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Orthodontic traction in a patient with cleidocranial dysplasia: 3 years of follow-up
CASE REPORT
Orthodontic traction in a patient with cleidocranial dysplasia: 3 years of follow-up Roberto Rocha,a Manuela Batistella Zasso,b Gilberto Floriano,b Carla Derech,c Gerson Ulema Ribeiro,a Arno Locks,c and Daltro Ritterc Florianopolis, Santa Catarina, Brazil This case report describes the treatment and long-term follow-up care of a patient diagnosed with cleidocranial dysplasia who had multiple impacted permanent and supernumerary teeth. The aim of the treatment was to provide an adequate esthetic and functional reconstruction of the occlusion with good periodontal care. The patient was treated with a multidisciplinary therapeutic protocol including orthodontic and surgical procedures, and traction of 11 permanent teeth. The proposed objectives of good occlusion, normal function, healthy periodontium, and balanced profile were achieved, and the 3-year follow-up records showed stable results. (Am J Orthod Dentofacial Orthop 2014;146:108-18)
C
leidocranial dysplasia (CCD) is a rare congenital bone disorder with an autosomal dominant pattern of inheritance, but approximately 40% of patients appear to have spontaneous mutations that affect both sexes to an equal extent.1,2 The prevalence is 1 in a million, with complete penetrance and widely variable expressivity.3 Clavicle hypoplasia results in placement of the shoulders close to the front of the body, and these patients often seem to have a long neck.4 The sagittal fontanelle suture is characteristically sunken, giving the skull a flattened appearance. The frontal, parietal, and occipital bones are also prominent, and the sinuses are underdeveloped and narrow. The face is brachycephalic with an increased transverse diameter of the skull.5 The eyes are widely spaced, and the base of the nose is depressed and wide.6 In addition, midfacial hypoplasia, which is most likely related to the shortened anterior cranial base, and a relatively prognathic mandible are craniofacial anomalies frequently associated with the condition. Patients also have reduced height of the lower third of the face and a skeletal Class III
From the Federal University of Santa Catarina, Florian opolis, Santa Catarina, Brazil. a Adjunct professor, Department of Dentistry. b Postgraduate student, Department of Orthodontics. c Professor, Department of Orthodontics. All authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest, and none were reported. Address correspondence to: Manuela Batistella Zasso, 925, Lauro Linhares, St Apt 304, Trindade, Florianopolis, Santa Catarina, Brazil 88036001; e-mail, [email protected]. Submitted, June 2013; revised and accepted, September 2013. 0889-5406/$36.00 Copyright Ó 2014 by the American Association of Orthodontists. http://dx.doi.org/10.1016/j.ajodo.2013.09.016
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tendency because of the underdeveloped maxilla and the upward and forward mandibular rotation.5,7 The oral findings usually identified in patients with CCD are retained deciduous teeth without root resorption and supernumerary teeth that displace the developing permanent teeth and obstruct their eruption, resulting in multiple impacted permanent teeth and a serious malocclusion. The vertical development of the alveolar bone is reduced; there is a late but spontaneous eruption of the permanent first and, usually, the second molars in both jaws, and there is a delay of approximately 3 years in the root development of the permanent teeth.4,5,7 The teeth often have hypoplastic enamel and dilacerated roots without cellular cementum.8 Some tooth germs are deformed and rudimentary, and microdontia and twinning are also present.4 The treatment of patients with CCD requiring traction of many teeth is a challenge because there is no extensive literature about the subject, making it difficult to follow a protocol of how to perform the traction, especially when the patient is an adult. In this case report, special emphasis has been given to potential dental complications and their management. DIAGNOSIS AND ETIOLOGY
A woman, 22 years 8 months of age, sought dental treatment at the Department of Dentistry of the Federal University of Santa Catarina in Brazil and was diagnosed with CCD. The facial analysis showed midfacial hypoplasia with poor maxillary growth in the anteroposterior direction. The intrabuccal assessment showed the permanent dentition, with the mandibular midline deviated 3 mm to the left and the maxillary midline deviated 1
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Fig 1. Pretreatment facial and intraoral photographs at age 22 years 8 months.
mm to the right (Fig 1). The patient had 8 erupted permanent teeth in the maxillary arch and only 5 in the mandibular arch (Fig 2). The panoramic radiograph (Fig 3) showed the retained permanent teeth, 3 supernumerary teeth in the mandible, agenesis of the maxillary right second premolar, as well as some dilacerated roots. A radiolucency was observed in the periapical region of the mandibular right premolar tooth, but because there was no pain and the teeth were vital, it was determined to be insignificant. This was also visible in the posttreatment panoramic image, where only a variation in bone pattern was diagnosed, since the adjacent teeth were healthy, and the lamina dura was integrated. The cephalometric radiograph (Fig 3) showed a skeletal Class III pattern caused by forward mandibular rotation with a predominantly horizontal facial growth vector (ANB, 0 ; GoGn-SN, 24 ; FMA, 20 ). The Wits appraisal markedly showed the Class III pattern between the maxilla and the mandible. The incisors were
retroclined, especially the mandibular ones (1.NA, 21 ; 1-NA, 3 mm; 1.NB, 18 ; 1-NB, 2 mm; IMPA, 85 ; Table). TREATMENT OBJECTIVES
The following treatment objectives were established: (1) clear the path of eruption of the submerged permanent teeth by extraction of the supernumerary teeth; (2) proceed with forced eruption of the permanent teeth with orthodontic traction; and (3) correct the anterior and posterior crossbite and perform dental alignment and leveling to achieve adequate intercuspation. Thus, the main objectives of the treatment for this patient were to create a stable functional occlusion. A balanced profile was also desired. TREATMENT ALTERNATIVES
The aim of dental management of patients with CCD is to achieve an optimal functional and cosmetic result
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Fig 2. Pretreatment study models.
by early adulthood.7 Unfortunately, this patient received assistance only after she had already reached adulthood, so we had the following alternatives with a multidisciplinary approach. 1.
2.
3.
4.
Extraction of all unerupted teeth, followed by orthodontic alignment and leveling of the erupted teeth in preparation for a partial dental prostheses.9 Surgical exposure of the unerupted teeth to provide support for an overdenture.10 The overdenture could also be supported by implants.11 This option also included orthodontic alignment and leveling of the erupted teeth. Removal of the supernumerary teeth, surgical exposure of the impacted teeth, and then their orthodontic traction. First, traction of the unerupted mandibular teeth would occur, supported by a removable appliance in the maxillary arch. When possible, the fixed orthodontic appliance would be applied in the mandibular arch for tooth alignment and, subsequently, traction of the unerupted maxillary teeth. Removal of the supernumerary teeth, surgical exposure of the impacted teeth, and orthodontic traction of the unerupted mandibular and maxillary teeth, supported by skeletal anchorage. Then, when all
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teeth were erupted in sequence, conventional orthodontic treatment would begin. TREATMENT PROGRESS
Initially, the supernumerary teeth were extracted. The next step was surgical exposure of the unerupted mandibular teeth. The orthodontic attachments were bonded for traction supported by a maxillary removable appliance. In all forced eruptions, intraoral elastics were applied with a force varying from 50 to 150 g; these were used throughout the day as frequently as possible. Next, edgewise brackets were bonded in the mandibular arch, and we proceeded with alignment and leveling. Once the mandibular teeth were aligned, the patient was referred again to the oral surgeon for exposure of the unerupted maxillary teeth and the bond attachments in the maxillary teeth to support the intraoral elastics and provide traction. Some teeth were erupted with force. When the patient reached the age of 28 years, the complete fixed appliances were installed. Expanded arches were used to create space in the arch and slightly project the maxillary anterior teeth. During this phase, the goals were alignment and leveling, anterior and posterior crossbite correction, and improvement of the incisor relationships. The
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The mechanics of Class II elastics on the left and Class III elastics on the right were used to correct the midline with a force of 150 g as frequently as possible throughout the day. TREATMENT RESULTS
Fig 3. Pretreatment cephalometric and panoramic radiographs.
Table. Cephalometric measurements Measurement Pretreatment Posttreatment Follow-up Skeletal pattern SNA ( ) 89 89 88 89 89 88 SNB ( ) ANB ( ) 0 0 0 Facial convexity ( ) 0 1 2 57 57 58 Y-axis ( ) Facial angle ( ) 94 92 92 SN.GoGn ( ) 24 23 23 FMA ( ) 20 19 19 AO-BO (mm) 4 3 2 Dental pattern IMPA ( ) 85 92 92 1-NA (mm) 3 6 5 1.NA ( ) 21 30 29 1-NB (mm) 2 3 3 1.NB ( ) 18 23 23 1.1 ( ) 140 125 127 Profile Upper lip-S line (mm) 2 3 3 Lower lip-S-line (mm) 0 2 2
mechanics of the segmented arch with cantilevers were used to assist in tooth traction, and continuous arches with loops were used for leveling and space closure.
At 35 years 10 months of age, this patient's expected orthodontic outcomes had been achieved; thus, the active phase of orthodontic treatment was concluded, and the fixed appliances were debonded. Her face acquired more proportional facial thirds. The vertical dimension was restored, and the appearance of premature aging was reduced (Fig 4). The forced eruptions were performed successfully, and the teeth were well positioned. The orthodontic treatment was completed with a Class I canine occlusion and a Class II molar occlusion, with a superior midline deviation of 0.5 mm to the right, and ideal overbite and overjet (Fig 5). In addition, a removable retainer was installed in the maxillary arch, and a mandibular lingual bonded retainer was subsequently placed. The posttreatment dental casts showed good intercuspation. Because of the prolonged treatment time, the fixed appliance was removed with a crossbite between the maxillary and mandibular left first molars. When the patient returned for a checkup, it was recommended that she wear intermaxillary elastics to correct the crossbite. Two buttons were subsequently installed: 1 on the palatal face of the maxillary left first molar, and the other on the buccal face of the mandibular left first molar. The patient used the elastics for 4 months, and the bite was corrected. The final panoramic radiograph showed that no root resorption had occurred during the treatment, and the positions of the roots were satisfactory (Fig 6). The maxillomandibular relationships at the end of the treatment maintained their balance (ANB, 0 ; GoGn.SN, 23 ; FMA, 19 ; Table). Initially, the incisors were retroclined because of the absence of the canines and the lateral incisors. The inclination of the maxillary incisors subsequently changed from 21 to 29 (1.NA), and the mandibular incisors changed from 18 to 23 (1.NB) after treatment, providing better esthetics of the smile and an appropriate relationship between the incisors. The pretreatment and posttreatment cephalometric superimposition showed maintenance of the skeletal profile, since the patient had no more growth and adequate incisor repositioning (Fig 7). At 3 years posttreatment, the orthodontic results were relatively stable (Figs 8 and 9). The posttreatment periodontal examination involved measurements of sulcus depth, bleeding on probing, and visible plaque. The tests showed an overall good periodontal condition, despite some bleeding on probing
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Fig 4. Posttreatment facial and intraoral photographs at age 35 years 10 months.
and visible plaque (Fig 10). Periodontal probing showed shallow sulcus depths in some teeth and resulted in light bleeding mainly on the palatal surfaces of the mandibular teeth. Likewise, no attachment loss in the form of gingival recession was evident, depicting an excellent periodontal status. DISCUSSION
The planning of dental objectives for a patient with CCD primarily depends on the patient's needs, age at diagnosis, and social and economic circumstances. Because of technical and financial difficulties, this patient started orthodontic treatment at age 23 years, so from adolescence to young adulthood, she had serious functional and psychological problems related to her oral health and poor esthetics. The best-known orthodontic-surgical regimens are the Toronto-Melbourne6,12 and the Jerusalem approaches.7,13 Regardless of the patient's conditions and the protocol to be followed, the aim of dental management in a patient with CCD is to achieve, when
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possible, an optimal functional and cosmetic result by early adulthood. The Toronto-Melbourne approach is based on timed, serial extractions of deciduous teeth; it depends on the extent to which the roots of the permanent teeth have developed, so for this approach, the best period for treatment is in the early stages with a combined oral surgery and orthodontic approach. It is recommended that surgical procedures should begin about 5 to 6 years of age with extraction of the anterior deciduous teeth. Later (6 or 7 years of age), the deciduous incisors are exposed, and healing is allowed; orthodontic brackets are placed on the permanent incisors as soon as possible; and the deciduous posterior teeth are extracted. When the patient is 9 or 10 years of age, the permanent premolars are exposed and allowed to heal. Thereafter, orthodontic brackets are placed on the permanent canines and premolars. During each procedure, which is performed under general anesthesia, the supernumerary teeth are also removed together with the bone covering the underlying permanent teeth.6,12
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Fig 5. Posttreatment study models.
The Jerusalem approach is based on at least 2 surgical interventions, depending on the root development of the permanent dentition. In the first phase, which begins at approximately 10 to 12 years of age, the anterior deciduous teeth and all supernumerary teeth are extracted. In addition, the permanent incisors are exposed, and orthodontic attachments are placed for traction. In phase 2 (age 13 years and older), the posterior deciduous teeth are extracted, the unerupted permanent canines and premolars are exposed, and orthodontic attachments are bonded. At first, according to the Toronto-Melbourne protocol, there would be no need for tooth traction. Therefore, the procedure must begin early in life, and the expectation is that only the removal of bone overlying the permanent teeth with developing roots is sufficient for tooth eruption. In the Jerusalem approach, which begins later in life, traction of the permanent teeth is certainly part of the proposal. In any case, these procedures are all undertaken over a long period. Patient compliance is essential for a favorable outcome for any modality. Starting early with so many surgical procedures can be challenging for a young child but offers the advantage that the patient will have restored function and esthetics in adolescence, which can be psychologically important.
Our patient sought treatment when she was 22 years old, so it was not possible to extract the teeth because of their radicular development. Traction of all unerupted teeth was not possible for this patient, although it was necessary. Another option was extraction of all unerupted teeth and installation of a dental prosthesis or dental implants. This would restore function and esthetics, but the erupted teeth would still require orthodontic alignment. This would have shortened the treatment time, but the patient refused extraction of all unerupted teeth. Her choice was traction of the unerupted teeth, regardless of treatment duration. The orthodontic treatment lasted about 13 years. This seems like a long time, but it is a reasonable time for a patient with CCD. Initially, the barriers (supernumerary and deciduous teeth) were surgically removed, and the first orthodontic challenge was selecting which anchorage to use for traction. It has been suggested that a palatal arch is a better anchor, but not using erupted teeth as anchorage was preferred because the time for traction would be long and the supporting tissues of the teeth could be damaged.13 The initial panoramic view (Fig 3) shows the right permanent first molar with incipient bone
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Fig 7. Pretreatment (black) and posttreatment (red) cephalometric tracings, superimposed on the sellanasion line at sella.
Fig 6. Posttreatment cephalometric and panoramic radiographs.
loss in the mesial face and root canal treatment and extensive coronal restoration of the left permanent first molar, so these were not considered anchors by themselves throughout the traction process. Among the treatment alternatives presented in this case report, one suggests the use of skeletal anchorage to support the traction of all teeth. Skeletal anchorage in orthodontics as absolute anchorage provides new opportunities to guide impacted teeth into occlusion and to treat patients with CCD, making it possible to induce eruption simultaneously of the maxillary and mandibular teeth and consequently reducing patients' treatment times and psychological stress.14 Skeletal anchorage would be the best option for treatment, but when the planning was completed for our patient, conditions for skeletal anchorage were not favorable, so another alternative had to be selected. The option for treatment was the use of a dentomucoperiosteal-supported removable acrylic plate, first in the maxillary arch, because there were not sufficient teeth in the mandibular arch to support a removable plate. As a result, the first teeth to be tractioned were the mandibular ones. If traction supported by skeletal anchorage had been performed, the
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treatment time would have been much shorter. Even without using skeletal anchorage, the result was satisfactory because of the excellent cooperation of the patient, who used the intraoral elastics properly. Some authors have suggested that early surgical management with serial uncovering of the permanent teeth is the best choice.15 Hitchin and Fairley10 believed that the lack of eruption in patients with CCD is due to failure of resorption of the overlying alveolar bone. When these teeth are uncovered, they show a normal eruption pattern. There can also be mechanical interference from impacted supernumerary teeth.15 Still, regarding the causal effect of impacted teeth, there is no statistically significant difference between the amount of either cellular or acellular cementum covering the roots in the patient with CCD and the roots of the control teeth. So the presumption that a lack of cellular cementum causes unerupted teeth is not true.16 Regardless of the cause, it is necessary to stimulate the eruption of unerupted teeth or to force their eruption. Current treatment protocols seem to agree that treatment should begin early, and natural eruption of teeth with roots should be allowed after the removal of obstacles, such as deciduous or supernumerary teeth. In our patient, forced eruption was the only option because all roots were formed. The result was a good bone level at the end of treatment. The patient's periodontal chart (Fig 10) and her initial and final panoramic radiographs showed our follow-up of bone levels in the
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Fig 8. Long-term stability at the 3-year follow-up, with maintenance of adequate overbite and overjet.
teeth that were induced, with an ideal height of crestal bone. During the periodontal examination, the patient had slight bleeding mainly in the lingual aspects of the incisors and the first and second molars, caused by inflammation from plaque. She was instructed again to improve hygiene in these locations. The molar showed a slight bone loss that could not be attributed to the traction of the other teeth. All induced teeth showed excellent periodontal conditions at the follow-up (Fig 10). Some factors contributed to this favorable outcome, including the patient's cooperation regarding her oral hygiene and the use of extrusive forces that were compatible with a good periodontal response. Another factor was that the teeth were positioned on the route of eruption. Since the angle between the orientation of the traction and the central axis of the impacted tooth was smaller, there were more advantages to the eruption of the impacted tooth.17 It is important that the forces be directed to the lingual aspect, never
to the vestibular aspect.18 Another factor to consider was the concern over the bonding technique to allow access to the tooth for induction of eruption; this was done with minimal removal of bone tissue covering the impacted tooth crown for bonding by the closederuption technique. The literature reports a slight loss of attachment around teeth treated by the closed-eruption surgical technique and a mean increase in probing depth, but its magnitude lacks clinical significance.19 The closederuption technique is believed by some to be the best method for uncovering impacted teeth,18,19 and more periodontal and esthetic disadvantages can be expected with the apically positioned flap technique than with the closed-eruption technique.20 When impacted teeth are treated with open surgical exposure, natural eruption and orthodontic alignment have minimal effects on the periodontium, but if necessary an orthodontically induced eruption should be done.21
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Fig 9. Study models 3 years after treatment.
Fig 10. Periodontal chart showing the status at the 3-year follow-up.
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Some peculiarities are seen in the cephalometric measurements of a patient with CCD. Because the base of the skull is smaller than in patients who do not have the syndrome, measurements such as SNA, SNB, and facial angles appear greatly increased compared with normal ones.22 In addition, CCD is usually seen in a brachycephalic patient with horizontal growth, expressed by diminished measurements such as the yaxis, FMA, and SN.GoGn. The patient has these features and shows a restricted pattern of the ANB angle. Because of the shortening of the skull base, the ANB angle is not compatible with the standard skeletal measurements. Thus, the AO-BO, which evaluates the difference between the bone bases without involvement of the skull base, shows the higher values of a Class III malocclusion. Most protocols recommend a LeFort I osteotomy for the correction of skeletal discrepancies; this would have been beneficial to our patient. However, this was not possible because the clinic where she was seen at the time lacked the technical conditions for this procedure. Moreover, she had an acceptable profile before treatment, but the concavity of the profile became more evident, which precluded the standard Class III phases of posttreatment and follow up (Figs 4 and 8). The facial convexity angle also caused the increased concavity of the profile (Table). In this case, jaw advancement surgery would be recommended. Since a patient with CCD has many impacted teeth, the best way to find them is with cone-beam computed tomography, which would give greater predictability to the closed-eruption technique of surgery. Unfortunately, cone-beam computed tomography was not routinely used for localization of impacted teeth when this patient's treatment began. Thus, the method used for uncovering these impacted teeth was only conventional radiographic analysis. The surgical and orthodontic techniques involved in the dental management of this condition are demanding at the levels of diagnosis, treatment planning, and clinical management. Thus, to achieve the best possible result, the highest degrees of orthodontic and surgical cooperation are necessary.12 The orthodontic treatment can be lengthy; this patient was in treatment for approximately 13 years, so it was important to monitor and maintain excellent oral hygiene to keep her dentition healthy. CONCLUSIONS
This case report described a patient with CCD with 11 permanent and supernumerary teeth; she was
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treated by exposure and traction of the viable teeth. The success of the treatment depended on planning and patient cooperation. The treatment provided an ideal occlusion, with satisfactory periodontal results and oral esthetics, and returned important functions to her overall health and social life. Moreover, this approach provided good stability 3 years after the end of treatment. REFERENCES 1. Damm DD, Bouquot JE, Neville BW, Allen C. Oral and maxillofacial pathology. 2nd ed. Philadelphia: Saunders Elsevier; 2008. 2. Farronato G, Maspero C, Farronato D, Gioventu S. Orthodontic treatment in a patient with cleidocranial dysostosis. Angle Orthod 2009;79:178-85. 3. Mundlos S. Cleidocranial dysplasia: clinical and molecular genetics. J Med Genet 1999;36:177-82. 4. Suba Z, Balaton G, Gyulai-Gaal S, Balaton P, Barabas J, Tarjan I. Cleidocranial dysplasia: diagnostic criteria and combined treatment. J Craniofac Surg 2005;16:1122-6. 5. Shafer W, Hine M, Levy B. Shafer's textbook of oral pathology. Delhi, India: Elsevier; 2009. 6. Smylski PT, Woodside DG, Harnett BE. Surgical and orthodontic treatment of cleidocranial dysostosis. Int J Oral Surg 1974;3: 380-5. 7. Becker A, Lustmann J, Shteyer A. Cleidocranial dysplasia: part 1—general principles of the orthodontic and surgical treatment modality. Am J Orthod Dentofacial Orthop 1997;111: 28-33. 8. Nebgen D, Wood RS, Shapiro RD. Management of a mandibular fracture in a patient with cleidocranial dysplasia: report of a case and review of the literature. J Oral Maxillofac Surg 1991; 49:405-9. 9. Winther JE, Khan MW. Cleidocranial dysostosis: report of 4 cases. Dent Pract Dent Rec 1972;22:215-9. 10. Hitchin AD, Fairley JM. Dental management in cleido-cranial dysostosis. Br J Oral Surg 1974;12:46-55. 11. Becktor KB, Becktor JP, Keller EE. Growth analysis of a patient with ectodermal dysplasia treated with endosseous implants: a case report. Int J Oral Maxillofac Implants 2001; 16:864-74. 12. Hall RK, Hyland AL. Combined surgical and orthodontic management of the oral abnormalities in children with cleidocranial dysplasia. Int J Oral Surg 1978;7:267-73. 13. Becker A, Shteyer A, Bimstein E, Lustmann J. Cleidocranial dysplasia: part 2—treatment protocol for the orthodontic and surgical modality. Am J Orthod Dentofacial Orthop 1997;111: 173-83. 14. Kuroda S, Yanagita T, Kyung HM, Takano-Yamamoto T. Titanium screw anchorage for traction of many impacted teeth in a patient with cleidocranial dysplasia. Am J Orthod Dentofacial Orthop 2007;131:666-9. 15. Farrar EL, Van Sickels JE. Early surgical management of cleidocranial dysplasia: a preliminary report. J Oral Maxillofac Surg 1983; 41:527-9. 16. Counts AL, Rohrer MD, Prasad H, Bolen P. An assessment of root cementum in cleidocranial dysplasia. Angle Orthod 2001;71: 293-8. 17. Zhang J, Wang XX, Ma SL, Ru J, Ren XS. 3-dimensional finite element analysis of periodontal stress distribution when
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impacted teeth are tracted. Hua Xi Kou Qiang Yi Xue Za Zhi 2008;26:19-22. 18. Rizzatto SM, Menezes LM, Allgayer S, Batista EL Jr, Freitas MP, Loro RC. Orthodontically induced eruption of a horizontally impacted maxillary central incisor. Am J Orthod Dentofacial Orthop 2013;144:119-29. 19. Becker A, Brin I, Ben-Bassat Y, Zilberman Y, Chaushu S. Closederuption surgical technique for impacted maxillary incisors: a postorthodontic periodontal evaluation. Am J Orthod Dentofacial Orthop 2002;122:9-14.
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20. Vermette ME, Kokich VG, Kennedy DB. Uncovering labially impacted teeth: apically positioned flap and closed-eruption techniques. Angle Orthod 1995;65:23-32. 21. Schmidt AD, Kokich VG. Periodontal response to early uncovering, autonomous eruption, and orthodontic alignment of palatally impacted maxillary canines. Am J Orthod Dentofacial Orthop 2007;131:449-55. 22. Kreiborg S, Jensen BL, Bjork A, Skieller V. Abnormalities of the cranial base in cleidocranial dysostosis. Am J Orthod 1981;79: 549-57.
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Orthodontic traction in a patient with cleidocranial dysplasia: 3 years of follow-up Roberto Rocha,a Manuela Batistella Zasso,b Gilberto Floriano,b Carla Derech,c Gerson Ulema Ribeiro,a Arno Locks,c and Daltro Ritterc Florianopolis, Santa Catarina, Brazil This case report describes the treatment and long-term follow-up care of a patient diagnosed with cleidocranial dysplasia who had multiple impacted permanent and supernumerary teeth. The aim of the treatment was to provide an adequate esthetic and functional reconstruction of the occlusion with good periodontal care. The patient was treated with a multidisciplinary therapeutic protocol including orthodontic and surgical procedures, and traction of 11 permanent teeth. The proposed objectives of good occlusion, normal function, healthy periodontium, and balanced profile were achieved, and the 3-year follow-up records showed stable results. (Am J Orthod Dentofacial Orthop 2014;146:108-18)
C
leidocranial dysplasia (CCD) is a rare congenital bone disorder with an autosomal dominant pattern of inheritance, but approximately 40% of patients appear to have spontaneous mutations that affect both sexes to an equal extent.1,2 The prevalence is 1 in a million, with complete penetrance and widely variable expressivity.3 Clavicle hypoplasia results in placement of the shoulders close to the front of the body, and these patients often seem to have a long neck.4 The sagittal fontanelle suture is characteristically sunken, giving the skull a flattened appearance. The frontal, parietal, and occipital bones are also prominent, and the sinuses are underdeveloped and narrow. The face is brachycephalic with an increased transverse diameter of the skull.5 The eyes are widely spaced, and the base of the nose is depressed and wide.6 In addition, midfacial hypoplasia, which is most likely related to the shortened anterior cranial base, and a relatively prognathic mandible are craniofacial anomalies frequently associated with the condition. Patients also have reduced height of the lower third of the face and a skeletal Class III
From the Federal University of Santa Catarina, Florian opolis, Santa Catarina, Brazil. a Adjunct professor, Department of Dentistry. b Postgraduate student, Department of Orthodontics. c Professor, Department of Orthodontics. All authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest, and none were reported. Address correspondence to: Manuela Batistella Zasso, 925, Lauro Linhares, St Apt 304, Trindade, Florianopolis, Santa Catarina, Brazil 88036001; e-mail, [email protected]. Submitted, June 2013; revised and accepted, September 2013. 0889-5406/$36.00 Copyright Ó 2014 by the American Association of Orthodontists. http://dx.doi.org/10.1016/j.ajodo.2013.09.016
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tendency because of the underdeveloped maxilla and the upward and forward mandibular rotation.5,7 The oral findings usually identified in patients with CCD are retained deciduous teeth without root resorption and supernumerary teeth that displace the developing permanent teeth and obstruct their eruption, resulting in multiple impacted permanent teeth and a serious malocclusion. The vertical development of the alveolar bone is reduced; there is a late but spontaneous eruption of the permanent first and, usually, the second molars in both jaws, and there is a delay of approximately 3 years in the root development of the permanent teeth.4,5,7 The teeth often have hypoplastic enamel and dilacerated roots without cellular cementum.8 Some tooth germs are deformed and rudimentary, and microdontia and twinning are also present.4 The treatment of patients with CCD requiring traction of many teeth is a challenge because there is no extensive literature about the subject, making it difficult to follow a protocol of how to perform the traction, especially when the patient is an adult. In this case report, special emphasis has been given to potential dental complications and their management. DIAGNOSIS AND ETIOLOGY
A woman, 22 years 8 months of age, sought dental treatment at the Department of Dentistry of the Federal University of Santa Catarina in Brazil and was diagnosed with CCD. The facial analysis showed midfacial hypoplasia with poor maxillary growth in the anteroposterior direction. The intrabuccal assessment showed the permanent dentition, with the mandibular midline deviated 3 mm to the left and the maxillary midline deviated 1
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Fig 1. Pretreatment facial and intraoral photographs at age 22 years 8 months.
mm to the right (Fig 1). The patient had 8 erupted permanent teeth in the maxillary arch and only 5 in the mandibular arch (Fig 2). The panoramic radiograph (Fig 3) showed the retained permanent teeth, 3 supernumerary teeth in the mandible, agenesis of the maxillary right second premolar, as well as some dilacerated roots. A radiolucency was observed in the periapical region of the mandibular right premolar tooth, but because there was no pain and the teeth were vital, it was determined to be insignificant. This was also visible in the posttreatment panoramic image, where only a variation in bone pattern was diagnosed, since the adjacent teeth were healthy, and the lamina dura was integrated. The cephalometric radiograph (Fig 3) showed a skeletal Class III pattern caused by forward mandibular rotation with a predominantly horizontal facial growth vector (ANB, 0 ; GoGn-SN, 24 ; FMA, 20 ). The Wits appraisal markedly showed the Class III pattern between the maxilla and the mandible. The incisors were
retroclined, especially the mandibular ones (1.NA, 21 ; 1-NA, 3 mm; 1.NB, 18 ; 1-NB, 2 mm; IMPA, 85 ; Table). TREATMENT OBJECTIVES
The following treatment objectives were established: (1) clear the path of eruption of the submerged permanent teeth by extraction of the supernumerary teeth; (2) proceed with forced eruption of the permanent teeth with orthodontic traction; and (3) correct the anterior and posterior crossbite and perform dental alignment and leveling to achieve adequate intercuspation. Thus, the main objectives of the treatment for this patient were to create a stable functional occlusion. A balanced profile was also desired. TREATMENT ALTERNATIVES
The aim of dental management of patients with CCD is to achieve an optimal functional and cosmetic result
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Fig 2. Pretreatment study models.
by early adulthood.7 Unfortunately, this patient received assistance only after she had already reached adulthood, so we had the following alternatives with a multidisciplinary approach. 1.
2.
3.
4.
Extraction of all unerupted teeth, followed by orthodontic alignment and leveling of the erupted teeth in preparation for a partial dental prostheses.9 Surgical exposure of the unerupted teeth to provide support for an overdenture.10 The overdenture could also be supported by implants.11 This option also included orthodontic alignment and leveling of the erupted teeth. Removal of the supernumerary teeth, surgical exposure of the impacted teeth, and then their orthodontic traction. First, traction of the unerupted mandibular teeth would occur, supported by a removable appliance in the maxillary arch. When possible, the fixed orthodontic appliance would be applied in the mandibular arch for tooth alignment and, subsequently, traction of the unerupted maxillary teeth. Removal of the supernumerary teeth, surgical exposure of the impacted teeth, and orthodontic traction of the unerupted mandibular and maxillary teeth, supported by skeletal anchorage. Then, when all
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teeth were erupted in sequence, conventional orthodontic treatment would begin. TREATMENT PROGRESS
Initially, the supernumerary teeth were extracted. The next step was surgical exposure of the unerupted mandibular teeth. The orthodontic attachments were bonded for traction supported by a maxillary removable appliance. In all forced eruptions, intraoral elastics were applied with a force varying from 50 to 150 g; these were used throughout the day as frequently as possible. Next, edgewise brackets were bonded in the mandibular arch, and we proceeded with alignment and leveling. Once the mandibular teeth were aligned, the patient was referred again to the oral surgeon for exposure of the unerupted maxillary teeth and the bond attachments in the maxillary teeth to support the intraoral elastics and provide traction. Some teeth were erupted with force. When the patient reached the age of 28 years, the complete fixed appliances were installed. Expanded arches were used to create space in the arch and slightly project the maxillary anterior teeth. During this phase, the goals were alignment and leveling, anterior and posterior crossbite correction, and improvement of the incisor relationships. The
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The mechanics of Class II elastics on the left and Class III elastics on the right were used to correct the midline with a force of 150 g as frequently as possible throughout the day. TREATMENT RESULTS
Fig 3. Pretreatment cephalometric and panoramic radiographs.
Table. Cephalometric measurements Measurement Pretreatment Posttreatment Follow-up Skeletal pattern SNA ( ) 89 89 88 89 89 88 SNB ( ) ANB ( ) 0 0 0 Facial convexity ( ) 0 1 2 57 57 58 Y-axis ( ) Facial angle ( ) 94 92 92 SN.GoGn ( ) 24 23 23 FMA ( ) 20 19 19 AO-BO (mm) 4 3 2 Dental pattern IMPA ( ) 85 92 92 1-NA (mm) 3 6 5 1.NA ( ) 21 30 29 1-NB (mm) 2 3 3 1.NB ( ) 18 23 23 1.1 ( ) 140 125 127 Profile Upper lip-S line (mm) 2 3 3 Lower lip-S-line (mm) 0 2 2
mechanics of the segmented arch with cantilevers were used to assist in tooth traction, and continuous arches with loops were used for leveling and space closure.
At 35 years 10 months of age, this patient's expected orthodontic outcomes had been achieved; thus, the active phase of orthodontic treatment was concluded, and the fixed appliances were debonded. Her face acquired more proportional facial thirds. The vertical dimension was restored, and the appearance of premature aging was reduced (Fig 4). The forced eruptions were performed successfully, and the teeth were well positioned. The orthodontic treatment was completed with a Class I canine occlusion and a Class II molar occlusion, with a superior midline deviation of 0.5 mm to the right, and ideal overbite and overjet (Fig 5). In addition, a removable retainer was installed in the maxillary arch, and a mandibular lingual bonded retainer was subsequently placed. The posttreatment dental casts showed good intercuspation. Because of the prolonged treatment time, the fixed appliance was removed with a crossbite between the maxillary and mandibular left first molars. When the patient returned for a checkup, it was recommended that she wear intermaxillary elastics to correct the crossbite. Two buttons were subsequently installed: 1 on the palatal face of the maxillary left first molar, and the other on the buccal face of the mandibular left first molar. The patient used the elastics for 4 months, and the bite was corrected. The final panoramic radiograph showed that no root resorption had occurred during the treatment, and the positions of the roots were satisfactory (Fig 6). The maxillomandibular relationships at the end of the treatment maintained their balance (ANB, 0 ; GoGn.SN, 23 ; FMA, 19 ; Table). Initially, the incisors were retroclined because of the absence of the canines and the lateral incisors. The inclination of the maxillary incisors subsequently changed from 21 to 29 (1.NA), and the mandibular incisors changed from 18 to 23 (1.NB) after treatment, providing better esthetics of the smile and an appropriate relationship between the incisors. The pretreatment and posttreatment cephalometric superimposition showed maintenance of the skeletal profile, since the patient had no more growth and adequate incisor repositioning (Fig 7). At 3 years posttreatment, the orthodontic results were relatively stable (Figs 8 and 9). The posttreatment periodontal examination involved measurements of sulcus depth, bleeding on probing, and visible plaque. The tests showed an overall good periodontal condition, despite some bleeding on probing
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Fig 4. Posttreatment facial and intraoral photographs at age 35 years 10 months.
and visible plaque (Fig 10). Periodontal probing showed shallow sulcus depths in some teeth and resulted in light bleeding mainly on the palatal surfaces of the mandibular teeth. Likewise, no attachment loss in the form of gingival recession was evident, depicting an excellent periodontal status. DISCUSSION
The planning of dental objectives for a patient with CCD primarily depends on the patient's needs, age at diagnosis, and social and economic circumstances. Because of technical and financial difficulties, this patient started orthodontic treatment at age 23 years, so from adolescence to young adulthood, she had serious functional and psychological problems related to her oral health and poor esthetics. The best-known orthodontic-surgical regimens are the Toronto-Melbourne6,12 and the Jerusalem approaches.7,13 Regardless of the patient's conditions and the protocol to be followed, the aim of dental management in a patient with CCD is to achieve, when
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possible, an optimal functional and cosmetic result by early adulthood. The Toronto-Melbourne approach is based on timed, serial extractions of deciduous teeth; it depends on the extent to which the roots of the permanent teeth have developed, so for this approach, the best period for treatment is in the early stages with a combined oral surgery and orthodontic approach. It is recommended that surgical procedures should begin about 5 to 6 years of age with extraction of the anterior deciduous teeth. Later (6 or 7 years of age), the deciduous incisors are exposed, and healing is allowed; orthodontic brackets are placed on the permanent incisors as soon as possible; and the deciduous posterior teeth are extracted. When the patient is 9 or 10 years of age, the permanent premolars are exposed and allowed to heal. Thereafter, orthodontic brackets are placed on the permanent canines and premolars. During each procedure, which is performed under general anesthesia, the supernumerary teeth are also removed together with the bone covering the underlying permanent teeth.6,12
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Fig 5. Posttreatment study models.
The Jerusalem approach is based on at least 2 surgical interventions, depending on the root development of the permanent dentition. In the first phase, which begins at approximately 10 to 12 years of age, the anterior deciduous teeth and all supernumerary teeth are extracted. In addition, the permanent incisors are exposed, and orthodontic attachments are placed for traction. In phase 2 (age 13 years and older), the posterior deciduous teeth are extracted, the unerupted permanent canines and premolars are exposed, and orthodontic attachments are bonded. At first, according to the Toronto-Melbourne protocol, there would be no need for tooth traction. Therefore, the procedure must begin early in life, and the expectation is that only the removal of bone overlying the permanent teeth with developing roots is sufficient for tooth eruption. In the Jerusalem approach, which begins later in life, traction of the permanent teeth is certainly part of the proposal. In any case, these procedures are all undertaken over a long period. Patient compliance is essential for a favorable outcome for any modality. Starting early with so many surgical procedures can be challenging for a young child but offers the advantage that the patient will have restored function and esthetics in adolescence, which can be psychologically important.
Our patient sought treatment when she was 22 years old, so it was not possible to extract the teeth because of their radicular development. Traction of all unerupted teeth was not possible for this patient, although it was necessary. Another option was extraction of all unerupted teeth and installation of a dental prosthesis or dental implants. This would restore function and esthetics, but the erupted teeth would still require orthodontic alignment. This would have shortened the treatment time, but the patient refused extraction of all unerupted teeth. Her choice was traction of the unerupted teeth, regardless of treatment duration. The orthodontic treatment lasted about 13 years. This seems like a long time, but it is a reasonable time for a patient with CCD. Initially, the barriers (supernumerary and deciduous teeth) were surgically removed, and the first orthodontic challenge was selecting which anchorage to use for traction. It has been suggested that a palatal arch is a better anchor, but not using erupted teeth as anchorage was preferred because the time for traction would be long and the supporting tissues of the teeth could be damaged.13 The initial panoramic view (Fig 3) shows the right permanent first molar with incipient bone
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Fig 7. Pretreatment (black) and posttreatment (red) cephalometric tracings, superimposed on the sellanasion line at sella.
Fig 6. Posttreatment cephalometric and panoramic radiographs.
loss in the mesial face and root canal treatment and extensive coronal restoration of the left permanent first molar, so these were not considered anchors by themselves throughout the traction process. Among the treatment alternatives presented in this case report, one suggests the use of skeletal anchorage to support the traction of all teeth. Skeletal anchorage in orthodontics as absolute anchorage provides new opportunities to guide impacted teeth into occlusion and to treat patients with CCD, making it possible to induce eruption simultaneously of the maxillary and mandibular teeth and consequently reducing patients' treatment times and psychological stress.14 Skeletal anchorage would be the best option for treatment, but when the planning was completed for our patient, conditions for skeletal anchorage were not favorable, so another alternative had to be selected. The option for treatment was the use of a dentomucoperiosteal-supported removable acrylic plate, first in the maxillary arch, because there were not sufficient teeth in the mandibular arch to support a removable plate. As a result, the first teeth to be tractioned were the mandibular ones. If traction supported by skeletal anchorage had been performed, the
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treatment time would have been much shorter. Even without using skeletal anchorage, the result was satisfactory because of the excellent cooperation of the patient, who used the intraoral elastics properly. Some authors have suggested that early surgical management with serial uncovering of the permanent teeth is the best choice.15 Hitchin and Fairley10 believed that the lack of eruption in patients with CCD is due to failure of resorption of the overlying alveolar bone. When these teeth are uncovered, they show a normal eruption pattern. There can also be mechanical interference from impacted supernumerary teeth.15 Still, regarding the causal effect of impacted teeth, there is no statistically significant difference between the amount of either cellular or acellular cementum covering the roots in the patient with CCD and the roots of the control teeth. So the presumption that a lack of cellular cementum causes unerupted teeth is not true.16 Regardless of the cause, it is necessary to stimulate the eruption of unerupted teeth or to force their eruption. Current treatment protocols seem to agree that treatment should begin early, and natural eruption of teeth with roots should be allowed after the removal of obstacles, such as deciduous or supernumerary teeth. In our patient, forced eruption was the only option because all roots were formed. The result was a good bone level at the end of treatment. The patient's periodontal chart (Fig 10) and her initial and final panoramic radiographs showed our follow-up of bone levels in the
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Fig 8. Long-term stability at the 3-year follow-up, with maintenance of adequate overbite and overjet.
teeth that were induced, with an ideal height of crestal bone. During the periodontal examination, the patient had slight bleeding mainly in the lingual aspects of the incisors and the first and second molars, caused by inflammation from plaque. She was instructed again to improve hygiene in these locations. The molar showed a slight bone loss that could not be attributed to the traction of the other teeth. All induced teeth showed excellent periodontal conditions at the follow-up (Fig 10). Some factors contributed to this favorable outcome, including the patient's cooperation regarding her oral hygiene and the use of extrusive forces that were compatible with a good periodontal response. Another factor was that the teeth were positioned on the route of eruption. Since the angle between the orientation of the traction and the central axis of the impacted tooth was smaller, there were more advantages to the eruption of the impacted tooth.17 It is important that the forces be directed to the lingual aspect, never
to the vestibular aspect.18 Another factor to consider was the concern over the bonding technique to allow access to the tooth for induction of eruption; this was done with minimal removal of bone tissue covering the impacted tooth crown for bonding by the closederuption technique. The literature reports a slight loss of attachment around teeth treated by the closed-eruption surgical technique and a mean increase in probing depth, but its magnitude lacks clinical significance.19 The closederuption technique is believed by some to be the best method for uncovering impacted teeth,18,19 and more periodontal and esthetic disadvantages can be expected with the apically positioned flap technique than with the closed-eruption technique.20 When impacted teeth are treated with open surgical exposure, natural eruption and orthodontic alignment have minimal effects on the periodontium, but if necessary an orthodontically induced eruption should be done.21
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Fig 9. Study models 3 years after treatment.
Fig 10. Periodontal chart showing the status at the 3-year follow-up.
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Some peculiarities are seen in the cephalometric measurements of a patient with CCD. Because the base of the skull is smaller than in patients who do not have the syndrome, measurements such as SNA, SNB, and facial angles appear greatly increased compared with normal ones.22 In addition, CCD is usually seen in a brachycephalic patient with horizontal growth, expressed by diminished measurements such as the yaxis, FMA, and SN.GoGn. The patient has these features and shows a restricted pattern of the ANB angle. Because of the shortening of the skull base, the ANB angle is not compatible with the standard skeletal measurements. Thus, the AO-BO, which evaluates the difference between the bone bases without involvement of the skull base, shows the higher values of a Class III malocclusion. Most protocols recommend a LeFort I osteotomy for the correction of skeletal discrepancies; this would have been beneficial to our patient. However, this was not possible because the clinic where she was seen at the time lacked the technical conditions for this procedure. Moreover, she had an acceptable profile before treatment, but the concavity of the profile became more evident, which precluded the standard Class III phases of posttreatment and follow up (Figs 4 and 8). The facial convexity angle also caused the increased concavity of the profile (Table). In this case, jaw advancement surgery would be recommended. Since a patient with CCD has many impacted teeth, the best way to find them is with cone-beam computed tomography, which would give greater predictability to the closed-eruption technique of surgery. Unfortunately, cone-beam computed tomography was not routinely used for localization of impacted teeth when this patient's treatment began. Thus, the method used for uncovering these impacted teeth was only conventional radiographic analysis. The surgical and orthodontic techniques involved in the dental management of this condition are demanding at the levels of diagnosis, treatment planning, and clinical management. Thus, to achieve the best possible result, the highest degrees of orthodontic and surgical cooperation are necessary.12 The orthodontic treatment can be lengthy; this patient was in treatment for approximately 13 years, so it was important to monitor and maintain excellent oral hygiene to keep her dentition healthy. CONCLUSIONS
This case report described a patient with CCD with 11 permanent and supernumerary teeth; she was
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treated by exposure and traction of the viable teeth. The success of the treatment depended on planning and patient cooperation. The treatment provided an ideal occlusion, with satisfactory periodontal results and oral esthetics, and returned important functions to her overall health and social life. Moreover, this approach provided good stability 3 years after the end of treatment. REFERENCES 1. Damm DD, Bouquot JE, Neville BW, Allen C. Oral and maxillofacial pathology. 2nd ed. Philadelphia: Saunders Elsevier; 2008. 2. Farronato G, Maspero C, Farronato D, Gioventu S. Orthodontic treatment in a patient with cleidocranial dysostosis. Angle Orthod 2009;79:178-85. 3. Mundlos S. Cleidocranial dysplasia: clinical and molecular genetics. J Med Genet 1999;36:177-82. 4. Suba Z, Balaton G, Gyulai-Gaal S, Balaton P, Barabas J, Tarjan I. Cleidocranial dysplasia: diagnostic criteria and combined treatment. J Craniofac Surg 2005;16:1122-6. 5. Shafer W, Hine M, Levy B. Shafer's textbook of oral pathology. Delhi, India: Elsevier; 2009. 6. Smylski PT, Woodside DG, Harnett BE. Surgical and orthodontic treatment of cleidocranial dysostosis. Int J Oral Surg 1974;3: 380-5. 7. Becker A, Lustmann J, Shteyer A. Cleidocranial dysplasia: part 1—general principles of the orthodontic and surgical treatment modality. Am J Orthod Dentofacial Orthop 1997;111: 28-33. 8. Nebgen D, Wood RS, Shapiro RD. Management of a mandibular fracture in a patient with cleidocranial dysplasia: report of a case and review of the literature. J Oral Maxillofac Surg 1991; 49:405-9. 9. Winther JE, Khan MW. Cleidocranial dysostosis: report of 4 cases. Dent Pract Dent Rec 1972;22:215-9. 10. Hitchin AD, Fairley JM. Dental management in cleido-cranial dysostosis. Br J Oral Surg 1974;12:46-55. 11. Becktor KB, Becktor JP, Keller EE. Growth analysis of a patient with ectodermal dysplasia treated with endosseous implants: a case report. Int J Oral Maxillofac Implants 2001; 16:864-74. 12. Hall RK, Hyland AL. Combined surgical and orthodontic management of the oral abnormalities in children with cleidocranial dysplasia. Int J Oral Surg 1978;7:267-73. 13. Becker A, Shteyer A, Bimstein E, Lustmann J. Cleidocranial dysplasia: part 2—treatment protocol for the orthodontic and surgical modality. Am J Orthod Dentofacial Orthop 1997;111: 173-83. 14. Kuroda S, Yanagita T, Kyung HM, Takano-Yamamoto T. Titanium screw anchorage for traction of many impacted teeth in a patient with cleidocranial dysplasia. Am J Orthod Dentofacial Orthop 2007;131:666-9. 15. Farrar EL, Van Sickels JE. Early surgical management of cleidocranial dysplasia: a preliminary report. J Oral Maxillofac Surg 1983; 41:527-9. 16. Counts AL, Rohrer MD, Prasad H, Bolen P. An assessment of root cementum in cleidocranial dysplasia. Angle Orthod 2001;71: 293-8. 17. Zhang J, Wang XX, Ma SL, Ru J, Ren XS. 3-dimensional finite element analysis of periodontal stress distribution when
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impacted teeth are tracted. Hua Xi Kou Qiang Yi Xue Za Zhi 2008;26:19-22. 18. Rizzatto SM, Menezes LM, Allgayer S, Batista EL Jr, Freitas MP, Loro RC. Orthodontically induced eruption of a horizontally impacted maxillary central incisor. Am J Orthod Dentofacial Orthop 2013;144:119-29. 19. Becker A, Brin I, Ben-Bassat Y, Zilberman Y, Chaushu S. Closederuption surgical technique for impacted maxillary incisors: a postorthodontic periodontal evaluation. Am J Orthod Dentofacial Orthop 2002;122:9-14.
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20. Vermette ME, Kokich VG, Kennedy DB. Uncovering labially impacted teeth: apically positioned flap and closed-eruption techniques. Angle Orthod 1995;65:23-32. 21. Schmidt AD, Kokich VG. Periodontal response to early uncovering, autonomous eruption, and orthodontic alignment of palatally impacted maxillary canines. Am J Orthod Dentofacial Orthop 2007;131:449-55. 22. Kreiborg S, Jensen BL, Bjork A, Skieller V. Abnormalities of the cranial base in cleidocranial dysostosis. Am J Orthod 1981;79: 549-57.
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