CHAPTER 32 Biodigital Orthodontics: Integrating Technology with Diagnosis 975 CASE STUDY 32-1—cont’d C Final D Initial x-rays E Initial model FIGURE 32-45, cont’d Continued 976 CHAPTER 32 Biodigital Orthodontics: Integrating Technology with Diagnosis CASE STUDY 32-1—cont’d F Therapeutic model G Setup H Final x-rays FIGURE 32-45, cont’d CHAPTER 32 Biodigital Orthodontics: Integrating Technology with Diagnosis 977 CASE STUDY 32-1—cont’d A Initial B Therapeutic FIGURE 32-46 A–F, Mutilated dentition, Damon bracket system, 0.014-inch Damon copper- nickel-titanium (CuNiTi), followed by 0.16- × 0.22-inch CuNiTi AF 35°C lower wire and upper Sure- Smile prescriptive archwire 17- × 25-inch CuNiTi AF 35° C followed by 19- × 25-inch CuNiTi AF 35° C. Continued 978 CHAPTER 32 Biodigital Orthodontics: Integrating Technology with Diagnosis CASE STUDY 32-1—cont’d C Final D Initial model FIGURE 32-46, cont’d CHAPTER 32 Biodigital Orthodontics: Integrating Technology with Diagnosis 979 CASE STUDY 32-1—cont’d E Therapeutic model F Setup FIGURE 32-46, cont’d 980 CHAPTER 32 Biodigital Orthodontics: Integrating Technology with Diagnosis REFERENCES 9. Balut N, Klapper L, Sandrik J, Bowman D. Variations in bracket place- ment in the preadjusted orthodontic appliance. Am J Orthod Dentofacial 1. Mah J, Sachdeva R. Computer-assisted orthodontic treatment: the Orthop. 1992;102(1):62–67. SureSmile process. Am J Orthod Dentofacial Orthop. 2001;120(1): 10. Cash A, Good S, Curtis R, McDonald F. An evaluation of slot size 85–87. in orthodontic brackets—are standards as expected? Angle Orthod. 2. Sachdeva R. Sure-Smile: technology-driven solution for orthodontics. Tex 2004;74(4):450–453. Dent J. 2002;119(7):608–615. 11. Matasa CG. Preadjusted appliances: one shoe fits all? (II) Can brackets 3. Sachdeva R, Frugé JF, Frugé AM, et al. SureSmile: a report of clinical alone make them … straight? Orthod Materials Insider. 1994;7(3). findings. J Clin Orthod. 2005;39(5):297–314. 12. Scholz R, Sarver D. Interview with an Insignia doctor: David M. Sarver. 4. Sachdeva RC. SureSmile’s promise: digital care solutions for the ortho- Am J Orthod Dentofacial Orthop. 2009;136(6):853–856. dontic industry. Orthod CYBER Journal. 2001. 13. Kanavakis G, Spinos P, Polychronopoulou A, et al. Orthodontic journals 5. JCO INTERVIEWS Dr. Rohit CL. Sachdeva on a total orthodontic with impact factors in perspective: trends in the types of articles and author- care solution enabled by breakthrough technology. J Clin Orthod. ship characteristics. Am J Orthod Dentofacial Orthop. 2006;130(4):516–522. 2000;34(4):223–232. 14. Saxe A, Louie L, Mah J. Efficiency and effectiveness of SureSmile. World J 6. Scholz R, Sachdeva RC. Interview with an innovator: SureSmile Chief Orthod. 2010;11(1):16–22. Clinical Officer Rohit C. L. Sachdeva. Am J Orthod Dentofacial Orthop. 15. Alford TJ, Roberts WE, Hartsfield JK, et al. Clinical outcomes for patients 2010;138:231–238. finished with SureSmile™ method compared with conventional fixed 7. Sachdeva R, Feinberg MP. Reframing clinical patient management with orthodontic therapy. Angle Orthod. 2011;81(3):383–388. SureSmile technology. PSCO NewsWire. 2009;2(1). Available at http:// 16. Sachdeva R, Aranha SL, Egan ME, et al. Treatment time: SureSmile vs www.pcsortho.org/newswire/March-09.cfm. conventional. Orthodontics (Chic.). 2012;13:72–85. 8. Hodge T, Dhopatkar A, Rock W, Spary D. A randomized clinical trial 17. Patel N. Linear Analysis of Anterior Root Resorption Utilizing Cone-Beam comparing the accuracy of direct versus indirect bracket placement. J CT: SureSmile Versus Conventional Edgewise. M.S. Thesis, University of Orthod. 2004;31(2):132–137. Oklahoma; 2010. PART SIX Orthodontic Retention and Posttreatment Changes 33 Stability, Retention, and Relapse Donald R. Joondeph, Greg Huang, and Robert Little OUTLINE History of Retention, 981 Theory 7: Corrections Carried out during Periods of Occlusal School, 981 Growth Are Less Likely to Relapse, 983 Apical Base School, 981 Theory 8: Arch Form, Particularly the Mandibular Mandibular Incisor School, 982 Arch, Cannot Be Permanently Altered with Appliance Musculature School, 982 Therapy, 983 Retention Theories Proposed Other Factors Related to Retention, 983 in the Literature, 982 Tooth-Size Discrepancies, 983 Theory 1: Teeth That Have Been Moved Tend to Return to Interproximal Reduction, 983 Their Former Position, 982 Growth Factors and Posttreatment Change, 984 Theory 2: Elimination of the Cause of the Malocclusion Third Molars, 984 Will Prevent Recurrence, 982 Duration of Retention, 984 Theory 3: Malocclusion Should Be Overcorrected, 982 Occlusal Adjustment, 984 Theory 4: Proper Occlusion Is an Important Factor in UW Postretention Registry: Lessons Learned, 984 Holding Teeth in Their Corrected Positions, 982 Clinical Applications of Retention, 989 Theory 5: Bone and Adjacent Tissues Must Be Allowed to Retention Appliances, 991 Reorganize around Newly Positioned Teeth, 982 Positioner in Retention Planning, 994 Theory 6: If the Lower Incisors Are Placed over Duration of Retention, 994 Basal Bone, They Are More Likely to Remain in Recovery after Relapse, 994 Good Alignment, 983 Summary, 995 A working definition of retention in relation to orthodontics the specific factors causing relapses.” Different schools of thought might be stated as follows: the holding of teeth in optimal aes- have existed over time, and present-day concepts generally com- thetic and functional positions. bine several of the following historic concepts regarding retention. The requirements for retention are often decided at the time of diagnosis and treatment planning. The correct problem list or diag- Occlusal School nosis, a logical treatment plan, and the timing of treatment must be Kingsley2 stated, “The occlusion of the teeth is the most potent directed toward achieving favorable aesthetics, ideal function, and, factor in determining the stability in a new position.” Many as much as possible, the permanent maintenance of these goals. early investigators3–18 agreed that proper occlusion was of pri- Incorrect diagnosis or treatment, on the other hand, can compli- mary importance in retention. cate the requirements for retention. For instance, gross expansion of the dental arches, severe changes in arch form, incomplete reso- Apical Base School lution of anteroposterior malrelationships, and incomplete correc- In the middle 1920s, a second school of thought formed sec- tion of dental rotations may require additional retentive measures. ondary to the writings of Axel Lundstrom,19 who suggested that the apical base was one of the most important factors in HISTORY OF RETENTION the correction of malocclusion and the maintenance of a cor- rected occlusion. McCauley20 also suggested that intercanine For many years, clinicians did not agree about the need for reten- width and intermolar widths should be maintained as origi- tion. Hellman1 said, “We are in almost complete ignorance of nally presented to minimize retention problems. Strang and 981 982 CHAPTER 33 Stability, Retention, and Relapse Thompson21 further confirmed and substantiated this concept. the individual to be able to breathe. Dentofacial changes asso- Finally, Nance22 also noted that, “arch length may be perma- ciated with this functional alteration appear to become more nently increased only to a limited extent.” severe with age28 and are a challenge to diagnose accurately and to treat and retain successfully. This retention issue has been Mandibular Incisor School discussed by Lopez-Gavito and colleagues,31 who conducted a Grieve23 and Tweed24,25 suggested that the mandibular incisors long-term evaluation of patients with initial open bite maloc- must be placed and kept upright over basal bone to maximize clusions. Despite attempts to control posterior maxillary verti- their stability. cal changes during active treatment and retention, the authors of this study found that 35% of the patients with an initial open Musculature School bite had an open bite of 3 mm or more 10 years out of retention. Rogers26 introduced a consideration of the necessity of establish- ing proper muscular balance. Others corroborated his thoughts. Theory 3: Malocclusion Should Be Overcorrected Over time, orthodontists have come to realize that retention is A common practice of many orthodontists is to overcorrect not separate from active orthodontic treatment; rather, retention a Class II malocclusion into an edge-to-edge incisor relation- is part of treatment itself and must be included in treatment plan- ship. One must be aware, however, that an overcorrection such ning. Stability has become a primary objective in orthodontic as this could be the result of muscle memory, rather than the treatment; without it, ideal function, optimal aesthetics, or both achievement of a true skeletal or dental correction. The use of may be lost.27 Care must exercised to establish a proper occlusion prolonged Class II elastics, for instance, may produce a for- within the bounds of normal muscle balance and with careful ward postural displacement of the mandible, which is difficult regard given to the apical base, as well as to the relationship of the to detect until elastics have been discontinued long enough to maxillary and mandibular bases to one another. allow normal mandibular posture to return, emphasizing the need to check patients in the centric relation position. RETENTION THEORIES PROPOSED Overcorrection of a deep overbite is an accepted procedure by IN THE LITERATURE many clinicians. Satisfactory maintenance