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The International Journal of Periodontics & Restorative Dentistry

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The International Journal of Periodontics & Restorative Dentistry Ohyama.qxd 12/7/06 4:38 PM Page 60 The International Journal of Periodontics & Restorative Dentistry Ohyama.qxd 12/7/06 4:38 PM Page 61 61 Recreating an Esthetic Smile: A Multidisciplinary Approach Hiroe Ohyama, DMD, MMSc, PhD* The esthetic restoration/rehabilitation Shigemi Nagai, DDS, MS, PhD* of a patient with a functionally com- Hiro Tokutomi, RDT** promised dentition frequently involves Michael Ferguson, DMD*** a multidisciplinary approach. The suc- cessful integration of esthetics and function does not emerge by chance, but rather as a result of the meticulous development of clearly defined ana- Today’s dental patients are demanding a youthful, attractive smile. The esthetic tomic parameters and their subse- rehabilitation of patients with functionally compromised dentitions frequently quent incorporation into the design of involves a multidisciplinary approach. The realization of esthetic objectives in mul- the prosthesis.1–4 tidisciplinary cases represents a considerable clinical challenge. To a great extent, The restorative and periodontal proper case selection and careful multidisciplinary treatment planning can govern the predictability of procedures. A team approach that includes the clinicians, the elements, such as incisal length, incisal laboratory technician, and the patient is essential to achieve the desired results. plane, incisal profile, incisal display, This clinical report demonstrates a successful multidisciplinary approach to re- tooth shape and color, tooth propor- creating an esthetic smile of a patient whose anterior maxillary dentition had been tion, tooth-to-tooth proportions, gin- functionally and esthetically compromised by prosthetic and periodontal prob- gival architecture, and gingival display lems. (Int J Periodontics Restorative Dent 2007;27:61–69.) should be considered in the creation of a pleasing smile. The incisal plane should be harmonized with the lower lip in proper incisal length and profile. The incisal display should also take into account the patient’s age and gender. Ideally, tooth-to-tooth proportions *Instructor, Harvard School of Dental Medicine, Department of Restorative Dentistry and should follow the golden proportion.5 Biomaterials Sciences, Boston, Massachusetts. **Cusp Dental Laboratory, Malden, Massachusetts. Periodontal treatment provides part of ***Associate Clinical Professor, Department of Prosthodontics, New York University College the solution to commonly encountered of Dentistry, New York, New York. esthetic issues,6 such as excessive gin- gival display,7–11 asymmetric gingival Correspondence to: Hiroe Ohyama, Harvard School of Dental Medicine, Department of 12–14 Restorative Dentistry and Biomaterials Sciences, 188 Longwood Avenue, Boston, MA architecture, the loss of papil- 02115; fax: +617-432-0901; e-mail: [email protected]. lae,15,16 and the exposure of root sur- Volume 27, Number 1, 2007 Ohyama.qxd 12/7/06 4:38 PM Page 62 62 Fig 1 Pretreatment clinical appearance, frontal view. A healthy, 68-year-old male patient presented with the desire to improve the esthetics of his maxillary dentition. faces.17,18 An evaluation of the gingival preoperative treatment plan allows the architecture and any subsequent plans clinician to identify areas of concern, for its modification should be consid- outline the desired protocol for restora- ered based on the amount of gingival tions, and communicate desired para- display and ability to achieve a desir- meters to a laboratory technician.19 A able gingival architecture and tooth team approach by clinicians, laboratory proportion. For instance, in the pres- technicians, and the patient is neces- ence of a good crown-to-root ratio, sary to achieve desired results when a esthetic crown lengthening can pro- multidisciplinary approach is indicated. vide an opportunity to develop appro- This clinical report demonstrates a priate proportions of the anterior teeth, successful multidisciplinary approach along with pleasing gingival symmetry. to recreate an esthetic smile in a Appropriate case selection and patient whose maxillary anterior den- careful treatment planning are critical tition had been functionally and esthet- to a successful outcome and patient ically compromised as a result of pros- satisfaction in multidisciplinary cases. thetic and periodontal problems. Prior to finalizing the esthetic design, a treatment plan should be developed with comprehensive examinations and smile analysis, as well as a good under- standing of the patient’s expectations. The use of diagnostic elements and a The International Journal of Periodontics & Restorative Dentistry Ohyama.qxd 12/7/06 4:38 PM Page 63 63 Figs 2a and 2b Pretreatment facebow registration. The study casts were mounted on a semiadjustable articulator via a face- bow transfer. Clinical report Periodontal evaluation erally, a Class I canine relationship on the right, and an end-to-end canine Patient description and The patient showed generalized gin- relationship on the left. Overbite was examination gival inflammation and generalized 1 mm, and overjet was 1.5 mm. mild horizontal bone loss, with probing Maximum intercuspation and centric A healthy, 68-year-old male patient depths ranging from 1 to 3 mm, except occlusion (centric relation) were coin- presented with the desire to improve at the distal aspects of the mandibular cident. Bilateral partial group function the esthetics of his maxillary dentition. right and left second molars, which was observed on lateral excursions A clinical examination revealed sev- exhibited probing depths of 4 mm and with nonworking interferences. The eral fractured teeth (maxillary right and bleeding on probing. The patient had incisal edges of the mandibular incisors left central incisors, right lateral incisor, an adequate amount of keratinized guided against the lingual surfaces of and right first premolar); defective gingiva in the maxillary anterior and the maxillary incisors during protru- restorations (maxillary right first mild gingival recession in the mandibu- sion, although posterior interferences and second molars, right second pre- lar anterior. were present. The patient had exten- molar, left lateral incisor, left first and sive incisal occlusal wear in both arches second premolars, left second molar, (see Fig 1). However, the patient was mandibular left first and second Occlusal evaluation comfortable with the present vertical molars, left second premolar, and right dimension and had no muscular dis- second molar); and caries lesions (max- The study casts were mounted on a comfort or clicking/crepitus in the tem- illary right and left canines) (Fig 1). No semiadjustable articulator via a face- poromandibular joints. The patient intraoral pathology was noted clini- bow transfer (Fig 2). The patient had reported no parafunctional habits. cally or radiographically. Angle Class I molar relationships bilat- Volume 27, Number 1, 2007 Ohyama.qxd 12/7/06 4:38 PM Page 64 64 Fig 3 Pretreatment clinical appearance, smile in frontal view. Note the revealing asymmetric gingival architecture and the moderate amount of gingival display upon smiling. Smile analysis positioned 1.5 mm to the right of the midfacial vertical plane, and the Objective smile analysis mandibular midline was 2 mm to the The patient presented with a high left of the midfacial vertical plane. smile line and moderate gingival dis- Fractures and discoloration of maxil- play of 2 mm when smiling (Fig 3). lary anterior restorations and mis- The incisal edges of the maxillary matched crown colors also compro- anterior teeth were not in harmony mised his smile (see Figs 1 and 3). with the lower lip line, and there was no incisor crown display in rest posi- Subjective smile analysis tion. The patient had a sufficient quan- The patient was unhappy with the tity of keratinized gingiva in his max- appearance of his maxillary anterior illary anterior region, but the gingival teeth. He did not like the short crowns, marginal line was not harmonized with discoloration, and mismatched color of his upper lip. The ideal height-to- his anterior crowns. He wanted to cor- width ratio of the maxillary central rect the fractures and wear of his teeth incisors is 75% to 83%, yet the patient and desired a more youthful smile. The had a 100% ratio. The short clinical resin composite restorations in the crown height of the maxillary incisors maxillary incisors had fractured several compromised his esthetics. Maxillary times during the previous 5 years, and and mandibular midlines were not the patient desired a longer-lasting coincident. The maxillary midline was restorative solution. The International Journal of Periodontics & Restorative Dentistry Ohyama.qxd 12/7/06 4:38 PM Page 65 65 Considerations in treatment Occlusal harmony planning The patient had bilateral partial group Complex treatment plans frequently function and posterior interferences on require multidisciplinary therapy. The protrusion and lateral excursions. One of establishment of an esthetic scheme the ultimate goals was to establish a must be considered an integral com- functional occlusion by eliminating inter- ponent of the diagnostic phase. Once ferences and creating a mutually pro- esthetic objectives are defined, adjunc- tected occlusion. In this case, the verti- tive treatment considerations are cal dimension of occlusion (VDO) would developed to support the desired be maintained because the patient was restorative outcome.3 In the present comfortable with the current VDO and case, fractured teeth, defective
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