For nongrowing patients with skeletal Class II

Transcription

1 CASE REPORT Treatment of anterior open bite and multiple missing teeth with lingual fixed appliances, double jaw surgery, and dental implants Min-Ho Jung, a Un-Bong Baik, b and Sug-Joon Ahn c Seoul, Korea The treatment of adult patients with severe anterior open bite frequently requires orthognathic surgery, especially when the chin is retruded severely. If a patient has multiple missing posterior teeth, it is difficult to control the occlusal plane because it is challenging to obtain anchorage during orthodontic treatment. We report on a 25- year-old woman who had a skeletal Class II malocclusion, severe anterior open bite, vertical maxillary asymmetry, and severe dental caries on her molars. There was no posterior occlusal contact between the maxillary and mandibular molars since 5 of her molars had to be extracted because of severe caries. Lingual fixed appliances and double jaw surgery were performed to treat her skeletal and dental problems, and dental implants helped restore her masticatory function. Pretreatment, posttreatment, and retention photographs demonstrate effective, esthetically pleasing, and stable treatment results. (Am J Orthod Dentofacial Orthop 2013;143:S125-36) For nongrowing patients with skeletal Class II malocclusions, there are 2 possible treatment approaches: (1) orthodontic camouflage, which consists of retraction of the maxillary incisors to improve both the dental occlusion and the facial esthetics but does not correct the underlying skeletal problem; and (2) orthognathic surgery to reposition the mandible and/or the maxilla. Skeletal Class II problems are frequently due to mandibular deficiency or downward and backward rotation of the mandible accompanied by excessive maxillary vertical growth. Surgical treatment for these patients, therefore, consists of mandibular advancement, superior repositioning of the maxilla, or a combination of both. Jaw surgery combined with orthodontic treatment can produce a more ideal skeletal relationship than a Clinical assistant professor, Department of Orthodontics, Dental Research Institute and School of Dentistry, Seoul National University, Seoul, Korea; private practice, Seoul, Korea. b Private practice, Seoul, Korea. c Associate professor, Department of Orthodontics, Dental Research Institute and School of Dentistry, Seoul National University, Seoul, Korea. The authors report no commercial, proprietary, or financial interest in the products or companies described in this article. Reprint requests to: Sug-Joon Ahn, Department of Orthodontics, Dental Research Institute and School of Dentistry, Seoul National University, Yunkeun-Dong, Chongro-Ku, Seoul , Korea (ROK); , titoo@snu. ac.kr. Submitted, October 2011; revised and accepted, November /$36.00 Copyright Ó 2013 by the American Association of Orthodontists. orthodontic camouflage, with the mandible more anteriorly positioned and the mandibular incisors in a more ideal position relative to the basal bone. 1 Treatment of anterior open bite has long been considered a challenge to orthodontists, because a successful and well-maintained result is difficult to achieve. In particular, the combination of a sagittal skeletal discrepancy and a skeletal open bite requires the highest degree of diagnostic and clinical skill to treat. The prevalence of anterior open bite ranges from 1.5% to 11% among various ages and populations. 2 Orthodontists have many treatment options for treating open bite. High-pull headgear, 3 posterior bite-blocks, 4 functional appliances, 5 multiloop edgewise archwires, 6 mini-implants, 7 and orthognathic surgery 8 are possible modalities for treating an anterior open bite. However, if many of the patient s posterior teeth have been extracted or are severely damaged, solving the patient s occlusal and esthetic problems by orthodontic treatment alone becomes nearly impossible. This case report describes the use of lingual fixed appliances and double jaw surgery to resolve an anterior open bite, a vertical maxillary asymmetry, and an anteroposterior skeletal discrepancy in an adult Class II patient. This 25-year-old woman had a retruded mandible and posterior teeth that were damaged by caries. Because of the severity of her caries, 5 of her molars had to be extracted, and there was no occlusal stop in the molar region. The posterior occlusion was restored with dental implants after surgical orthodontic treatment. S125

2 S126 Jung, Baik, and Ahn Fig 1. Pretreatment facial and intraoral photographs. Fig 2. Pretreatment study models. April 2013 Vol 143 Issue 4 Supplement 1 American Journal of Orthodontics and Dentofacial Orthopedics

3 Jung, Baik, and Ahn S127 Fig 3. Pretreatment radiographs. Fig 4. Pretreatment lateral (A) and posteroanterior (B) cephalometric tracings. DIAGNOSIS AND ETIOLOGY This healthy woman was referred to our clinic for orthodontic evaluation with a chief complaint of impaired occlusion because of an anterior open bite and severe dental caries. She had a retruded mandible and facial asymmetry (Fig 1). Hyperactivity of the mentalis muscle American Journal of Orthodontics and Dentofacial Orthopedics April 2013 Vol 143 Issue 4 Supplement 1

4 S128 Jung, Baik, and Ahn Table. Summary of cephalometric analysis Norm* Pretreatment Posttreatment Postretention Bjork sum ( ) Facial height ratio (%) ANB ( ) A to N perpendicular (mm) Pog to N perpendicular (mm) U1 to FH ( ) U1 to SN ( ) U1 to Sto 0 (mm) L1 to A-Pog ( ) IMPA ( ) Interincisal angle ( ) Nasolabial angle ( ) Upper lip to E-line (mm) Lower lip to E-line (mm) Upper occlusal plane to maxillary incisor ( ) Lower occlusal plane to mandibular incisor ( ) Upper occlusal plane to AB ( ) AB to FH ( ) FH to upper occlusal plane ( ) Sn 0 -Sto 0 : Sto 0 -Me 0 1:1.90 1:1.94 1:1.85 1:1.83 FH, Frankfort horizontal plane; SN, sella-nasion plane; Sto 0, soft-tissue stomion; IMPA, mandibular incisor to mandibular plane angle; OP, occlusal plane; Sn 0, soft-tissue subnasion; Me 0, soft-tissue menton. *Mean value for Korean women. was observed with the lips sealed. From the frontal view, she exhibited both occlusal plane canting and lip-line canting, but there was no dental midline deviation during smile. She was aware of her retrusive chin and lip incompetence. Intraorally, she had an anterior open bite ( 2.0 mm) and multiple dental caries. Her maxillary left first and second molars, maxillary right second molar, and mandibular left and right first molars were severely damaged by dental caries. Her canine relationship was Class II on both sides (Fig 2). The occlusal examination showed interdental spacing in the mandibular anterior region. The patient did not have an unusual medical history. The functional assessment showed no limitation of movement during jaw opening and no apparent signs and symptoms of temporomandibular disorders. Her panoramic radiograph showed multiple root rests, an impacted mandibular right third molar, and distal inclination of the condylar head (Fig 3). The mandibular right third molar was tipped mesially and impacted horizontally. The lateral cephalometric analysis (Fig 4 and Table) showed a skeletal Class II relationship (ANB angle, 9.2 ) caused by a retrognathic mandible (Pog to N perpendicular, 11.8 mm). Her facial pattern was hyperdivergent, as evidenced by a facial height ratio of The maxillary and mandibular incisors were normally positioned. Posteroanterior cephalometric analysis (Fig 4) showed a slight chin point deviation from the skeletal midline because of vertical maxillary asymmetry. She also had an asymmetric shape of the mandibular angle region. TREATMENT OBJECTIVES The treatment objectives were to obtain a Class I canine relationship with normal overbite and overjet, resolve the mandibular interdental spacing, improve the facial profile, restore lip competence, and rehabilitate her posterior occlusion while correcting the facial profile. TREATMENT ALTERNATIVES The first alternative was orthognathic surgery because of her skeletal discrepancy. Maxillary asymmetrical impaction with clockwise rotation, which would induce mandibular autorotation, correct the vertical asymmetry, and improve the nasolabial angle, and concurrent mandibular advancement surgery could be planned to improve her facial profile. Advancement and vertical reduction genioplasty would move the chin forward and reduce the long lower facial height. Additional mandibular angle osteotomies would be needed to correct the asymmetry of her mandibular angle region. This option would not only correct the Class II occlusal problems, but also significantly improve her facial profile. The second option consisted of orthodontic camouflage to obtain proper overbite and overjet, and dental implants placed after orthodontic treatment. Although April 2013 Vol 143 Issue 4 Supplement 1 American Journal of Orthodontics and Dentofacial Orthopedics

5 Jung, Baik, and Ahn S129 Fig 5. Presurgical facial and intraoral photographs. this treatment option would improve the occlusal relationship and obtain a positive overbite, it would not significantly improve her profile and lip competence because the change in chin position would be minimal. In addition, this option could not correct the vertical maxillary asymmetry. If there had been teeth in the molar region, orthodontic mini-implants could have helped to improve the facial profile and control the vertical maxillary asymmetry without surgical treatment. As a result, the first option was selected because the patient s main concern was facial esthetics. TREATMENT PROGRESS Initially, the patient s maxillary left first and second molars, maxillary right second molar, and mandibular left and right first molars, which were severely damaged by dental caries, were extracted. Edgewise lingual brackets with in slots (Ormco, Glendora, Calif) were inserted on the lingual side of the teeth, because the patient was eager to use an invisible appliance. Initially, in nickel-titanium archwires were placed. After leveling and alignment, in titanium-molybdenum and stainless steel archwires with a reverse curve of Spee were used to accentuate the anterior open bite and stabilize the dental arch. Immediately before surgery, clear buttons were attached on the labial sides of the maxillary incisors, mandibular incisors, and mandibular canines for intermaxillary fixation and intermaxillary elastics during and after orthognathic surgery. Facial and intraoral photographs and preoperative radiographs were taken immediately before surgery (Figs 5 and 6). The superimposition of the pretreatment and preoperative cephalometric radiographs is shown in Figure 7. The surgical procedure consisted of maxillary impaction, distalization, and clockwise rotation (LeFort I osteotomy) with a bilateral sagittal split mandibular osteotomy and advancement genioplasty to improve the overbite and facial profile. The surgery was planned according to the protocol suggested by Arnett and Bergman 9,10 and Lee el al, 11 which consists of dentoskeletal cephalometric analysis, a prediction tracing, and prediction surgery on mounted dental casts. American Journal of Orthodontics and Dentofacial Orthopedics April 2013 Vol 143 Issue 4 Supplement 1

6 S130 Jung, Baik, and Ahn Four weeks after surgery, the patient resumed orthodontic treatment. Ten weeks after surgery, she had a consultation for dental implant placement with a prosthodontist. The prosthodontist requested additional space for a dental implant in the mandibular left first molar area. An open coil was used in that region to gain space. Dental implant placement was performed 5 months after orthognathic surgery. All of the patient s fixed appliances were removed after 23 months of active treatment. Retention was accomplished with clear vacuum-formed retainers. Final prosthetic restoration was performed 4 weeks after debonding, and new clear retainers were inserted. The instructions to the patient included nighttime retainer use for 1 year after debonding. Fig 6. Presurgical radiographs. TREATMENT RESULTS The patient developed an attractive and confident smile after treatment. Posttreatment evaluation showed favorable dental and facial changes (Fig 8). The facial Fig 7. Presurgical cephalometric superimposition. April 2013 Vol 143 Issue 4 Supplement 1 American Journal of Orthodontics and Dentofacial Orthopedics

7 Jung, Baik, and Ahn S131 Fig 8. Posttreatment facial and intraoral photographs. Fig 9. Posttreatment study models. American Journal of Orthodontics and Dentofacial Orthopedics April 2013 Vol 143 Issue 4 Supplement 1

8 S132 Jung, Baik, and Ahn Fig 10. Posttreatment radiographs. profile and lip support were improved, and the mentalis hyperactivity was reduced. Intraorally, both arches were well aligned, the dental midline was coordinated, and normal overbite and overjet relationships were achieved. Although there was no occlusal stop in the molar region at debonding, the remaining occlusion was reasonably well settled in a bilateral Class I canine relationship (Fig 9). The posttreatment panoramic radiograph showed good overall root parallelism without evidence of root resorption (Fig 10). The condyle shape was maintained without any significant change. The posttreatment lateral cephalometric radiograph and superimposed tracing showed that the patient s maxilla was superiorly and posteriorly moved; this induced autorotation of the mandible. In addition, concurrent mandibular advancement surgery with advancement genioplasty significantly improved her facial profile and lip support (Figs 10 and 11). The posttreatment posteroanterior cephalometric radiograph showed that the asymmetry of the mandibular angle was corrected. Fig 11. Cephalometric superimposition between pretreatment and posttreatment stages. April 2013 Vol 143 Issue 4 Supplement 1 American Journal of Orthodontics and Dentofacial Orthopedics

9 Jung, Baik, and Ahn S133 Because of alveolar ridge remodeling caused by the absence of occlusal load in the maxillary molar area, transverse skeletal discrepancy, and inadequate width control caused by the absence of posterior teeth, the posterior occlusion was restored in a crossbite relationship. 12 Prosthetic appliances were placed 4 weeks after debonding. Thirteen months after debonding, the patient returned for evaluation (Figs 12-14). She discontinued the use of the retainers a few months after debonding; despite this, her occlusion remained quite stable. The facial photographs demonstrate an acceptable profile and a balanced, natural smile. Comparison of the posttreatment and postretention cephalograms showed negligible dental and skeletal changes in the maxilla and the mandible (Fig 15). DISCUSSION Skeletal anterior open bite is often seen in patients with a short ramus height, a high mandibular plane angle, and excessive anterior facial height and is frequently associated with the absence of passive lip competence. 13 Because intrusion is a more stable type of tooth movement than extrusion, many orthopedic-orthodontic methods have been used to correct open bite by intrusion or relative intrusion of the posterior teeth. 14 Although such orthodontic intrusion can often yield acceptable results, adults with open bite and mandibular deficiency frequently require orthognathic surgery for effective correction and improvement of the facial profile. 15 Furthermore, because orthodontic intrusion of the posterior teeth was impossible in this patient, orthognathic surgery was required to correct the profile and obtain a stable result. If a patient has an anterior open bite with a severely retruded chin, it becomes more difficult to determine the surgical plan. Counterclockwise rotation of the mandibular distal segment might be a good surgical option for open-bite correction and profile improvement in skeletal Class II patients. However, counterclockwise rotation of the mandible is the least stable form of mandibular surgery because it frequently stretches the soft tissues and the jaw muscles. 16 In addition, counterclockwise rotation and advancement of the mandible might increase temporomandibular joint signs and symptoms. 17 For this reason, maxillary impaction with clockwise rotation was performed to induce autorotation of the mandible, which might have significantly contributed to the posttreatment stability. Masseter muscle detachment was additionally designed to minimize the possible side effects and postoperative relapse. Mandibular advancement surgery is another considerable factor in East Asian female patients. Advancement of the mandible usually leads to a larger-appearing lower face and a more prominent mandible; this can cause a strong and masculine impression. 18 East Asian women generally desire a more delicate and feminine facial shape. This can be seen in the frequent requests for contouring the prominent mandibular angle and slight undercorrection of the Class II skeletal pattern during surgical treatment planning for Korean Class II women. 19,20 Our patient s skeletal pattern was corrected to a mild Class II skeletal relationship (ANB angle, 4.5 ). Concurrent mandibular angle reduction was also designed to minimize gonial prominence and correct the morphologic difference between the right and left angle areas. The remaining concave profile was compensated by advancement genioplasty. Temporomandibular joint disorders are characterized by intra-articular positional or structural abnormalities. A recent review study showed that the prevalence rates of temporomandibular joint disorders ranged from 16% to 59% for symptoms and from 33% to 86% for clinical signs. 21 One of the most common joint pathologies affecting the temporomandibular joint is disc displacement. Previous research showed that temporomandibular joint disc displacement can progress without clinical symptoms, 21 and that a distally inclined condylar shape is an important indicator of temporomandibular joint disc displacement. 22 This patient had a distally inclined condylar shape (Fig 3), indicating that her anterior open bite might be related to asymptomatically progressing temporomandibular joint changes. Therefore, the possibility of temporomandibular joint signs and symptoms during or after orthodontic treatment was explained to the patient before treatment, and temporomandibular joint-related signs and symptoms were carefully monitored during the entire treatment period. In addition, self-care strategies, including jaw exercises, heat packs, a soft diet, and guidance in the reduction of parafunctional activities, were used in the postoperative treatment period. 23 Fortunately, she had no temporomandibular joint signs or symptoms during or after treatment, and this stable temporomandibular joint status was the foundation of the stable treatment result. Adults often reject orthodontic treatment because of the esthetic impairment by the long-term use of fixed labial orthodontic appliances. Our patient and her employer (an international airline) asked us to treat her with invisible appliances. We could fulfill their needs using lingual orthodontic appliances and clear buttons. Occlusal and lip cants are the most noticeable features in a patient with facial asymmetry. The lip cant is determined by the difference in the height of the commissures between the left and right sides. Because bimaxillary American Journal of Orthodontics and Dentofacial Orthopedics April 2013 Vol 143 Issue 4 Supplement 1

10 S134 Jung, Baik, and Ahn Fig 12. Postretention facial and intraoral photographs. Fig 13. Postretention study models. April 2013 Vol 143 Issue 4 Supplement 1 American Journal of Orthodontics and Dentofacial Orthopedics

11 Jung, Baik, and Ahn S135 Fig 14. Postretention radiographs. Fig 15. Cephalometric superimposition between posttreatment and postretention stages. surgery cannot adjust all factors contributing to lip commissural height, the change in lip cant is usually not fully responsive to hard-tissue movement. 24 Fortunately, the patient s lip cant was almost completely corrected by the surgical cant correction (Fig 5). The asymmetric smiling in the posttreatment facial photographs (Fig 8) was due to her habit of asymmetric smiling that can be seen in the pretreatment facial photographs (Fig 1). Implants for tooth replacement have become a reliable and predictable treatment option for partially or completely edentulous patients. The survival rate of these implants is over 90% even with poor bone quality. 25 Although it is possible to successfully load a single-tooth implant immediately or soon after placement in selected patients, 26 trends suggest that immediate or early-loaded implants fail more often than do those that are conventionally loaded, especially in patients with bilateral multiple missing teeth. 27 This patient required 5 implants in the posterior region. Since the implants were placed during the finishing stages of orthodontic treatment, porcelain prosthetic devices could be placed safely 4 weeks after debonding. The patient suffered from frequent American Journal of Orthodontics and Dentofacial Orthopedics April 2013 Vol 143 Issue 4 Supplement 1

12 S136 Jung, Baik, and Ahn indigestion before orthodontic treatment, but now she reports that her condition has improved with better masticatory performance. Notwithstanding the disuse of the retainers, the patient s occlusion was still acceptable, and all restorations and the periodontium were in good condition, as seen in the postretention photographs and radiographs (Figs 12-15). The patient was pleased with the improvement in her masticatory ability. Her new balanced occlusion will help her to maintain oral and general health for the rest of her life. CONCLUSIONS The patient had a Class II canine relationship and anterior open bite without posterior occlusal contact. In addition, she showed vertical maxillary asymmetry, a hyperdivergent facial pattern, and a severely retruded chin. Fixed orthodontic treatment with invisible lingual appliances and double jaw surgery were performed to correct her malocclusion and improve her facial esthetics. The posterior occlusion was restored with dental implants after orthodontic treatment. REFERENCES 1. Mihalik CA, Proffit WR, Phillips C. Long-term follow-up of Class II adults treated with orthodontic camouflage: a comparison with orthognathic surgery outcomes. Am J Orthod Dentofacial Orthop 2003;123: Ng CS, Wong WK, H agg U. Orthodontic treatment of anterior open bite. Int J Paediatr Dent 2008;18: Watson WG. A computerized appraisal of the high-pull face-bow. Am J Orthod 1972;62: Iscan HN, Akkaya S, Koralp E. The effects of the spring-loaded posterior bite-block on the maxillo-facial morphology. Eur J Orthod 1992;14: Fr ankel R, Fr ankel C. A functional approach to treatment of skeletal open bite. Am J Orthod 1983;84: Kim YH, Han UK, Lim DD, Serraon ML. Stability of anterior openbite correctionwithmultiloopedgewisearchwiretherapy: acephalometric follow-up study. Am J Orthod Dentofacial Orthop 2000;118: Moon CH, Lee JS, Lee HS, Choi JH. Non-surgical treatment and retention of open bite in adult patients with orthodontic miniimplants. Korean J Orthod 2009;39: Proffit WR, Bailey LJ, Phillips C, Turvey TA. Long-term stability of surgical open-bite correction by LeFort I osteotomy. Angle Orthod 2000;70: Arnett GW, Bergman RT. Facial keys to orthodontic diagnosis and treatment planning part II. Am J Orthod Dentofacial Orthop 1993;103: Arnett GW, Bergman RT. Facial keys to orthodontic diagnosis and treatment planning. Part I. Am J Orthod Dentofacial Orthop 1993; 103: Lee JH, Tachibana H, Morinaga Y, Fujimura Y, Yamada K. Modulation of proliferation and differentiation of C2C12 skeletal muscle cells by fatty acids. Life Sci 2009;84: Sanghvi SJ, Bhatt NA, Bhargava K. An evaluation of cross-bite ridge relationships. A study of articulated jaw records of 150 edentulous patients. J Prosthet Dent 1981;45: Kuroda S, Katayama A, Takano-Yamamoto T. Severe anterior open-bite case treated using titanium screw anchorage. Angle Orthod 2004;74: Park YC, Lee HA, Choi NC, Kim DH. Open bite correction by intrusion of posterior teeth with miniscrews. Angle Orthod 2008;78: Greenlee GM, Huang GJ, Chen SS, Chen J, Koepsell T, Hujoel P. Stability of treatment for anterior open-bite malocclusion: a meta-analysis. Am J Orthod Dentofacial Orthop 2011;139: Wolford LM, Chemello PD, Hilliard FW. Occlusal plane alteration in orthognathic surgery. J Oral Maxillofac Surg 1993;51: Frey DR, Hatch JP, Van Sickels JE, Dolce C, Rugh JD. Effects of surgical mandibular advancement and rotation on signs and symptoms of temporomandibular disorder: a 2-year follow-up study. Am J Orthod Dentofacial Orthop 2008;133: 490.e Oland J, Jensen J, Papadopoulos MA, Melsen B. Does skeletal facial profile influence preoperative motives and postoperative satisfaction? A prospective study of 66 surgical-orthodontic patients. J Oral Maxillofac Surg 2011;69: Baek SM, Baek RM, Shin MS. Refinement in aesthetic contouring of the prominent mandibular angle. Aesthetic Plast Surg 1994; 18: Jung MH. Class II treatment with 2 jaw surgery. J Korean Found Gnatho Res 2011;10: Tanaka E, Detamore MS, Mercuri LG. Degenerative disorders of the temporomandibular joint: etiology, diagnosis, and treatment. J Dent Res 2008;87: Ahn SJ, Kim TW, Lee DY, Nahm DS. Evaluation of internal derangement of the temporomandibular joint by panoramic radiographs compared with magnetic resonance imaging. Am J Orthod Dentofacial Orthop 2006;129: Burgess JA, Sommers EE, Truelove EL, Dworkin SF. Short-term effect of two therapeutic methods on myofascial pain and dysfunction of the masticatory system. J Prosthet Dent 1988;60: Kim YH, Jeon J, Rhee JT, Hong J. Change of lip cant after bimaxillary orthognathic surgery. J Oral Maxillofac Surg 2010;68: Pjetursson BE, Tan WC, Zwahlen M, Lang NP. A systematic review of the success of sinus floor elevation and survival of implants inserted in combination with sinus floor elevation. J Clin Periodontol 2008;35: Atieh MA, Payne AG, Duncan WJ, de Silva RK, Cullinan MP. Immediate placement or immediate restoration/loading of single implants for molar tooth replacement: a systematic review and meta-analysis. Int J Oral Maxillofac Implants 2010;25: Esposito M, Grusovin MG, Coulthard P, Worthington HV. Different loading strategies of dental implants: a Cochrane systematic review of randomised controlled clinical trials. Eur J Oral Implantol 2008;1: April 2013 Vol 143 Issue 4 Supplement 1 American Journal of Orthodontics and Dentofacial Orthopedics