consensus was reached ing: study type (such as prospec- Torabinejad et al 290 Volume 98 Issue 4 tive/retrospective and clinical trial), systems used, general lack of com- limitations included marked variabil- number of patients, number of units monality, and often limited descrip- ity in success criteria, variation in or (teeth/implants/prostheses), study tion, it was not possible to usefully absence of the reporting of complica- setting, age range of patients, length and succinctly tabulate the success tions and adverse effects, consider- of follow-up, and specific outcomes criteria used. The data abstraction able variation in follow-up time, lack and data regarding the types of com- form was expanded to allow detailed of life table reporting, and lack of di- plications encountered during and af- objective data such as number of pa- rect comparison of treatment modes. ter these procedures.33 This form was tients and teeth/implants/prostheses, For comparative purposes, clinical also used to assess internal validity study design, primary and secondary outcomes were grouped into 3 fol- by recording information about ele- outcomes, and population sampled low-up intervals: 2-4 year, 4-6 year, ments of randomization, concealment to be assembled for selected studies. and over 6 years. For each discipline of treatment allocation, blinding, The independent committee of experts and follow-up interval, individual and the handling of patient attrition. (2 from each discipline) reviewed and studies were displayed in a Forest plot From the abstracted information, an approved the final evidence tables. with Wilson Score 95% confidence overall study quality rating score was intervals. The Wilson Score method developed. Data analysis is a refinement of the simple asymp- Each paper was given a quality totic method designed to provide score with a maximum possible score Quantitative and qualitative meth- enhanced coverage and increased of 17 points.34,35 The evaluators as- ods were used to integrate the evi- aberration avoidance.38 Meta-analy- signed points as follows: random- dence without necessarily being ses produced pooled point and 95% ized clinical trial (4); nonrandomized guided by a specific predetermined confidence interval estimates of suc- clinical trial (3); clinical trial with no protocol, so as to accommodate the cess and survival using the DerSimo- controls or cohort (2); case-control strengths and weaknesses of the col- nian-Laird random effects pooling or case series (2). One point was lected data and to best provide clini- method, as well as by simple weight- given for each of the following: total cally relevant conclusions. The data ing. This pooling method is appropri- number of enrolled subjects stated; were analyzed by deciding whether ate for comparison of heterogeneous sample size predetermined; operator and what data to combine; measur- data, but less well suited to large and experience stated; demographic de- ing the statistical heterogeneity of the disparate sample sizes. Conversely, scription included; treatment proce- data using Cochrane Q and I2 statis- weighting is unsuited to strongly het- dures completely described; evaluator tics; assessing the potential for bias; erogeneous data, but is well suited to different from the operator; complete and presenting the results in the form large and disparate sample sizes. description of subject loss; treatment of tables and figures that compare the Although papers containing psy- complications described; measure- included studies.36,37 The Cochrane Q chosocial and economic outcomes ments standardized; evaluation meth- statistic is a simple, widely used esti- did meet the inclusion criteria, their ods clearly described; intention to mate of between-study variability, but variability precluded meaningful sys- treat stated; and the description and it has poor power when few studies tematic abstraction and analysis. appropriateness of statistical tech- are included, and excessive power to Therefore, psychosocial and econom- niques and stratification. detect clinically unimportant hetero- ic outcome data were limited to nar- geneity when many studies are includ- rative review. Outcomes of the effects Data extraction for the evidence ed. The I2 statistic is a useful indicator of extraction without replacement table of the proportion of total variation in were even more limited, again neces- study estimates that is due to hetero- sitating narrative review. Interpreta- Each team independently extract- geneity. tion of data relating to the trauma of ed data and created a table of evidence Data abstraction, analysis, and in- extraction itself was considered to be from articles that met the validity cri- terpretation were severely constrained beyond the scope of this review. teria for each discipline. Within each by limitations in the existing literature. team, the 3 reviewers independently Success and survival rates sometimes RESULTS assessed the studies, then discussion had to be calculated by the reviewers and consensus was used to resolve either because they were not directly Description of the existing literature any disagreements. Interpretation of provided, or because only a particular outcome data, classification of data data subset met the inclusion criteria. Initial electronic and manual as to success or survival, and the type In some instances, it was not clear if searches identified 4361 ISC studies, of study were subsequently verified by the outcome measures were crude or 3340 FPD studies, and 5346 RCT 2 statisticians. Due to great dispari- cumulative. Thus, crude and cumula- studies. Following title and abstract ties among criteria, the many unique tive estimates were combined. Other screening, full texts for 327 ISC stud- The Journal of Prosthetic Dentistry Torabinejad et al October 2007 291 ies, 229 FPD studies, and 347 RCT recently by ISC studies in 1993. Few comes tended to be more frequently studies were obtained. Following articles comparing treatment modes described by more rigorous studies full-text review for clinical outcomes, were located; these were listed in Ta- than the other disciplines. There were 46 ISC papers (Table I), 31 FPD pa- ble V. few randomized controlled studies pers (Table II), and 24 RCT papers Major sources of heterogeneity within treatment types, only 1 for (Table III) were included. Sixteen ar- included reporting of results from ISCs, 1 for FPDs, and 3 for RCTs. ticles regarding the effects of tooth differing areas of the mouth; com- Only 4 ISC, 4 FPD, and 7 RCT papers extraction without replacement were parison of differing materials and reported the use of controls. Where identified (Table IV). In addition, 27 techniques within studies; differ- comparisons were made, they were studies regarding psychosocial effects ing follow-up times; reporting units, generally among various techniques of these treatment types were identi- teeth, implants, or crowns; differing or materials. Overall, less rigorous fied (Table V). Few articles addressing outcomes measures; differences in case-series analyses dominated the economic outcomes were identified; operator type; and major variations included articles; they comprised 64% several of these addressed psychoso- in patient selection or sample size. of ISC articles, 71% of FPD articles, cial issues, and are all included within Examination of the Cochrane Q and and 40% of RCT articles. Prospective Table V. Root canal treatment stud- I2 revealed that all testable strata, ex- designs were included in 62% of ISC, ies appeared to be the most mature cept for implants at 4-6 years, were 38% of FPD, and 66% of RCT stud- outcomes literature with usable stud- significantly heterogeneous. ies. Only 13% of the ISC studies had ies first appearing in 1979, followed Study design varied among the 3 an evaluator that was different than by FPD studies in 1984, and most types of treatment. Endodontic out- the operator. In contrast, FPD and

Table I. Evidence table summary for single tooth replacement by implant-supported single crowns (ISCs). Pooled and weighted success and survival rates, with their associated 95% confidence intervals (CI), were calculated using DerSimonian-Laird random effects model

ISC SUCCESS Year Time in Sample Number Success Wilson Score Quality Authors Published Years Size Successful Rate in % Interval Score

Schmitt and Zarb69 1993 2-4 40 40 100 95-96 6 Karlsson et al70 1997 2-4 47 47 100 96-97 8 Polizzi et al71 2000 2-4 38 35 92 80-96 4 Norton72 2004 2-4 28 27 96 85-97 9 Tsirlis73 2005 2-4 43 43 100 95-97 5 Zarone et al74 2006 2-4 34 33 97 87-97 9 Pooled Success Rate (95% CI) 98 (95-99) Weighted Success Rate (95% CI) 99 (96-100)

Henry et al75 1996 4-6 107 104 97 93-99 7 Scheller et al76 1998 4-6 99 95 96 90-98 10 Polizzi et al77 1999 4-6 30 28 93 80-96 8 Gibbard and Zarb78 2002 4-6 30 30 100 93-95 9 Mayer et al79 2002 4-6 71 70 99 93-99 8 Prosper et al80 2003 4-6 111 108 97 93-99 9 Covani et al81 2004 4-6 163 156 96 92-98 10 Nentwig82 2004 4-6 943 934 99 98-99 3 Anner et al83 2005 4-6 45 45 100 95-97 5 Wennstrom et al84 2005 4-6 45 44 98 90-98 10 Pooled Success Rate (95% CI) 97 (96-98) Weighted Success Rate* (95% CI) 98 (97-99)

Fugazzotto et al85 2004 6+ 979 930 95 94-96 4 Levin et al86 2005 6+ 51 47 93 83-96 7 Pooled Success Rate (95% CI) 95 (93-96) Weighted Success Rate (95% CI) 95 (93-97)

Torabinejad et al 292 Volume 98 Issue 4

Table I. continued (2 of 2) Evidence table summary for single tooth replacement by implant-supported single crowns (ISCs). Pooled and weighted success and survival rates, with their associated 95% confidence intervals (CI), were cal- culated using DerSimonian-Laird random effects model

ISC SURVIVAL Year Time in Sample Number Survival Wilson Score Quality Authors Published Years Size Surviving Rate in % Interval Score

Jemt and Pettersson87 1993 2-4 70 69 99 93-99 8 Cordioli et al88 1994 2-4 67 64 95 88-98 7 Levine et al89 1999 2-4 157 150 96 92-98 7 Moberg et al90 1999 2-4 30 29 97 86-97 7 Wannfors and Smedberg91 1999 2-4 80 79 99 94-99 7 Johnson and Persson92 2000 2-4 59 58 98 92-98 8 Rodriguez et al9393 2000 2-4 209 205 98 95-99 5 Mangano and Bartolucci94 2001 2-4 80 77 96 90-98 7 Krennmair et al95 2002 2-4 146 142 97 94-99 8 Norton and Wilson96 2002 2-4 40 36 89 76-94 6 Andersson et al97 2003 2-4 42 41 98 89-98 8 Groisman et al98 2003 2-4 92 86 94 87-97 6 Block et al99 2004 2-4 74 70 95 97-97 5 Ottoni et al100 2005 2-4 46 35 76 63-85 9 Schropp et al101 2005 2-4 46 43 94 84-97 8 Pooled Survival Rate (95% CI) 95 (93-97) Weighted Survival Rate (95% CI) 96 (94-97)

Malevez et al102 1996 4-6 84 82 98 92-99 3 Andersson et al103 1998 4-6 38 38 100 95-96 9 Andersson et al104 1999 4-6 65 64 99 93-99 8 Romanos and Nentwig105 2002 4-6 58 56 97 89-98 1 Meriscke-Stern et al106 2002 4-6 109 108 99 96-99 8 Morris et al107 2003 4-6 251 238 95 92-97 7 Covani et al81 2004 4-6 163 158 97 93-98 10 Dhanrajani and Al-Rafee108 2004 4-6 147 138 94 89-96 6 Pooled Survival Rate (95% CI) 97 (95-98) Weighted Survival Rate (95% CI) 97 (95-98)

Scholander109 1999 6+ 259 254 98 96-99 9 Bianco et al110 2000 6+ 252 242 96 93-98 7 Bianchi and Sanfilippo111 2004 6+ 116 116 100 98-99 10 Doring et al112 2004 6+ 275 270 98 96-99 3 Vigolo et al113 2004 6+ 192 182 95 91-97 7 Pjetursson et al114 2005 6+ 214 199 93 89-96 5 Pooled Survival Rate (95% CI) 97 (95-99) Weighted Survival Rate (95% CI) 97 (96-98)

The Journal of Prosthetic Dentistry Torabinejad et al October 2007 293

Table II. Evidence table summary for single tooth replacement by fixed partial dentures (FPDs). Pooled and weight- ed success and survival rates, with their associated 95% confidence intervals (CI), were calculated using DerSimonian- Laird random effects model

FPD SUCCESS Year Time in Sample Number Success Wilson Score Quality Authors Published Years Size Successful Rate in % Interval Score

Eshleman et al115 1984 2-4 39 33 85 71-92 4 Cheung et al116 1990 2-4 169 134 79 73-85 10 Olin117 1991 2-4 103 90 87 80-92 6 Kellett et al118 1994 2-4 54 26 49 36-61 9 Verzijden et al119 1994 2-4 201 139 69 63-75 11 Hussey and Linden120 1996 2-4 142 125 88 82-92 7 Sorensen et al121 1998 2-4 61 41 67 55-77 6 Botelho et al122 2002 2-4 82 78 95 89-98 9 Pooled Success Rate (95% CI) 79 (69-87) Weighted Success Rate (95% CI) 78 (76-81)

Reuter and Brose123 1984 4-6 121 104 86 79-91 7 Hansson and Moberg124 1992 4-6 34 32 93 81-97 8 De Kanter et al125 1998 4-6 210 111 53 46-60 5 Walter et al126 1999 4-6 47 45 95 85-97 12 Chai et al125 2005 4-6 210 172 82 77-87 12 Oginni128 2005 4-6 76 54 71 60-80 7 Wolfart et al129 2005 4-6 81 75 93 85-96 12 Marquardt and Strub130 2006 4-6 31 25 81 65-90 6 Pooled Success Rate (95% CI) 82 (71-91) Weighted Success Rate (95% CI) 76 (74-79)

Karlsson131 1986 6+ 238 221 93 89-96 6 Valderhaug132 1991 6+ 108 82 76 67-83 9 Priest133 1995 6+ 77 47 61 50-71 4 Keschbaum et al134 1996 6+ 1637 1310 80 78-82 5 Samama135 1996 6+ 145 120 83 76-88 2 Libby136 1997 6+ 89 76 85 77-91 3 Probster and Henrich137 1997 6+ 325 195 60 55-65 8 Behr et al138 1998 6+ 120 74 62 53-70 9 Shugars et al139 1998 6+ 124 117 94 89-97 5 Hochman et al140 2003 6+ 49 43 88 77-94 8 Holm et al141 2003 6+ 99 83 84 76-90 8 Olsson et al142 2003 6+ 42 35 83 70-91 9 Walton143 2003 6+ 515 474 92 89-94 5 De Backer et al144 2006 6+ 134 98 73 65-80 8 Pooled Success Rate (95% CI) 81 (74-86) Weighted Success Rate (95% CI) 80 (79-82)

FPD SURVIVAL Year Time in Sample Number Survival Wilson Score Quality Authors Published Years Size Surviving Rate in % Interval Score

Hussey and Linden120 1996 2-4 142 133 94 89-97 7 Barrack and Bretz145 1993 4-6 127 118 93 87-96 7 Keschbaum et al134 1996 6+ 1637 1342 82 80-84 5

Torabinejad et al 294 Volume 98 Issue 4

Table III. Evidence table summary for tooth retention by root canal treatment (RCT). Pooled and weighted suc- cess and survival rates, with their associated 95% confidence intervals (CI), were calculated using DerSimonian-Laird random effects model

RCT SUCCESS Year Time in Sample Number Success Wilson Score Quality Authors Published Years Size Successful Rate in % Interval Score

Ashkenaz et al146 1979 2-4 58 57 98 92-98 9 Rudner and Oilet147 1981 2-4 104 95 91 85-95 4 Oliet148 1983 2-4 338 301 89 85-92 9 Teo et al149 1986 2-4 385 350 91 87-93 10 Michnowicz et al150 1989 2-4 50 48 96 87-98 11 Benenati and Khajotia151 2002 2-4 29 28 97 85-97 11 Travassos et al152 2003 2-4 397 341 86 82-89 11 Field et al153 2004 2-4 223 198 89 85-93 11 Peters et al154 2004 2-4 263 229 87 82-90 12 Chu et al155 2005 2-4 85 68 80 71-87 11 Gagliani et al156 2006 2-4 122 110 90 84-94 10 Gesi et al157 2006 2-4 256 238 93 90-96 12 Pooled Success Rate (95% CI) 90 (88-92) Weighted Success Rate (95% CI) 89 (88-91)

Weiger et al158 2000 4-6 73 69 94 87-97 13 Friedman et al159 2003 4-6 405 393 97 95-98 12 Farzaneh et al160 2004 4-6 122 115 94 89-97 13 Marquis et al161 2006 4-6 132 114 86 79-90 11 Pooled Success Rate (95% CI) 93 (87-97) Weighted Success Rate (95% CI) 94 (92-96)

Stoll et al162 2005 6+ 595 506 85 82-88 10 Doyle et al163 2006 6+ 196 161 82 76-97 9 Pooled Success Rate (95% CI) 84 (82-87) Weighted Success Rate (95% CI) 84 (81-87)

RCT SURVIVAL Year Time in Sample Number Survival Wilson Score Quality Authors Published Years Size Surviving Rate in % Interval Score

Lazarski MP et al164 2001 2-4 44,613 41,936 94 94-95 11 Waltimo et al165 2001 4-6 204 194 95 91-97 11 Alley et al166 2004 4-6 350 326 93 90-95 9 Pooled Survival Rate (95% CI) 94 (92-96) Weighted Survival Rate (95% CI) 94 (91-96)

Aquilino and Kaplan167 2002 6+ 129 115 89 83-93 10 Dammaschke et al168 2003 6+ 190 162 85 79-89 11 Salehrabi and Rotstein169 2004 6+ 1,462,936 1,419,048 97 97-97 9 Doyle et al163 2006 6+ 196 184 94 90-96 9 Pooled Survival Rate (95% CI) 92 (84-97) Weighted Survival Rate (95% CI) 97 (97-97)

The Journal of Prosthetic Dentistry Torabinejad et al October 2007 295

Table IV. Evidence table for effects of tooth loss without replacement Authors Year Field of Study Study Type Sample Relevant Findings

Kayser170 1981 Oral function Cross-sectional 118 Four or more remaining pairs of occluding patients posterior teeth provided adequate oral function. Witter et al171 1987 Tooth migration in Cross-sectional 132 Tooth migration occurred in shortened dental shortened dental arches patients arches, but within acceptable levels. Oosterhaven 1989 Perception of dental Cross-sectional 74 Missing front teeth caused less positive feelings, et al172 appearance, missing teeth patients more negative feelings, and strongly affected daily life activities. Witter et al173 1990 Oral comfort in shortened Cross-sectional 171 Few patients with shortened dental arches reported dental arches patients impaired masticatory or esthetic complaints. Haugejordan 1993 Adjustment to cope Cross-sectional 284 Losing a tooth required a significant period of et al174 with dental life events responses adjustment and was likened to “trouble with relatives” in severity. Witter et al175 1994 Function and comfort in Longitudinal 107 Shortened dental arches are not risk factors for shortened dental arches 6 years patients craniomandibular dysfunction or oral discomfort. Shugars et al139 1998 Survival of teeth adjacent Retrospective 569 Untreated bounded edentulous spaces rarely to posterior spaces 6-14 years spaces resulted in loss of adjacent teeth; FPD treatment slightly improved survival rates. Shugars et al176 2000 Nonreplacement of missing Retrospective 126 Effects of a bounded edentulous space on posterior teeth 1-10 years patients movement and bone height of adjacent teeth were minimal. Witter et al177 2001 Occlusal stability in Retrospective 146 Shortened dental arches can provide long-term shortened dental arches 9 years patients occlusal stability; changes were self-limiting. Gragg et al178 2001 Tooth movement adjacent Retrospective 116 Space loss was less than 1 mm in the first year to posterior spaces 1-8 years spaces after extraction; movement after the first 2 years was minor. Davis et al179 2001 Emotional effects of tooth Cross-sectional 91 Emotional effects of tooth loss were common; loss in partially dentate responses confidence, dietary choice, food enjoyment, and social activities were affected. Aquilino et al180 2001 Survival of teeth adjacent Retrospective 317 Teeth adjacent to spaces restored with FPDs to posterior spaces 10 years patients had slightly higher 10-year survival estimates than those that remained untreated. Sarita et al181 2003 Temporomandibular disorders Cross-sectional 850 Distinct from absence of posterior support, in shortened dental arches patients shortened dental arches did not provoke temporomandibular disorders. Hattori et al182 2003 Joint and tooth loads in Laboratory 5 No evidence that experimentally temporarily shortened dental arches patients shortened dental arches caused overloading of joints and teeth. Sarita et al183 2003 Masticatory ability in Cross-sectional 850 Slightly or moderately shortened dental arches shortened dental arches responses provided sufficient masticatory ability and few complaints. Wolfart et al184 2005 Oral health life quality in Prospective 34 Patients with shortened dental arches reported shortened dental arches 1 year patients good dental treatment satisfaction and oral health related quality of life.

Torabinejad et al 296 Volume 98 Issue 4

Table V. Evidence table for psychosocial effects of implant-supported single crowns, fixed partial denture, and root canal therapies Authors Year Field of Study Study Type Sample Relevant Findings

Barbakow 1980 RCT; outcomes Prospective 566 teeth Vast majority of the teeth had some form of preoperative et al185 0-9 years pain. Wong and 1991 RCT and oral surgery; Cross-sectional 349 responses Anxiety scores classified RCT and oral surgery to high Lytle186 anxiety comparison anxiety; experience of RCT reduced anxiety. Ekfeldt187 1994 ISC; outcomes Retrospective 77 patients Large majority of patients rated function and willingness 14-55 months 94 implants to be treated again positively, smaller majority rated appearance and number of complications as highly; dentists ranked appearance lower. Complications were common. Andersson188 1995 ISC; outcomes Prospective 91 subjects Patients and dentists described all crowns as having good 2-3 years 102 implants esthetics. Lobb et al189 1996 RCT; patient perception Longitudinal 165 responses Approximately 20% of patients reported problems, mostly of problems 1 year pain and restorative, but most did not seek a response; extremely high willingness to repeat treatment, but pain and expense were deterrents. Andersson 1998 ISC; outcomes Prospective 38 patients Two of 38 crowns were considered esthetically et al103 1-5 years 38 implants unsatisfactory by dentists, but the patients declined offers to remake crowns. Peretz and 1998 RCT; pretreatment Cross-sectional 98 patients DAS scoring indicated that gender and educational level Moshonov190 anxiety influenced anxiety, but that RCT experience and pain did not. Stabholz and 1999 RCT, crown, extraction, Cross-sectional 180 patients DAS scoring indicated that gender influenced anxiety, but Peretz191 comparison that procedure type did not. Chang 1999 ISC; comparison with Cross-sectional 20 patients Patients reported extremely high level of satisfaction with et al192 natural teeth 21 implants appearance using visual analogue scale. Chang 1999 ISC; esthetic outcomes Longitudinal 29 patients Patients reported extremely high level of satisfaction with et al193 5-89 months 41 implants appearance using isual analogue scale, but clinician's satisfaction was lower. Moberg 1999 ISC; evaluation, patient Longitudinal 29 patients 28 patients with surviving implants generally had extremely et al90 satisfaction 1 year 30 implants positive responses to satisfaction, hygiene, biting, speech, esthetics, orofacial pain, and willingness to undergo treatment again. Wannfors and 1999 ISC; outcomes Longitudinal 65 subjects Patients reported extremely high levels of satisfaction Smedberg91 3 years 76 implants comfort, phonetics, and esthetics at baseline and 3-year follow up using a visual analogue scale; somewhat inconsistent with very high prosthetic complication rates. Johnson and 2000 ISC; outcomes Prospective 59 subjects Extremely high levels of patient satisfaction were reported Persson92 3 years 78 implants over time; low levels of altered satisfaction were initially reported, but this largely resolved over time. Gibbard and 2002 ISC; evaluation, Prospective 24 subjects Patients were extremely satisfied with appearance, Zarb78 patient satisfaction 5 years 30 implants function, and willingness to recommend treatment to others, but somewhat less satisfied with cleansability and willingness to undergo treatment again as reported on a Likert scale. Dugas 2002 RCT; life quality Cross-sectional 119 subjects RCT had profoundly positive impact on quality of life, et al194 and satisfaction 238 teeth especially on pain and psychologic state; high degrees of satisfaction were found, cost caused the most dissatis- faction; more satisfaction was found with endodontists.

The Journal of Prosthetic Dentistry Torabinejad et al October 2007 297

Table V. continued (2 of 2) Evidence table for psychosocial effects of implant-supported single crowns, fixed partial denture, and root canal therapies Authors Year Field of Study Study Type Sample Relevant Findings

Watkins 2002 RCT; pain and Cross-sectional 333 patients Pain and unpleasantness experienced during RCT was less et al195 unpleasantness than anticipated. Age and gender differences were found. Sonoyama 2002 ISC and FPD; life quality Cross-sectional 44 responses Quality of life scores were high and did not differ between et al196 comparison implant and resin-bonded FPD treatments with respect to: mastication and oral pain, speech, swallowing, hygiene, esthetics, general physical function and psychological state. Andersson 2003 ISC; evaluation, Retrospective 34 subjects Patients reported high satisfaction levels for postsurgery et al97 patient satisfaction 2-5 years 42 implants information, care, mastication, pronunciation, with lower levels for pretreatment information and pain. Patients and professionals reported high esthetic satisfaction. Vermylen 2003 ISC; patient satisfaction Retrospective 48 patients Patients were positive about esthetics, phonetics, et al197 and quality 3-89 months 52 implants eating, and overall satisfaction; less so about hygiene and cost; more would recommend treatment to others than would have it again. Dentists rated ~1/4 of same crowns as unacceptable. Schropp 2004 ISC; patient experience Prospective 41 subjects Patients were very/extremely satisfied about treatment, et al198 16-18 months 41 implants surgeries, crown making, adaptation, esthetics, chewing; some differences between early and delayed treatments were found; visual analog and categorical questionnaires were used. Levin et al86 2005 ISC; outcomes, esthetics Longitudinal 48 subjects Extremely high rates of surgical survival and success were 1-9 years 52 implants not predictive of esthetic success, which was somewhat lower, mostly due to free gingival margin problems. Pjetursson 2005 ISC; patient satisfaction Prospective 104 patients Patients were highly satisfied with appearance, masticatory et al114 5-15 years 214 implants comfort, speech, esthetics hygiene, cost, fulfillment of expectations, and willingness to repeat treatment and recommend treatment to others; visual analogue scale was used. Udoye 2005 RCT; anxiety; RCT and Cross-sectional 40 patients RCT, followed by extraction, recorded the highest DAS et al199 199 extraction comparison scores. DAS was influenced by age but not by gender. Bragger 2005 ISC and FPD; economic Retrospective 89 patients Implant treatment required more visits, but total treatment et al200 comparison 100 restora- time was similar, and total cost (including laboratory, tions opportunity, and complication costs) was lower than for FPD treatment. Szentpetery 2005 FPD; patient reported 1-12 months 39 FPDs Patients reported high incidence of wide variety of et al201 problems preoperative problems, but these resolved within 1 month of treatment, except for small proportion of food catching and smiling problems.

RCT studies had independent evalu- for FPD studies; and 10 (2) for RCT The total number of participants was ators for 77% and 88% of the papers, studies. Thus, the available literature only reported in 87% of ISC studies, respectively. Study durations varied, lacked many of the attributes desired in 71% of FPD studies, and in 97% of but most studies were of less than for outcomes studies. RCT studies. 6 years’ duration (Tables I-III). The Sample size varied enormously Clinical setting and provider type mean quality rating scores (and as- from 28 to 1,462,936 (Tables I-III). varied among treatment modes. Stud- sociated standard deviations), out of Of the 24 RCT studies reviewed, 2 re- ies were coded as being conducted a possible total of 17 were: 7 (2) for ported large sample sizes of 44,613 in teaching hospitals/dental schools papers describing ISC studies; 7 (3) and 1.45 million subjects (Table III). (30%, 71%, 58%); private practice Torabinejad et al 298 Volume 98 Issue 4 (19%, 16%, 29%); or other/unknown inherently limited. ures 6 through 10. Because 6+-year (49%, 10%, 12%) for ISC, FPD, and Methods of assessment were ra- FPD survival was only represented RCT studies, respectively. A large ma- diographic, clinical, and question- by a single paper, a Forest plot was jority of the studies (72% of ISC stud- naire, or combinations of these. Root not made for this datum. A majority ies; 81% of FPD studies; 79% of RCT canal treatment studies reported the of the ISC papers provided survival studies) reported results from a single most comprehensive outcome assess- rates. In contrast, a majority of the center. Studies were coded as describ- ment, with 88% reporting the use of RCT studies and almost all of the ing care provided by general practi- combined radiographic, clinical, and FPD studies provided success rates. In tioners and dental students (0%, 29%, questionnaire evaluation. Most ISC most cases, pooled and weighted suc- and 63%); specialists (87%, 35%, and studies, 77%, reported a combination cess and survival rates substantially 29%); and unstated (13%, 29%, and of radiographic and clinical evalu- overlapped. However, 1 of the 4 RCT 8%) for ISC, FPD, and RCT studies, ation. Fixed partial denture studies 6+-year studies had a sample size of respectively. reported the most varied methods of 1.45 million subjects (Table III) (Fig. Patient demographics were in- evaluation, with the most common 10). The pooled survival rate of these completely described. Only 65% of being clinical, 35%; followed by radio- 4 studies was 92%, whereas their the included studies noted patient graphic and clinical, 29%. weighted average survival was 97%. gender. Within these studies, subjects Pertinently, pooled and weighted ISC were fairly evenly distributed between Clinical outcomes survival means were both 97% for the men and women, but women formed same 6+-year time period (Table I) a small majority in all treatment Clinical and/or biological out- (Fig. 9). Substantial differences were modalities. Subject age was less fre- comes in the evidence tables are ex- also discerned between the pooled quently described, being reported in pressed in the form of success and and weighted 4- to 6-year FPD suc- only 22% of the ISC studies, 16% of survival rates because data on harm- cess studies (Table II). Paradoxically, the FPD studies, and 32% of the RCT ful effects, beneficial effects, compli- early ISC success rates were computed studies. The socioeconomic status of cations, and other biological effects as being slightly higher than early ISC the participants was indicated in 21% were largely absent or inconsistently survival rates. Such differences reflect of the RCT papers, but not in any ISC reported. Pooled and weighted suc- the methodological limitations of sys- or FPD papers. cess and survival rates for each fol- tematic reviews of heterogeneous lit- Outcome measures were most of- low-up period, with their associated erature. ten crude and cumulative estimates 95% confidence intervals, are listed in of success or failure and of survival Tables I to III. The Forest plots reflect- Extraction without replacement or loss. Success was defined in many ed the heterogeneity of the reviewed different ways both within and among papers. Forest plots for 6+-year suc- The impact of tooth extraction treatment modes; thus, its value was cess and survival are displayed in Fig- without replacement was primar-

Fugazzotto 0.95 (0.94, 0.96)

Levin 0.93 (0.82, 0.98)

Combined 0.95 (0.93, 0.96)

0.800.85 0.90 0.95 1.00 Proportion Successful 6 Forest plot of implant success at 6+ years; proportion meta-analysis plot, random effects model, with 95% confidence intervals in parentheses.

The Journal of Prosthetic Dentistry Torabinejad et al October 2007 299

Karlsson 0.93 (0.89, 0.96)

Valderhaug 0.76 (0.67, 0.84) Priest 0.61 (0.49, 0.72)

Keschbaum 0.80 (0.78, 0.82) Samama 0.83 (0.76, 0.89)

Libby 0.85 (0.76, 0.92)

Probster 0.60 (0.54, 0.65)

Behr 0.62 (0.53, 0.71)

Shugars 0.94 (0.89, 0.98)

Hochman 0.88 (0.75, 0.95) Holm 0.84 (0.75, 0.91)

Olsson 0.83 (0.68, 0.93)

Walton 0.92 (0.89, 0.94)

De Backer 0.73 (0.65, 0.80)

Combined 0.81 (0.74, 0.86) 0.40.6 0.8 1.0 1.2 Proportion Successful 7 Forest plot of fixed partial denture success at 6+ years; proportion meta-analysis plot, random effects model, with 95% confidence intervals in parentheses.

Stoll 0.85 (0.82, 0.88)

Doyle 0.82 (0.76, 0.87)

Combined 0.84 (0.82, 0.87)

0.76 0.80 0.84 0.88 Proportion Successful 8 Forest plot of endodontic success at 6+ years; proportion meta-analysis plot, random ef- fects model, with 95% confidence intervals in parentheses.

Torabinejad et al 300 Volume 98 Issue 4

Scholander 0.98 (0.96, 0.99)

Bianco 0.96 (0.93, 0.98)

Bianchi 1.00 (0.97, 1.00)

Doring 0.98 (0.96, 0.99)

Vigolo 0.95 (0.91, 0.98)

Pjetursson 0.93 (0.89, 0.96)

Combined 0.97 (0.95, 0.99)

0.880.91 0.94 0.97 1.00 Proportion Successful 9 Forest plot of implant survival at 6+ years; proportion meta-analysis plot, random effects model, with 95% confidence intervals in parentheses.

Aquilino 0.89 (0.82, 0.94)

Dammaschke 0.85 (0.79, 0.90)

Salehrabi 0.97 (0.97, 0.97)

Doyle 0.94 (0.90, 0.97)

Combined 0.92 (0.84, 0.97)

0.790.84 0.89 0.94 0.99 Proportion Successful 10 Forest plot of endodontic survival at 6+ years; proportion meta-analysis plot, random effects model, with 95% confidence intervals in parentheses.

ily described by the effects of short- single posterior tooth, creating an Psychosocial outcomes ened and interrupted dental arches interrupted dental arch or bounded and the impact of extraction on life posterior space, had remarkably little Psychosocial or quality of life ef- quality (Table IV). This data was not effect on shifting, decrease in alveo- fects of treatment tended to be report- systematically reviewable and neces- lar support, or loss of adjacent teeth. ed in different ways among treatment sitated narrative review. Moderately Interestingly, provision of an FPD was disciplines. Direct comparison be- shortened dental arches had little, associated with a modestly improved tween different treatment modes was if any, impact on occlusal stability, survival rate of adjacent teeth; how- extremely rare. Masticatory perfor- tooth loading, temporomandibular ever, a causal relationship was not mance and esthetics were commonly disorders, interdental spacing, peri- established. Loss of visible teeth had reported in the implant literature. odontal disease, patient comfort, or momentous psychosocial impact. Fixed partial denture patient-based masticatory performance. Loss of a outcomes were rarely reported, but The Journal of Prosthetic Dentistry Torabinejad et al October 2007 301 a broad range of parameters and pa- operative pain were generally assigned better when endodontic treatment tient complaints were listed. Pretreat- to failure categories. Clinical RCT out- was provided by specialists, in situa- ment anxiety and residual posttreat- comes instruments often included the tions with more severe initial disease, ment pain were commonly addressed objective measurement of pain upon and when the patients had completed in the RCT literature. palpation and percussion, as well as a high school education. A scant amount of FPD literature the patient’s subjective historical ac- Limited psychosocial data suggest- indicated that most patient com- count of the presence or absence of ed that in patients with periodontally plaints centered upon hygiene and pain during masticating or incising, sound teeth that have pulpal and/or functional problems such as food but incorporated these findings into periradicular pathosis, tooth reten- entrapment, sore jaws, and difficulty overall tooth ratings. Overwhelming tion through root canal therapy and eating, but also included avoidance reduction in pain followed RCT care. restoration or tooth replacement with of going out in public and smiling. Comfort levels were extremely high, an implant-supported single crown or However, complaints were resolved at largely equivalent to those following a fixed partial denture resulted in su- follow-up visits. A rare direct compar- ISC treatments. A small minority of perior quality of life outcomes com- ison between ISC and resin-bonded patients reported lingering problems pared to extraction without replace- FPD treatment studied 7 parameters after RCT, the majority of which were ment. (mastication and oral pain, pronun- pain-related. Esthetic outcomes were ciation, swallowing, oral cleansability, often examined in the ISC literature. Economic outcomes esthetics, physical function, and psy- Very high levels of patient satisfaction chological state) and found no differ- were reported in the implant litera- Economic outcome data address- ence between those treatments (Table ture. Although dentist levels of satis- ing the purpose of this study was V).10 faction were high, they were consis- largely absent. Some quality of life Studies of pretreatment anxiety of tently lower than patient ratings. studies indicated that cost was a bar- patients seeking nonsurgical RCT care Patient perceptions of ISC com- rier to RCT; however, the vast major- were somewhat inconsistent; com- plications were rarely reported, but ity of patients believed that both RCT parisons were most commonly made the vast majority of patients believed and ISC costs were justified or that for patients seeking extraction. How- that the number of complications was the cost-benefit was positive (Table ever, patients presenting to the dental acceptable, even when high frequen- V).39,40,114,197 A short-term study com- office for extraction are often already cies of complications were recorded. paring economic aspects of single in pain, as are those presenting for Root canal treatment studies did not tooth replacement by ISCs and FPDs endodontic care. It was suggested separately address complications. in Switzerland found that implant pa- that this may have raised the anxiety However, most RCT outcomes instru- tients required more office visits, but levels for both these patient popula- ments measured patient, clinical, and total time spent by the dentist was tions. Women tended to demonstrate radiographic consequences of com- similar, and that the duration of the more pretreatment anxiety than men, plications and assigned overall tooth treatment, from beginning to end, but this difference decreased with pa- ratings accordingly. was longer for the ISC patients (Table tient age. Pain during RCT was usually Willingness to either undergo the V).11 However, the ISC demonstrated less than anticipated and did not dif- treatment again or to recommend it a superior cost-effectiveness ratio; fer by gender. to others may be a valid indicator of the higher FPD lab fees outweighed Pain associated with treatment has patient satisfaction. High percentag- the implant component costs. Time been analyzed to some degree in the es of ISC and RCT patients reported to function was shorter for RCT than ISC literature, but not to the same ex- willingness to choose the same treat- ISC patients (Table V).12 tent as in the endodontic literature. A ment again. majority of patients reported implant Overall subject satisfaction rat- DISCUSSION treatment not to be painful. Those ings for both implant and endodon- who experienced pain or unpleasant- tic treatments were extremely high, Key findings and their limitations ness rated it as being mild to moder- generally above the 90th percentile. ate. Comfort during mastication was Interestingly, endodontic patients The goal of this systematic review almost universal following implant with postoperative symptoms still re- was to answer 3 clinical questions re- restoration. The vast majority of RCT ported equally high levels of overall garding initial nonsurgical endodon- patients presented with preexisting satisfaction. It was conjectured that tic care compared to extraction and pain; additionally, most also exhibit- this may be due to dramatic diminu- placement of implant, fixed partial ed pain upon preoperative percussion tion of pain levels as well as to an un- denture, or extraction without tooth testing. In the RCT literature, as rep- derstanding of the expected course of replacement. These questions are im- resented in Table III, teeth with post- healing. Satisfaction was significantly portant for the stakeholders in the Torabinejad et al 302 Volume 98 Issue 4 dental health care system (patients, (factoring in sample sizes) success surface implants were excluded and purchasers, brokers, unions, third- rates consistently were higher for im- studies on threaded implants using party payers, and dentists) who may plant therapy than for endodontic the Albrektsson et al criteria and its have differing perspectives and ex- treatment, which in turn were better derivatives dominated.41 Only studies pectations. Although the methods than for fixed partial denture treat- that reported RCT results in terms of allowed for the broadest capture ment. Additionally, root canal, im- teeth, not roots, were included. Hence, of the literature related to the ques- plant-supported single crown, and many otherwise useful studies were tions, some articles may still have fixed partial denture treatments had excluded. Reporting RCT outcomes been missed, particularly those ap- superior psychosocial outcomes, pri- in terms of individual roots may have pearing in another language that marily with respect to patient self-im- had more relevance in the past when were not subsequently reprinted in age, compared to extraction without apical surgery of the affected root was English. Consideration for inclusion replacement. the predominant treatment for failed of articles independently and then in RCT. However, the currently accepted group discussion helped to avoid the Clinical outcomes, literature quality, modality is nonsurgical retreatment bias of single reviewer decisions. Par- and bias of the entire tooth. In any case, from a ticipation of experienced statisticians patient’s perspective, a single painful helped to ensure proper article clas- The mean quality rating scores, root indicates treatment failure for a sification and appropriate data place- out of a possible total of 17, were: tooth. Other biases and confounding ment in the table of evidence. 7 for papers describing ISC and FPD effects may have manifested. The evidence identified by the studies, and 10 for RCT studies. authors did not permit them to de- Thus, the literature generally lacked Clinical outcomes, success or survival finitively answer all of the questions the methodological quality com- posed. The studies demonstrated monly accepted as being indicative of Success criteria used in implant substantial variability in composition the best practices in study design and studies varied.14 The most frequently (study design, sample size, clinical set- conduct.33 used criteria were those developed by ting and provider type, patient demo- The implant discipline produced Albrektsson et al,41 and a simple mea- graphics), types of treatment proce- the highest number of usable papers surement of periimplant annual mar- dures, and evaluation criteria among in the shortest time (46 papers in 13 ginal bone loss. Closely related criteria and within disciplines. Also, virtually years), followed by fixed partial den- were also often used.42-45 The original no direct comparisons of one treat- tures (31 papers in 22 years), and by Albrektsson criteria included absence ment with another have been report- root canal treatments (24 papers in of mobility, absence of periimplant ed. Hence, the evidence available for 27 years). This may reflect historical radiolucency, absence of signs and answering the questions came from differences among the maturities of symptoms, low rates of vertical bone indirect comparisons, that is, com- these disciplines. However, the older loss, and high 5- and 10-year success paring the reported success and sur- endodontic literature recorded the rates; minor modifications of these vival rates from 1 group of studies for highest overall quality rating and in- criteria are often made. The Albrekts- 1 type of treatment with those from cluded the most high-level studies. son criteria were developed at a time another group of studies for another Changes in treatments that have oc- when it was important to distinguish type of treatment. For this reason, curred over time may have introduced the biological outcomes of osseoin- the conclusions must remain tenta- biases favoring the discipline with tegrated implants from those of their tive, and there is a clear need for addi- the most recent papers. Conversely, predecessors; thus, restorative and tional studies that ideally randomize the discipline currently undergo- patient-based parameters received assignment to alternative treatments, ing the most rapid evolution may be less attention. Later criteria added or at least conduct comparison of the disfavored, because recent changes esthetic parameters.42 Criteria de- treatments using standardized meth- may take some years before being veloped by Buser46 were infrequently ods and measures. reflected in the outcomes literature. used. Some studies used probing Given these critical qualifications, The type of clinical provider created depth and bleeding on probing, the data demonstrated that in pa- a bias. Implant treatment was largely whereas others have not.47 Although tients with periodontally sound teeth provided by specialists; whereas, RCT the absence of pathology or inflam- that have pulpal and/or periradicular was largely provided by generalists or mation is common to most success pathosis, implant and root canal treat- students. criteria, studies did not include the ments had superior 6+-year weighted The inclusion criteria may have led specific parameters historically re- survival compared to replacement us- to unintended selection biases. For ported in the periodontal literature. ing fixed partial dentures. It also ap- example, only threaded implants were Evaluation of these parameters may pears that both pooled and weighted included. Thus, macro-scale smooth become more widespread within the The Journal of Prosthetic Dentistry Torabinejad et al October 2007 303 implant literature. Interestingly, the RCT studies, which often combine Few papers were identified that year of publication appeared unre- comprehensive clinical, radiographic, directly compared the outcome or lated to the choice of success criteria. and anamnestic patient symptom benefits or harmful effects of initial The measurement of annual margin- components.51 Endodontic outcomes nonsurgical RCT and those of extrac- al bone loss was a common thread measures were originally designed to tion and placement of ISCs, FPDs, among the included literature. It has enable the correlation of small dif- or extraction without tooth replace- been suggested that implant success ferences in healing with prognostic ment. These difficulties paralleled criteria are not routinely applied in indicators, not to describe patient-re- those of recent systematic reviews by much of the implant outcomes litera- lated clinical performance.51,52 Unlike Salinas and Eckert14 and by Iqbal and ture.14 Carr48 has argued that future ISC and FPD therapies, RCT aims to Kim.15 Lack of comparative studies implant success criteria must include cure existing disease. Thus, RCT stud- with similar criteria for assessment of multiple outcome domains, including ies measure both the healing of exist- the outcomes, beneficial and harmful consideration of the prosthesis, so ing disease and the occurrence of new effects, with comparable time inter- that measured implant outcomes will disease.53 Hence, many RCT studies vals made it difficult to make realistic have tangible meaning for patients. report data in terms of multiple cat- comparison among these treatment Success and even survival criteria egories of outcomes spanning the modalities. have not always been clearly defined healing process, in contrast to most Direct comparison was extremely in FPD studies (Table II).49 Terms such ISC and FPD data, which is reported rare; only 1 paper directly compared as clinical retention rate and life span in terms of binary success or failure implant and RCT clinical outcomes.12 have been used instead of survival; categories. Endodontic healing often That paper had a retrospective case the methods for calculating these out- takes several years to occur, which control design; that is, without ran- comes have not always been reported may account for the higher RCT suc- dom assignment. Most implants had clearly. Success has been described cess rates with medium-term follow- been placed and restored by special- as complete survival or as functional up times reported in Table III. ists or specialty residents, whereas survival. Failures have been designat- Due to these considerable differ- dental students, residents, or staff ed as being biologic, technical, or pa- ences in meanings of success among clinicians performed most RCTs. In tient-related; as being necessitated by and within disciplines, it is probable this rare instance, follow-up time was remedial treatment or by a remake; as that consideration of survival rates, started at restoration, not at implant having reversible or irreversible com- with and without minor and major placement; however, the authors did plications; and as being primary or interventions, will permit less biased, record complications that occurred secondary. In an effort to allow com- albeit less informative, compari- before restoration. Interestingly, im- parison with previous research, some sons.12,54-56 plant-supported crowns that neces- authors have used prior classification Long-term 6+-year weighted sur- sitated further interventions due to systems. However, the CDA/USPHS vival data indicated that in patients the occurrence of complications or classification system was rarely used.50 with periodontally sound teeth hav- restorative problems were assigned Most authors documented complica- ing pulpal and/or periradicular pa- to unsuccessful categories. Thus, the tions such as caries, need for endodon- thosis, root canal therapy resulted in authors reported much lower success tic treatment, and loss of retention, superior survival (97%) to extraction rates than generally described in the esthetics, periodontal disease, tooth and replacement of the missing tooth implant literature. The authors did fracture, prosthesis fracture, and por- with a fixed partial denture (82%), not specify the types of implant and celain veneer fracture. Resin-bonded and resulted in equal outcomes to endodontic treatments used within FPDs were included due to the broad extraction and replacement of the the study; but later personally com- volume of available data and the vi- missing tooth with an implant (97%) municated that most implants were of ability of the treatment modality, par- (Tables I to III). In contrast, 6+-year the screw-vent type and that all end- ticularly in the replacement of missing success data ranked implant therapy odontic treatments used conventional anterior teeth. Prosthesis debonding (95%) as being superior to endodon- methods including lateral and vertical was a commonly described complica- tic treatment (84%), which in turn condensation (Walter Bowles, DDS, tion of resin-bonded prostheses. In- was ranked as being superior to fixed April 13, 2007, written personal com- terestingly, there appeared to be little prosthodontic treatment (80%) (Ta- munication). Because of lack of de- difference in complication rates of bles I to III). However, differing mean- tailed information regarding the type resin-bonded and conventional fixed ings of success limit the value of these of implants used in this retrospective prostheses in this review. observations. study, this paper was excluded from Success, failure, and their inter- the implant evidence table. The au- mediate stages have been described Clinical outcomes, direct compari- thors concluded that restored end- by many outcomes instruments in sons odontically treated teeth and single Torabinejad et al 304 Volume 98 Issue 4 implant-supported restorations had After the cut-off date for inclu- spective data on large sample sizes is similar survival rates; however, the sion in this systematic review, another needed. implant group showed longer time large endodontic survival study was to function and a substantially higher published.64 That study reported a 5- Clinical outcomes, complications incidence of postoperative complica- year endodontic survival rate of 93% tions requiring subsequent treatment for a sample of 1.56 million teeth in a Treatment complications were intervention. Other rare comparisons Taiwanese population. Had this study dealt with differently among the treat- found that ISCs and FPDs did not dif- been included in the current analy- ment modes adddressed within this fer in their psychosocial impact, and sis, both pooled and weighted 4- to study. In the implant studies, evalu- that ISCs had a superior cost-effec- 6-year survival rates would have been ation of complications other than tiveness ratio to FPDs.10,11 decreased slightly, but not below the implant loss was generally limited.41 A recent systematic review compar- 95% confidence limits reported in Several of the fixed prosthodontic ing the clinical outcomes of restored Table III. studies provided data on common endodontically treated teeth with The superior long-term survival complications (Table II). In contrast, those of implant-supported restora- rates of endodontic therapy suggest most endodontic studies assigned tions concluded that survival rates of that this treatment should be given teeth with clinical, radiographic, or restored endodontically treated teeth priority in treatment planning for patient-related signs or symptoms of and single implants did not differ, and periodontally sound single teeth with complications to failure categories that the decision to treat a tooth end- pulpal and or periradicular pathology (Table III). Other reviews have report- odontically or replace it with an im- (Tables I to III) (Figs. 9 and 10). The ed high incidences of implant com- plant must be based on factors other superior long-term survival rates of plications.55,65 One of these reviews than the treatment outcomes of the single tooth implants suggest that this adopted a narrative approach due to procedures themselves.15 As in the treatment should be given priority in the inherent limitations of the litera- current study, the authors reported treatment planning for teeth that are ture65; the other applied a systematic slightly higher, but not statistically planned for extraction. However, the approach, but only 4 studies could be significantly so, long-term (6-year) many shortcomings of the available included.55 Complication rates may survival rates for implants. Unlike literature limit the strength of such a have been overestimated in these re- this analysis, the authors included sweeping recommendation. Further- views.66 Additionally, recent advances only endodontically treated teeth that more, treatment plans must be based may have subsequently reduced the were subsequently restored. upon the individual patient’s situa- incidence of complications; for exam- Another recent systematic review tion. ple, increased use of cemented abut- compared the clinical outcomes of Clearly, more data, especially from ments and torque devices may have tooth-supported restorations with prospective controlled clinical tri- already decreased the incidence of those of implant-supported restora- als, is needed to answer to questions screw loosening. However, several of tions.14 Consistent with this study, the such as: “Under what circumstances the studies listed in Table V described authors concluded that at 60 months, should a tooth be retained through extreme ISC complication rates; 1 ISCs had a higher survival rate than RCT and restoration, or should it be reported a 3-year complication rate those supported by FPDs; however, extracted and replaced by an implant- of 92%.67 Likewise, high rates of FPD if resin-bonded FPDs were excluded, supported crown or by a fixed partial complications have been reported.68 no difference was found. Unlike this denture?” In a recent publication, It appeared that complications rarely study, resin-bonded FPDs had a sig- Doyle et al13 retrospectively examined necessitated loss of an implant, loss nificantly lower success rate than con- factors affecting outcomes for single- of an FPD, or loss of an endodonti- ventional FPDs. However, different tooth implants and endodontically cally treated tooth, but frequently studies were included and a different treated teeth restorations. The au- required additional intervention. As- time period was reported. The au- thors reported that both therapies are signment of complications to cat- thors reported that FPD success rates affected by smoking, but not by dia- egories requiring major and minor continued to drop steadily over time betes, age, or gender. RCT outcomes interventions would be a reasonable beyond 60 months. were affected by the presence of peri- way to uniformly address different Insofar as comparisons can be radicular periodontitis, post and core types of complications among differ- made, the results of this broad system- placement, and overfilling, but not by ent disciplines in a clinically relevant atic review were in general agreement the number of appointments. Within manner.12 Different temporal failure with other prior, more narrowly fo- limits, implant outcomes were not af- and complication patterns may affect cused systematic reviews on implant, fected by implant length, diameter, or different treatment modes in different fixed partial denture, and endodontic the presence of an adjacent endodon- ways.6,12,14,65,68 For example, early loss success and survival rates.49,55,57-63 tically treated tooth. Long-term pro- rates of osseointegrated implants may The Journal of Prosthetic Dentistry Torabinejad et al October 2007 305 be considerably higher than later loss tinguished from overall survival and Benefits and harms may take decades rates. Conversely, retained teeth may success data (Tables I-III). Some ben- to manifest, but most of the studies be more susceptible to late failure efit and harm data was described in this systematic review were of 6 or due to the effects of coronal leakage within the single tooth extraction fewer years in duration. or microbial ingress, caries, and peri- without replacement and psychoso- odontal disease. cial results sections (Tables IV and V). Economic outcomes Other benefits and harms were not Psychosocial outcomes directly captured by this systematic Only minimal economic data was review, but are largely self-evident. identified within this systematic re- Limited psychosocial data was The principal benefits of extrac- view. Evidence-based studies of com- identified in this systematic review tion are pain relief and removal of dis- parative survival rates should include (Tables IV and V); this was summa- eased tissues. The principal harmful an economic assessment of outcomes. rized within the previously mentioned effect of single tooth extraction with- Economic outcomes are generally de- results. However, psychosocial or life out replacement is its tremendous scribed by cost-effectiveness (C/E) quality effects are likely critical to pa- impact on patient’s perceptions of and cost-benefit (B/C) ratio analyses. tients. Esthetic and comfort-related themselves (Table IV). Physiological These techniques have been applied questions might be particularly im- effects appear to be relatively minor in health care both to evaluate com- portant. The study of the psychoso- (Table IV), but surgical complications peting programs, such as prevention cial effects of single tooth loss, reten- and sequellae may be encountered. of disease versus its treatment, and tion, or replacement is in its infancy. Benefits of retaining a tooth by to evaluate competing therapies for Although few psychosocial studies treatment of pulpal and/or perira- similar health conditions, such as the were identified, strong trends were dicular pathosis and restoration may treatment of coronary artery disease evident. include conservation of the remaining as a sequela of atherosclerosis.18-22 Limited psychosocial data sug- crown and root structure, preserva- Different perspectives can be used to gested that tooth retention through tion of alveolar bone and accompany- conduct C/E and C/B analyses; stud- root canal therapy and restoration or ing papillae, preservation of pressure ies can be approached from the point tooth replacement with an implant or perception, and lack of movement of of view of the providers or from the a fixed partial denture results in supe- the surrounding teeth. Conversely, a point of view of the consumers. The rior clinical outcomes, compared to retained tooth may be at risk for fu- most general approach is from the extraction without replacement. The ture root fracture and development of perspective of society as a whole. reasons for this were due to diminu- caries or periodontal disease. With this approach, the total benefits tion of esthetics and psychological The primary benefits of replace- and total costs from all sources and trauma associated with tooth loss, ment of a missing tooth with a fixed all participants are counted in the such as self-image, not physiological partial denture may be patient self- evaluation of alternative therapies. function. image and esthetics, with minor Cost-effectiveness is the simpler physiologic gains (Tables IV and V). approach because it holds the out- Biological outcomes Tooth preparation and subsequent come constant. For a given outcome, provision of fixed partial dentures are for instance, removal of disease and Remarkably little data focusing widely considered to increase the fu- restoration of maximum attainable upon biological outcomes, and their ture risk of pulpal, periradicular, and function to the dentition, costs of al- benefits or harmful effects, such as periodontal diseases. Likewise, the ternatives are compared. As long as inflammation, infection, and caries primary benefits of replacement of the outcome (benefit) is the same for activity, were identified. However, a missing tooth with a fixed partial all alternative therapies, the approach measures of their surrogates, such denture may be self-image and es- is essentially a cost comparison; the as radiographic signs of bone loss, thetics, with minor physiologic gains least-cost alternative being preferred. or pain on masticating, were often (Tables IV and V). Unlike fixed partial This C/E approach estimates the rela- included within clinical outcomes in- denture treatment, implant treatment tive efficiency of the alternatives. The struments. Biological outcomes, ben- does not involve preparation and res- therapy that requires fewer resources efits, and harmful effects have been toration of adjacent teeth and the as measured by clinician time and noted within the literature, but less attendant risks. Implant placement training, and cost of materials, is frequently measured or compared. may help to prevent bone resorption more efficient in conserving resourc- after extraction. All means of tooth es. Economic costs may be borne by Benefits and harms replacement may face esthetic chal- patients, dentists, third parties, or by lenges in recreating natural hard and society. Benefits and harms were rarely dis- soft tissue contour and appearance. Initial costs, in US dollars, of each Torabinejad et al 306 Volume 98 Issue 4 of the 4 treatment alternatives can be restorations. Clearly, initial costs were has not emerged regarding C/B of the calculated using the national fee aver- lowest for the extraction-only option. alternative services within the dental ages collected by the American Den- Among the remaining 3 options, RCT profession. This systematic review of tal Association through its Services is the lowest. The cost ranges of the the existing literature demonstrated Rendered Survey to yield national ISC and FPD therapies overlapped. that studies specifically designed to and subnational estimates of fees However, these are just initial costs, assess the cost-benefit of the 4 alter- for general practitioners (GPs) and not lifetime costs, and as for all com- native services are almost completely specialists for each CDT4 code (The parisons made within this review, a absent. American Dental Association’s Code sound periodontium was assumed. Nevertheless, the parameters for on Dental Procedures and Nomencla- The assumption of comparable an evidence-based C/B comparison ture). Although this survey contains outcomes with C/E analysis is an in- of these alternatives are well under- proprietary information, and lacks herent shortcoming. Of the 4 thera- stood. Since root canal therapy re- of journal review board peer-review, pies being compared in this review, 3 tains a natural tooth, most will recog- these factors do not negate its value options result in the loss of a natural nize this as a benefit that the other 3 with respect to systematic review of tooth. Only 1 alternative preserves therapies do not provide. Of course, the best available evidence. These data the natural tooth and its sound peri- the natural tooth must not have resid- have been used to illustrate the con- odontium. Since the outcomes are not ual pathology of clinical significance, duct of a simple cost-benefit analysis identical, B/E is the appropriate ap- must fulfill its function within the den- below. These fees were only the initial proach to comparison of alternative tition, not be a source of discomfort costs of the therapies at the time this therapies. However, this approach en- for the patient, and have acceptable paper went to press; whereas, lifetime tails more than simply comparing to- esthetics. If these requirements are costs are more meaningful. The initial tal costs and choosing the service that met by retention, then choice of an- costs of a simple extraction, provided costs the least. Instead, benefit, or val- other alternative on a C/B basis must by a general practitioner or an oral ue to the patient, must be defined and provide greater functionality, less dis- surgeon, are $101 and $123, respec- measured. Relative treatment longev- comfort, or better esthetics than root tively. The initial cost of an extraction, ity is an important dimension of C/B canal therapy. Again, one can again endosteal implant, abutment, and evaluations; lifetime C/B comparisons start with a reasonable assumption: crown is approximately $2850 and are more meaningful than time to the it is better to preserve natural denti- does not vary substantially whether next treatment. Limited evidence sug- tion than to lose natural teeth even if a general dentist, an oral surgeon, or gests that long-term complication replaced by an implant or prosthesis. a periodontist provides the surgical rates differ substantially among the Consequently, the burden of proof care. The initial costs of an extrac- therapeutic choices addressed in this lies with the alternatives to root canal tion followed by a 3-unit FPD using a systematic review and that retention therapy. It needs to be demonstrated high noble metal-ceramic restoration with endodontic therapy may have that 1 of these alternatives results in differs considerably, depending on lower complication rates.12,65,68 less total lifetime costs or provides whether general dentists or prosth- Benefits of health care usually in- greater lifetime function, freedom odontists provide the FPD, and are clude removal of existing pathology, from pathology, comfort, or accept- $2300 and $3300, respectively. The prevention of future or recurrent pa- ability to a patient. Currently, such costs of an anterior RCT provided by thology, restoration of function, ab- data is unavailable. Although eco- a general dentist with a composite sence of discomfort or pain, esthetics, nomic data is largely absent, reten- resin restoration, and a molar RCT and psychological acceptance of the tion of a periodontally sound tooth provided by an endodontist followed services by the patient. If the service clearly has tremendous cost-benefit by an amalgam foundation and a is delivered within a market (volun- and cost-effectiveness in comparison high noble metal-ceramic crown, are tary exchange between the patient to any alternative where the tooth is approximately $743 and $1765, re- and the health professional), and the lost. spectively. These 2 examples of RCT patient is well informed (can evalu- and restoration were chosen so as to ate the various aspects of benefits), CONCLUSIONS bracket the cost range. This simple market prices should provide a fairly analysis does not include consulta- accurate indication and the relative The existing literatures describing tion fees; preoperative radiographs, cost/benefit of the 4 alternatives. outcomes of using root canal thera- which may vary from simple periapi- However, most observers question py, extraction without replacement, cal views to cone-beam tomography whether or not patients can make a extraction with replacement using a and CT; or additional, separately C/B evaluation of such a technical na- fixed partial denture, and extraction charged procedures such as surgical ture regarding individually produced with replacement using an implant, guides or some types of provisional services, especially since a consensus is problematic. Comparative stud- The Journal of Prosthetic Dentistry Torabinejad et al October 2007 307 ies were absent, success was defined dilemma. Implant Dent 2002;11:217-23. analysis--a prerequisite of a rational phar- in very different ways both within 4. Salinas TJ. Three-unit fixed partial dentures macotherapy in cardiovascular diseases. versus single-tooth implant restorations. Timely thrombolysis in the acute myocar- and among the different treatment Pract Proced Aesthet Dent 2003;15:372. dial infarction. Int J Clin Pharmacol Ther modes, complications were largely 5. Salinas TJ, Block MS, Sadan A. Fixed partial 1996;34:277-81. denture or single-tooth implant restora- 22.Hornberger J. A cost-benefit analysis of a undescribed, and psychosocial out- tion? Statistical considerations for sequenc- cardiovascular disease prevention trial, us- comes were incompletely addressed. ing and treatment. J Oral Maxillofac Surg ing folate supplementation as an example. For these reasons, the questions ad- 2004;62(Suppl 2):2-16. Am J Public Health 1998;88:61-7. 6. White SN, Miklus VG, Potter KS, Cho J, 23.Brent RJ. Cost-benefit analysis and health dressed in this review must be an- Ngan AYW. Endodontics and implants, care evaluations. Cheltenham: Edward swered only tentatively, and with ref- a catalog of therapeutic contrasts. J Evid Elgar Publishing; 2004. p. 1-48. erence only to 2 outcomes. Based Dent Pract 2006;6:101-9. 24.Boardman AE, Greenberg DH, Vining AR, 7. Torabinejad M, Goodacre CJ. Endodon- Weimer DL. Cost-benefit analysis: concepts Based on available evidence it ap- tic or dental implant therapy: the factors and practice. 3rd ed. Upper Saddle River: pears that initial endodontic treat- affecting treatment planning. J Am Dent Prentice Hall; 2005. p. 1-56. ment has high long-term survival rate Assoc 2006;137:973-7. 25.Brent RJ. Applied cost-benefit analysis. 2nd 8. Thomas MV, Beagle JR. Evidence-based ed. Cheltenham: Edward Elgar Publishing; for periodontally sound teeth that decision making: implants versus natural 2007. p. 3-28. have pulpal and/or periapical pa- teeth. Dent Clin North Am 2006;50:451- 26.Adler MD, Posner EA. New foundations of thosis. Equivalent long-term survival 61. cost-benefit analysis. Cambridge: Harvard 9. Dawson AS, Cardaci SC. Endodontics ver- University Press; 2007. p. 1-80. rates have been also reported for ex- sus implantology: to extirpate or integrate? 27.Egger M, Smith GD, Altman DG. System- traction and replacement of the miss- Aust Endod J 2006;32:57-63. atic reviews in healthcare: meta analysis in 10.Sonoyama W, Kuboki T, Okamoto S, context. 2nd ed. London: British Medical ing tooth with an implant-supported Suzuki H, Arakawa H, Kanyama M, et al. Association; 2001. p. 3-19. restoration. Substantially lower long- Quality of life assessment in patients with 28.Carr AB. Systematic reviews of the litera- term survival rates have been report- implant-supported and resin-bonded fixed ture: the overview and meta-analysis. Dent prosthesis for bounded edentulous spaces. Clin North Am 2002;46:79-86. ed for extraction and replacement of Clin Oral Implants Res 2002;13:359-64. 29.Bader JD. Systematic reviews and their the missing tooth with fixed partial 11.Bragger U, Krenander P, Lang NP. Eco- implications for dental practice. Tex Dent J dentures. nomic aspects of single-tooth replacement. 2004;121:380-7. Clin Oral Implants Res 2005;16:335-41. 30.Sjogren P, Halling A. Medline search For patients with periodontally 12.Doyle SL, Hodges JS, Pesun IJ, Law AS, validity for randomised controlled trials in sound teeth that have pulpal and/or Bowles WR. Retrospective cross sectional different areas of dental research. Br Dent J periradicular pathosis, implant, end- comparison of initial nonsurgical endodon- 2002;192:97-9. tic treatment and single-tooth implants. J 31.Bradley DR, Rana GK, Martin PW, Schum- odontic, and fixed prosthodontic Endod 2006;32:822-7. acher RE. Real-time, evidence-based medi- treatments had superior psychoso- 13.Doyle SL, Hodges JS, Pesun IJ, Baisden MK, cine instruction: a randomized controlled cial outcomes, primarily with respect Bowles WR. Factors affecting outcomes trial in a neonatal intensive care unit. J Med for single-tooth implants and endodontic Libr Assoc 2002;90:194-201. to patient self-image, compared to restorations. J Endod 2007;33:399-402. 32.Shipley M. Evidence based filters for Ovid extraction without replacement or 14.Salinas TJ, Eckert SE. In patients requir- Medline. Nesbit guide to evidence based with replacement using a fixed par- ing single-tooth replacement, what are resources. Edward G. Miner Library, Uni- the outcomes of implant - as compared to versity of Rochester Medical Center. 2004. tial denture. Prospective large indi- tooth-supported restorations? Int J Oral http://www.urmc.rochester.edu/hslt/min- vidual or multicenter clinical trials Maxillofac Implants 2007;22(Suppl):71-95 er/digital_library/tip_sheets/OVID_eb_fil- 15.Iqbal MK, Kim S. For teeth requiring end- ters.pdf Cited Sept. 4, 2007. with clearly defined clinical criteria for odontic treatment, what are the differences 33.West S, King V, Carey TS, Lohr KN, McKoy survival, with and without interven- in outcomes of restored endodontically N, Sutton SF, et al. Systems to rate the tion; patient life quality information; treated teeth compared to implant-sup- strength of scientific evidence. Evidence ported restorations? Int J Oral Maxillofac report/technology assessment no. 47 and economic outcomes are needed Implants 2007;22(Suppl):96-116 (Prepared by the Research Triangle Institute to compare alternative treatments. 16.Torabinejad M, Bahjri K. Essential elements - University of North Carolina Evidence- High-level studies will require exper- of evidenced-based endodontics: steps based Practice Center, under Contract involved in conducting clinical research. J No. 290-97-0011). AHRQ publication no. tise, time, and economical support Endod 2005;31:563-9. 02-E016. Rockville: Agency for Healthcare from the various stakeholders. 17.Forrest JL, Miller SA. The anatomy of evi- Research and Quality. 2002. dence-based publications: article summa- 34.Juni P, Altman DG, Egger M: Systematic re- ries and systematic reviews. Part I. J Dent views in health care: assessing the quality of REFERENCES Hyg 2004;78:343-8. controlled clinical trials. BMJ 2001;323:42- 18.Flagle CD. Some approaches to cost 6. Citation references benefit analysis and evaluation in cardio- 35.Egger M, Juni P, Bartlett C, Holenstein F, vascular disease. Cardiovasc Res Cent Bull Sterne J. How important are comprehensive 1976;15:29-32. literature searches and the assessment of 1. Meadows LM, Verdi AJ, Crabtree BF. 19.O’Brien B, Rushby J. Outcome assessment trial quality in systematic reviews? Empirical Keeping up appearances: using qualitative in cardiovascular cost-benefit studies. Am study. Health Technol Assess 2003;7:1-76. research to enhance knowledge of dental Heart J 1990;119:740-7. 36.Lau J, Ioannidis JP, Schmid CH. Quantita- practice. J Dent Educ 2003;67:981-90. 20.Berg JE. Screening for cardiovascular risk: tive synthesis in systemic reviews. Ann 2. Lambert H. Accounting for EBM: notions cost-benefit considerations in a comparison Intern Med 1997;127:820-6. of evidence in medicine. Soc Sci Med of total cholesterol measurements and two 37.Higgins JP, Thompson SG. Quantifying 2006;62:2633-45. compound blood lipid indices. J Cardiovasc heterogeneity in a meta-analysis. Stat Med 3. Bader HI. Treatment planning for implants Risk 1995;2:441-447. 2002;21:1539-58. versus root canal therapy: a contemporary 21.Barthel W, Haustein KO. Cost-benefit 38.Newcombe RG. Two-sided confidence Torabinejad et al 308 Volume 98 Issue 4

intervals for the single proportion: 55.Creugers NH, Kreulen CM, Snoek PA, de 71.Polizzi G, Rangert B, Lekholm U, Gualini comparison of seven methods. Stat Med Kanter RJ. A systematic review of single- F, Lindstrom H. Brånemark System Wide 1998;17:857-72. tooth restorations supported by implants. J Platform implants for single molar replace- 39.Lobb WK, Zakariasen KL, McGrath PJ. Dent 2000;28:209-17. ment: clinical evaluation of prospective and Endodontic treatment outcomes: do pa- 56.Eckert SE, Choi YG, Sanchez AR, Koka S. retrospective materials. Clin Implant Dent tients perceive problems? J Am Dent Assoc Comparison of dental implant systems: Relat Res 2000;2:61-9. 1996;127:597-600. quality of clinical evidence and prediction 72.Norton MR. A short-term clinical evalu- 40.Dugas NN, Lawrence HP, Teplitsky P, of 5-year survival. Int J Oral Maxillofac ation of immediately restored maxillary Friedman S. Quality of life and satisfac- Implants 2005;20:406-15. TiOblast single-tooth implants. Int J Oral tion outcomes of endodontic treatment. J 57.Scurria MS, Bader JD, Shugars DA. Meta- Maxillofac Implants 2004;19:274-81. Endod 2002;28:819-27. analysis of fixed partial denture survival: 73.Tsirlis AT. Clinical evaluation of immedi- 41.Albrektsson T, Zarb G, Worthington P, prostheses and abutments. J Prosthet Dent ate loaded upper anterior single implants. Eriksson AR. The long-term efficacy of 1998;79:459-64. Implant Dent 2005;14:94-103. currently used dental implants: a review 58.Basmadjian-Charles CL, Farge P, Bourgeois 74.Zarone F, Sorrentino R, Vaccaro F, Russo and proposed criteria of success. Int J Oral DM, Lebrun T. Factors influencing the S. Prosthetic treatment of maxillary lateral Maxillofac Implants 1986;1:11-25. long-term results of endodontic treat- incisor agenesis with osseointegrated im- 42.Smith DE, Zarb GA. Criteria for success ment: a review of the literature. Int Dent J plants: a 24-39-month prospective clinical of osseointegrated endosseous implants. J 2002;52:81-6. study. Clin Oral Implants Res 2006;17:94- Prosthet Dent 1989;62:567-72. 59.Creugers NH, Kreulen CM. Systematic 101. 43.Albrektsson T, Zarb GA. Current interpre- review of 10 years of systematic reviews 75.Henry PJ, Laney WR, Jemt T, Harris D, tations of the osseointegrated response: in prosthodontics. Int J Prosthodont Krogh PH, Polizzi G, et al. Osseointegrated clinical significance. Int J Prosthodont 2003;16:123-7. implants for single-tooth replacement: a 1993;6:95-105. 60.Kojima K, Inamoto K, Nagamatsu K, Hara prospective 5-year multicenter study. Int J 44.Zarb GA, Albrektsson T. Osseointegration: A, Nakata K, Morita I, et al. Success rate Oral Maxillofac Implants 1996;11:450-5. a requiem for the periodontal ligament? of endodontic treatment of teeth with vital 76.Scheller H, Urgell JP, Kultje C, Klineberg I, (Editorial) Int J Periodontics Restorative and nonvital pulps. A meta-analysis. Oral Goldberg PV, Stevenson-Moore P, et al. A Dent 1991;11:88-91. Surg Oral Med Oral Pathol Oral Radiol 5-year multicenter study on implant-sup- 45.Albrektsson T, Isidor F. Consensus report of Endod 2004;97:95-9. ported single crown restorations. Int J Oral session V. Proceedings of the 1st European 61.Sathorn C, Parashos P, Messer HH. Ef- Maxillofac Implants 1998;13:212-8. workshop on periodontology. In: Lang NP, fectiveness of single- versus multiple-visit 77.Polizzi G, Fabbro S, Furri M, Herrmann I, Karring T. Proceedings of the 1st Euro- endodontic treatment of teeth with apical Squarzoni S. Clinical application of narrow pean workshop on periodontology. Berlin: periodontitis: a systematic review and Brånemark System implants for single- Quintessenz-Verlag. 1994 p. 365-9. meta-analysis. Int Endod J 2005;38:347-55. tooth restorations. Int J Oral Maxillofac 46.Buser D, Weber HP, Lang NP. Tissue inte- 62.Schaeffer MA, White RR, Walton RE. Implants 1999;14:496-503. gration of non-submerged implants. 1-year Determining the obturation length: a meta- 78.Gibbard LL, Zarb G. A 5-year prospec- results of a prospective study with 100 ITI analysis of literature. J Endod 2005;31:271- tive study of implant-supported single- hollow-cylinder and hollow-screw implants. 4. tooth replacements. J Can Dent Assoc Clin Oral Implants Res 1990;1:33-40. 63.Peng L, Ye L, Tan H, Zhou X. Outcome of 2002;68:110-6. 47.Karoussis IK, Bragger U, Salvi GE, Burgin root canal obturation by warm gutta-per- 79.Mayer TM, Hawley CE, Gunsolley JC, Feld- W, Lang NP. Effect of implant design on cha versus cold lateral condensation: a man S. The single-tooth implant: a viable survival and success rates of titanium oral meta-analysis. J Endod 2007;33:106-9. alternative for single-tooth replacement. J implants: a 10-year prospective cohort 64.Chen SC, Cheuh LH, Hsiao CK, Tsai MY, Periodontol 2002;73:687-93. study of the ITI Dental Implant System. Ho SC, Chiang CP. An epidemiologic study 80.Prosper L, Gherlone EF, Redaelli S, Quar- Clin Oral Implants Res 2004;15:8-17. of tooth retention after nonsurgical end- anta M. Four-year follow-up of larger-di- 48.Carr AB. Successful long-term treatment odontic treatment in a large population in ameter implants placed in fresh extraction outcomes in the field of osseointegrated Taiwan. J Endod 2007;33:226-9. sockets using a resorbable membrane or a implants: prosthodontic determinants. Int J 65.Goodacre CJ, Bernal G, Rungcharassaeng resorbable alloplastic material. Int J Oral Prosthodont 1998;11:502-12. K, Kan JY. Clinical complications with Maxillofac Implants 2003;18:856-64. 49.Creugers NH, Kayser AF, van ‘t Hof MA. A implants and implant prostheses. J Prosthet 81.Covani U, Crespi R, Cornelini R, Barone meta-analysis of durability data on conven- Dent 2003;90:121-32. A. Immediate implants supporting single tional fixed bridges. Community Dent Oral 66.Jokstad A. Common complications with crown restoration: a 4-year prospective Epidemiol 1994;22:448-52. implants and implant prostheses. Evid study. J Periodontol 2004;75:982-8. 50.Ryge G, Cvar JF. Criteria for the clinical Based Dent 2004;5:70-1. 82.Nentwig GH. Ankylos implant system: evaluation of dental restorative materials. 67.Wannfors K, Smedberg JI. A prospective concept and clinical application. J Oral San Francisco: US Dental Health Center, US clinical evaluation of different single-tooth Implantol 2004;30:171-7. Government Printing Office; 1971, Publica- restoration designs on osseointegrated 83.Anner R, Better H, Chaushu G. The clinical tion No: 7902244. p. i-vii and 1-39. implants. A 3-year follow-up of Brane- effectiveness of 6 mm diameter implants. J 51.Strindberg LZ. The dependence of the mark implants. Clin Oral Implants Res Periodontol 2005;76:1013-5. results of pulp therapy on certain factors. 1999;10:453-8. 84.Wennstrom JL, Ekestubbe A, Grondahl K, An analytic study based on radiographic 68.Goodacre CJ, Bernal G, Rungcharas- Karlsson S, Lindhe J. Implant-supported and clinical follow-up examinations. Acta saeng K, Kan JY. Clinical complications single-tooth restorations: a 5-year prospec- Odontol Scand 1956;14(Suppl 21):2-101. in fixed prosthodontics. J Prosthet Dent tive study. J Clin Periodontol 2005;32:567- 52.Orstavik D, Kerkes K, Eriksen HM. The 2003;90:31-41. 74. periapical index: a scoring system for radio- 85.Fugazzotto PA, Beagle JR, Ganeles J, Jaffin graphic assessment of apical periodontitis. Review references R, Vlassis J, Kumar A. Success and failure Endod Dent Traumatol 1986;2:20-34. rates of 9 mm or shorter implants in the 53.Weiger R, Axmann-Krcmar D, Lost C. 69.Schmitt A, Zarb GA. The longitudinal clini- replacement of missing maxillary molars Prognosis of conventional root canal treat- cal effectiveness of osseointegrated dental when restored with individual crowns: ment reconsidered. Endod Dent Traumatol implants for single-tooth replacement. Int J preliminary results 0 to 84 months in func- 1998;14:1-9. Prosthodont 1993;6:197-202. tion. A retrospective study. J Periodontol 54.Eckert SE, Wollan PC. Retrospective review 70.Karlsson U, Gotfredsen K, Olsson C. Single- 2004;75:327-32. of 1170 endosseous implants placed in tooth replacement by osseointegrated Astra 86.Levin L, Pathael S, Dolev E, Schwartz-Arad partially edentulous jaws. J Prosthet Dent Tech dental implants: a 2-year report. Int J D. Aesthetic versus surgical success of sin- 1998;79:415-21. Prosthodont 1997;10:318-24. gle dental implants: 1- to 9-year follow-up. The Journal of Prosthetic Dentistry Torabinejad et al October 2007 309

Pract Proced Aesthet Dent. 2005;17:533-8. implant bone defects. A 2-year prospec- A clinical evaluation of conventional brid- 87.Jemt T, Pettersson P. A 3-year follow-up tive, controlled, randomized follow-up gework. J Oral Rehabil 1990;17:131-6. study on single implant treatment. J Dent report. J Clin Periodontol 2005;32:480-7. 117.Olin PS, Hill EM, Donahue JL. Clinical 1993;21:203-8. 102.Malevez C, Hermans M, Daelemans P. evaluation of resin-bonded bridges: a 88.Cordioli G, Castagna S, Consolati E. Single- Marginal bone levels at Branemark system retrospective study. Quintessence Int tooth implant rehabilitation: a retrospec- implants used for single tooth restora- 1991;22:873-7. tive study of 67 implants. Int J Prosthodont tion. The influence of implant design and 118.Kellett M, Verzijden CW, Smith GA, Creu- 1994;7:525-31. anatomical region. Clin Oral Implants Res gers NH. A multicentered clinical study on 89.Levine RA, Clem DS 3rd, Wilson TG Jr, Hig- 1996;7:162-9. posterior resin-bonded bridges: the ‘Man- ginbottom F, Solnit G. Multicenter retro- 103.Andersson B, Odman P, Lindvall AM, chester trial’. J Dent 1994;22:208-12. spective analysis of the ITI implant system Branemark PI. Five-year prospective study 119.Verzijden CW, Creugers NH, Mulder J. A used for single-tooth replacements: results of prosthodontic and surgical single-tooth multi-practice clinical study on posterior of loading for 2 or more years. Int J Oral implant treatment in general practices resin-bonded bridges: a 2.5-year interim Maxillofac Implants 1999;14:516-20. and at a specialist clinic. Int J Prosthodont report. J Dent Res 1994;73:529-35. 90.Moberg LE, Kondell PA, Kullman L, Heim- 1998;11:351-5. 120.Hussey DL, Linden GJ. The clinical per- dahl A, Gynther GW. Evaluation of single- 104.Andersson B, Odman P, Lindvall AM, formance of cantilevered resin-bonded tooth restorations on ITI dental implants. A Branemark PI. Cemented single crowns bridgework. J Dent 1996;24:251-6. prospective study of 29 patients. Clin Oral on osseointegrated implants after 5 years: 121.Sorensen JA, Kang SK, Torres TJ, Knode H. Implants Res 1999;10:45-53. results from a prospective study on Ce- In-Ceram fixed partial dentures: three-year 91.Wannfors K, Smedberg JI. A prospective raOne. Int J Prosthodont 1998;11:212-8. clinical trial results. J Calif Dent Assoc clinical evaluation of different single-tooth 105.Romanos GE, Nentwig GH. Single molar 1998;26:207-14. restoration designs on osseointegrated replacement with a progressive thread 122.Botelho MG, Chan AW, Yiu EY, Tse ET. implants. A 3-year follow-up of Brane- design implant system: a retrospective cli- Longevity of two-unit cantilevered resin- mark implants. Clin Oral Implants Res nical report. Int J Oral Maxillofac Implants bonded fixed partial dentures. Am J Dent 1999;10:453-8. 2000;15:831-6. 2002;15:295-9. 92.Johnson RH, Persson GR. Evaluation of a 106.Mericske-Stern R, Grutter L, Rosch R, 123.Reuter JE, Brose MO. Failures in full single-tooth implant. Int J Oral Maxillofac Mericske E. Clinical evaluation and prost- crown retained dental bridges. Br Dent J Implants 2000;15:396-404. hetic complications of single tooth repla- 1984;157:61-3. 93.Rodriguez AM, Orenstein IH, Morris HF, cements by non-submerged implants. Clin 124.Hansson O, Moberg LE. Clinical evalua- Ochi S. Survival of various implant-sup- Oral Implants Res 2001;12:309-18. tion of resin-bonded prostheses. Int J ported prosthesis designs following 36 107.Morris HF, Winkler S, Ochi S. A 48-month Prosthodont 1992;5:533-41. months of clinical function. Ann Periodon- multicentric clinical investigation: implant 125.De Kanter RJ, Creugers NH, Verzijden CW, tol 2000;5:101-8. design and survival. J Oral Implantol Van’t Hof MA. A five-year multi-practice 94.Mangano C, Bartolucci EG. Single tooth 2001;27:180-6. clinical study on posterior resin-bonded replacement by Morse taper connec- 108.Dhanrajani PJ, Al-Rafee MA. Single-to- bridges. J Dent Res 1998;77:609-14. tion implants: a retrospective study of 80 oth implant restorations: a retrospective 126.Walter M, Reppel PD, Boning K, Frees- implants. Int J Oral Maxillofac Implants study. Implant Dent 2005;14:125-30. meyer WB. Six-year follow-up of titanium 2001;16:675-80. 109.Scholander S. A retrospective evaluation and high-gold porcelain-fused-to-metal 95.Krennmair G, Schmidinger S, Walden- of 259 single-tooth replacements by the fixed partial dentures. J Oral Rehabil berger O. Single-tooth replacement with use of Branemark implants. Int J Prostho- 1999;26:91-6. the Frialit-2 system: a retrospective clinical dont 1999;12:483-91. 127.Chai J, Chu FC, Newsome PR, Chow analysis of 146 implants. Int J Oral Maxil- 110.Bianco G, Di Raimondo R, Luongo G, TW. Retrospective survival analysis of lofac Implants 2002;17:78-85. Paoleschi C, Piccoli P, Piccoli C, et al. 3-unit fixed-fixed and 2-unit cantilevered 96.Norton MR, Wilson J. Dental implants Osseointegrated implant for single-tooth fixed partial dentures. J Oral Rehabil placed in extraction sites implanted with replacement: a retrospective multicenter 2005;32:759-65. bioactive glass: human histology and clini- study on routine use in private practice. 128.Oginni AO. Failures related to crowns cal outcome. Int J Oral Maxillofac Implants Clin Implant Dent Relat Res 2000;2:152- and fixed partial dentures fabricated in a 2002;17:249-57. 8. Nigerian dental school. J Contemp Dent 97.Andersson L, Emami-Kristiansen Z, 111.Bianchi AE, Sanfilippo F. Single-tooth Pract 2005;6:136-43. Hogstrom J. Single-tooth implant treat- replacement by immediate implant 129.Wolfart S, Bohlsen F, Wegner SM, Kern ment in the anterior region of the maxilla and connective tissue graft: a 1-9-year M. A preliminary prospective evalua- for treatment of tooth loss after trauma: a clinical evaluation. Clin Oral Implants Res tion of all-ceramic crown-retained and retrospective clinical and interview study. 2004;15:269-77. inlay-retained fixed partial dentures. Int J Dent Traumatol 2003;19:126-31. 112.Doring K, Eisenmann E, Stiller M. Func- Prosthodont 2005;18:497-505. 98.Groisman M, Frossard WM, Ferreira HM, tional and esthetic considerations for sin- 130.Marquardt P, Strub JR. Survival rates of de Menezes Filho LM, Touati B. Single-to- gle-tooth Ankylos implant-crowns: 8 years IPS empress 2 all-ceramic crowns and oth implants in the maxillary incisor region of clinical performance. J Oral Implantol fixed partial dentures: results of a 5-year with immediate provisionalization: 2-year 2004;30:198-209. prospective clinical study. Quintessence prospective study. Pract Proced Aesthet 113.Vigolo P, Givani A, Majzoub Z, Cordioli Int 2006;37:253-9. Dent 2003;15:115-22, 124. G. Clinical evaluation of small-diameter 131.Karlsson S. A clinical evaluation of fixed 99.Block M, Finger I, Castellon P, Lirettle implants in single-tooth and multiple- bridges, 10 years following insertion. J D. Single tooth immediate provisional implant restorations: a 7-year retrospec- Oral Rehabil 1986;13:423-32. restoration of dental implants: technique tive study. Int J Oral Maxillofac Implants 132.Valderhaug J. A 15-year clinical evaluation and early results. J Oral Maxillofac Surg 2004;19:703-9. of fixed prosthodontics. Acta Odontol 2004;62:1131-8. 114.Pjetursson BE, Karoussis I, Burgin W, Scand 1991;49:35-40. 100.Ottoni JM, Oliveira ZF, Mansini R, Cabral Bragger U, Lang NP. Patients’ satisfaction 133.Priest G. An 11-year reevaluation of resin- AM. Correlation between placement following implant therapy. A 10-year pro- bonded fixed partial dentures. Int J Perio- torque and survival of single-tooth spective cohort study. Clin Oral Implants dontics Restorative Dent 1995;15:238- implants. Int J Oral Maxillofac Implants Res 2005;16:185-93. 47. 2005;20:769-76. 115.Eshleman JR, Moon PC, Barnes RF. Clini- 134.Kerschbaum T, Haastert B, Marinello CP. 101.Schropp L, Kostopoulos L, Wenzel A, cal evaluation of cast metal resin-bonded Risk of debonding in three-unit resin-bon- Isidor F. Clinical and radiographic perfor- anterior fixed partial dentures. J Prosthet ded fixed partial dentures. J Prosthet Dent mance of delayed-immediate single-tooth Dent 1984;51:761-4. 1996;75:248-53. implant placement associated with peri- 116.Cheung GS, Dimmer A, Mellor R, Gale M. 135.Samama Y. Fixed bonded prosthodon- Torabinejad et al 310 Volume 98 Issue 4

tics: a 10-year follow-up report. Part II. 13. Dent 2002;87:256-63. Clinical assessment. Int J Periodontics 153.Field JW, Gutmann JL, Solomon ES, Raku- 168.Dammaschke T, Steven D, Kaup M, Ott Restorative Dent 1996;16:52-9. sin H. A clinical radiographic retrospective KH. Long-term survival of root-canal- 136.Libby G, Arcuri MR, LaVelle WE, Hebl L. assessment of the success rate of single- treated teeth: a retrospective study over Longevity of fixed partial dentures. J Prost- visit root canal treatment. Int Endod J 10 years. J Endod 2003;29:638-43. het Dent 1997;78:127-31. 2004;37:70-82. 169.Salehrabi R, Rotstein I. Endodontic treat- 137.Probster B, Henrich GM. 11-year follow- 154.Peters OA, Barbakow F, Peters CI. An ment outcomes in a large patient popula- up study of resin-bonded fixed partial analysis of endodontic treatment with tion in the USA: an epidemiological study. dentures. Int J Prosthodont 1997;10:259- three nickel-titanium rotary root canal J Endod 2004;30:846-50. 68. preparation techniques. Int Endod J 170.Kayser AF. Shortened dental arches and 138.Behr M, Leibrock A, Stich W, Rammels- 2004;37:849-59. oral function. J Oral Rehabil 1981;8:457- berg P, Rosentritt M, Handel G. Adhe- 155.Chu CH, Lo EC, Cheung GS. Outcome of 62. sive-fixed partial dentures in anterior and root canal treatment using Thermafil and 171.Witter DJ, van Elteren P, Kayser AF. Migra- posterior areas. Results of an on-going cold lateral condensation filling tech- tion of teeth in shortened dental arches. J prospective study begun in 1985. Clin niques. Int Endod J 2005;38:179-85. Oral Rehabil 1987;14:321-9. Oral Investig 1998;2:31-5. 156.Gagliani MA, Cerutti A, Bondesan A, 172.Oosterhaven SP, Westert GP, Schaub 139.Shugars DA, Bader JD, White BA, Scurria Colombo M, Godio E, Giacomelli G. A RM. Perception and significance of MS, Hayden WJ Jr, Garcia RI. Survival 24-month survey on root canal treatment dental appearance: the case of missing rates of teeth adjacent to treated and performed by NiTi engine driven files and teeth. Community Dent Oral Epidemiol untreated posterior bounded edentulous warm gutta-percha filling associated sys- 1989;17:123-6. spaces. J Am Dent Assoc 1998;129:1089- tem. Minerva Stomatol 2004;53:543-54. 173.Witter DJ, Van Elteren P, Kayser AF, Van 95. 157.Gesi A, Hakeberg M, Warfvinge J, Bergen- Rossum GM. Oral comfort in short- 140.Hochman N, Mitelman L, Hadani PE, holtz G. Incidence of periapical lesions ened dental arches. J Oral Rehabil Zalkind M. A clinical and radiograp- and clinical symptoms after pulpectomy- 1990;17:137-43. hic evaluation of fixed partial dentures -a clinical and radiographic evaluation of 174.Haugejorden O, Rise J, Klock KS. Nor- (FPDs) prepared by dental school stu- 1- versus 2-session treatment. Oral Surg wegian adults’ perceived need for coping dents: a retrospective study. J Oral Rehabil Oral Med Oral Pathol Oral Radiol Endod skills to adjust to dental and non-dental 2003;30:165-70. 2006;101:379-88. life events. Community Dent Oral Epide- 141.Holm C, Tidehag P, Tillberg A, Molin M. 158.Weiger R, Rosendahl R, Lost C. Influence miol 1993;21:57-61. Longevity and quality of FPDs: a retro- of calcium hydroxide intracanal dressings 175.Witter DJ, De Haan AF, Kayser AF, Van spective study of restorations 30, 20, and on the prognosis of teeth with endodonti- Rossum GM. A 6-year follow-up study of 10 years after insertion. Int J Prosthodont cally induced periapical lesions. Int Endod oral function in shortened dental arches. 2003;16:283-9. J 2000;33:219-26. Part II: Craniomandibular dysfunc- 142.Olsson KG, Furst B, Andersson B, 159.Friedman S, Abitbol S, Lawrence HP. tion and oral comfort. J Oral Rehabil Carlsson GE. A long-term retrospective Treatment outcome in endodontics: the 1994;21:353-66. and clinical follow-up study of In-Ce- Toronto Study. Phase 1: initial treatment. 176.Shugars DA, Bader JD, Phillips SW Jr, ram Alumina FPDs. Int J Prosthodont J Endod 2003;29:787-93. White BA, Brantley CF. The consequences 2003;16:150-6. 160.Farzaneh M, Abitbol S, Friedman S. Treat- of not replacing a missing posterior tooth. 143.Walton TR. An up to 15-year longitudinal ment outcome in endodontics: the To- J Am Dent Assoc 2000;131:1317-23. study of 515 metal-ceramic FPDs: Part 1. ronto study. Phases I and II: Orthograde 177.Witter DJ, Creugers NH, Kreulen CM, de Outcome. Int J Prosthodont 2002;15:439- retreatment. J Endod 2004;30:627-33. Haan AF. Occlusal stability in shortened 45. 161.Marquis VL, Dao T, Farzaneh M, Abitbol dental arches. J Dent Res 2001;80:432-6. 144.De Backer H, Van Maele G, De Moor N, S, Friedman S. Treatment outcome in 178.Gragg KL, Shugars DA, Bader JD, Elter JR, Van den Berghe L, De Boever J. A 20-year endodontics: the Toronto Study. Phase III: White BA. Movement of teeth adjacent to retrospective survival study of fixed partial initial treatment. J Endod 2006;32:299- posterior bounded edentulous spaces. J dentures. Int J Prosthodont 2006;19:143- 306. Dent Res 2001;80:2021-4. 53. 162.Stoll R, Betke K, Stachniss V. The influ- 179.Davis DM, Fiske J, Scott B, Radford DR. 145.Barrack G, Bretz WA. A long-term pro- ence of different factors on the survival of The emotional effects of tooth loss in a spective study of the etched-cast restora- root canal fillings: a 10-year retrospective group of partially dentate people: a quan- tion. Int J Prosthodont 1993;6:428-34. study. J Endod 2005;31:783-90. titative study. Eur J Prosthodont Restor 146.Ashkenaz PJ. One-visit endodon- 163.Doyle SL, Hodges JS, Pesun IJ, Law AS, Dent 2001;9:53-7. tics--a preliminary report. Dent Surv Bowles WR. Retrospective cross sec- 180.Aquilino SA, Shugars DA, Bader JD, White 1979;55:62-7. tional comparison of initial nonsurgical BA. Ten-year survival rates of teeth adja- 147.Rudner WL, Oliet S. Single-visit endo- endodontic treatment and single-tooth cent to treated and untreated posterior dontics: a concept and a clinical study. implants. J Endod 2006;32:822-7. bounded edentulous spaces. J Prosthet Compend Contin Educ Dent 1981;2:63-8. 164.Lazarski MP, Walker WA 3rd, Flores CM, Dent 2001;85:455-60. 148.Oliet S. Single-visit endodontics: a clinical Schindler WG, Hargreaves KM. Epide- 181.Sarita PT, Kreulen CM, Witter D, Creugers study. J Endod 1983;9:147-52. miological evaluation of the outcomes NH. Signs and symptoms associated with 149.Teo CS, Chan NC, Lim SS. Success rate in of nonsurgical root canal treatment in a TMD in adults with shortened dental endodontic therapy--a retrospective study. large cohort of insured dental patients. J arches. Int J Prosthodont 2003;16:265- Part I. Dent J Malays 1986;9:7-10. Endod 2001;27:791-6. 70. 150.Michanowicz AE, Michanowicz JP, Micha- 165.Waltimo TM, Boiesen J, Eriksen HM, 182.Hattori Y, Satoh C, Seki S, Watanabe nowicz AM, Czonstkowsky M, Zullo TP. Orstavik D. Clinical performance of 3 end- Y, Ogino Y, Watanabe M. Occlusal and Clinical evaluation of low-temperature odontic sealers. Oral Surg Oral Med Oral TMJ loads in subjects with experimen- thermoplasticized injectable gutta-per- Pathol Oral Radiol Endod 2001;92:89-92. tally shortened dental arches. J Dent Res cha: a preliminary report. J Endod 166.Alley BS, Kitchens GG, Alley LW, Eleazer 2003;82:532-6. 1989;15:602-7. PD. A comparison of survival of teeth fol- 183.Sarita PT, Witter DJ, Kreulen CM, Van’t 151.Benenati FW, Khajotia SS. A radiographic lowing endodontic treatment performed Hof MA, Creugers NH. Chewing abil- recall evaluation of 894 endodontic cases by general dentists or by specialists. Oral ity of subjects with shortened dental treated in a dental school setting. J Endod Surg Oral Med Oral Pathol Oral Radiol arches. Community Dent Oral Epidemiol 2002;28:391-5. Endod 2004;98:115-8. 2003;31:328-34. 152.Travassos RM, Caldas Ade F, de Albuqu- 167.Aquilino SA, Caplan DJ. Relationship be- 184.Wolfart S, Heydecke G, Luthardt RG, erque DS. Cohort study of endodontic tween crown placement and the survival Marre B, Freesmeyer WB, Stark H, et al. therapy success. Braz Dent J 2003;14:109- of endodontically treated teeth. J Prosthet Effects of prosthetic treatment for short- The Journal of Prosthetic Dentistry Torabinejad et al October 2007 311

ened dental arches on oral health-related 193.Chang M, Odman PA, Wennstrom JL, An- 201.Szentpetery AG, John MT, Slade GD, Setz quality of life, self-reports of pain and jaw dersson B. Esthetic outcome of implant- JM. Problems reported by patients before disability: results from the pilot-phase supported single-tooth replacements and after prosthodontic treatment. Int J of a randomized multicentre trial. J Oral assessed by the patient and by prosth- Prosthodont 2005;18:124-31. Rehabil 2005;32:815-22. odontists. Int J Prosthodont 1999;12:335- 185.Barbakow FH, Cleaton-Jones P, Friedman 41. Corresponding author: D. An evaluation of 566 cases of root ca- 194.Dugas NN, Lawrence HP, Teplitsky P, Dr Shane N. White nal therapy in general dental practice. 1. Friedman S. Quality of life and satisfac- UCLA School of Dentistry Diagnostic criteria and treatment details. J tion outcomes of endodontic treatment. J 10833 LeConte Ave Endod 1980;6:456-60. Endod 2002;28:819-27. CHS 23-010 186.Wong M, Lytle WR. A comparison of 195.Watkins CA, Logan HL, Kirchner HL. Anti- Los Angeles, CA 90095-1668 anxiety levels associated with root canal cipated and experienced pain associated Fax: 310-206-3644 therapy and oral surgery treatment. J with endodontic therapy. J Am Dent Assoc E-mail: [email protected] Endod 1991;17:461-5. 2002;133:45-54. 187.Ekfeldt A, Carlsson GE, Borjesson G. Clin- 196.Sonoyama W, Kuboki T, Okamoto S, Acknowledgements ical evaluation of single-tooth restorations Suzuki H, Arakawa H, Kanyama M, et al. The authors gratefully acknowledge the supported by osseointegrated implants: a Quality of life assessment in patients with financial support of the ADA Foundation; the retrospective study. Int J Oral Maxillofac implant-supported and resin-bonded Editorial Council for The Journal of Prosthetic Implants 1994;9:179-83. fixed prosthesis for bounded edentu- Dentistry for giving permission to allow simul- 188.Andersson B. Implants for single-tooth lous spaces. Clin Oral Implants Res taneous publication of a summary of this data replacement. A clinical and experimental 2002;13:359-64. in another journal; their external consultants study on the Branemark CeraOne System. 197.Vermylen K, Collaert B, Linden U, Bjorn Steven Aquilino (University of Iowa), Ross Swed Dent J Suppl 1995;108:1-41. AL, De Bruyn H. Patient satisfaction and Beirne (University of Washington), John DaSil- 189.Lobb WK, Zakariasen KL, McGrath PJ. quality of single-tooth restorations. Clin va (Harvard University), Jeffrey Hutter (Boston Endodontic treatment outcomes: do Oral Implants Res 2003;14:119-24. University), Larz Spangberg (University of patients perceive problems? J Am Dent 198.Schropp L, Isidor F, Kostopoulos L, Wen- Connecticut), and George Zarb (University of Assoc 1996;127:597-600. zel A. Patient experience of, and satisfac- Toronto); the invaluable assistance of Eliza- 190.Peretz B, Moshonov J. Dental anxiety tion with, delayed-immediate vs. delayed beth Akhparyan (UCLA), Dominic Cote (Loma among patients undergoing endodontic single-tooth implant placement. Clin Oral Linda University), Mohammad Torabinejad treatment. J Endo 1998;24:435-7. Implants Res 2004;15:498-503. (The College of William and Mary), and Mar- 191.Stabholz A, Peretz B. Dental anxiety 199.Udoye CI, Oginni AO, Oginni FO. Dental jorie Sweet (Loma Linda University); as well as among patients prior to different dental anxiety among patients undergoing the considerable efforts of all those who have treatments. Int Dent J 1999;49:90-4. various dental treatments in a Nigerian preceded us in trying to measure and interpret 192.Chang M, Wennstrom JL, Odman P, teaching hospital. J Contemp Dent Pract patient outcomes. Andersson B. Implant supported single- 2005;6:91-8. tooth replacements compared to con- 200.Bragger U, Krenander P, Lang NP. tralateral natural teeth. Crown and soft Economic aspects of single-tooth Copyright © 2007 by the Editorial Council for tissue dimensions. Clin Oral Implants Res replacement. Clin Oral Implants Res The Journal of Prosthetic Dentistry. 1999;10:185-94. 2005;16:335-41.

Noteworthy Abstracts of the Current Literature Repeated distraction osteogenesis for excessive vertical alveolar augmentation: a case report

Iida S, Nakano T, Amano K, Kogo M. Int J Oral Maxillofac Implants 2006;21:471-5.

In this article, a procedure involving 2-stage alveolar distraction osteogenesis using eccentric distraction devices for the augmentation of resorbed transplanted iliac bone following mandibular tumor resection is presented. A 6-month consolidation period was allowed between the first and second distractions, and endosseous implants were placed 4 months after the second distraction. Computerized tomographic images obtained before the implantation revealed that, 10 months after the first distraction, the bone generated still showed lower density compared with the basal bone, but the bone from both distractions showed enough maturity for implantation. It may be concluded that 2-stage alveolar distraction osteogenesis can be a useful and safe procedure for excessive alveolar lengthening if a suf- ficiently long consolidation period is allowed.

Reprinted with permission of Quintessence Publishing.

Torabinejad et al