Treatment of severe unilateral open bite and crossbite in cleft lip and palate patients

European Journal of Orthodontics 6 (1984) 294-3(12 1984 European Orthodontic Society Treatment of severe unilateral open bite and crossbite in cleft lip and palate patients Hans Enemark Aarhus, Denmark Summary. Twenty complete unilateral cleft lip and palate patients 14-17 years of age were.treated for severe crossbite and lateral open bite. Ten patients had the distorted lesser maxillary segment corrected surgically to improve dental occlusion and facial aesthetics. In the same operative procedure a residual oro-nasal fistula was closed, and bone grafting of the maxillary alveolar process bony defect was performed. The immediate results were good, but later complications were observed in form of gingival retraction and vertical segmental relapse. In another group of 10 patients a combined orthodontic-surgical treatment was carried out. The maxillary segment was loosened by a palatal and buccal osteotomy. After one week the maxilla was transversely expanded for 2-3 weeks. The lateral open bite was then corrected by differential vertical elastic traction from flexible sectional arches in the upper jaw to heavy lower ideal arches. The 10 patients treated by this partial maxillary mobilization procedure had, after observation over nearly 2 years, no complications. The treatment is also advantageous in the simplicity of the surgical procedure and reduced treatment time compared with conventional orthodontic treatment. Introduction Some patients with a unilateral cleft lip and palate exhibit severe crossbite at the cleft side, often in combination with a lateral open bite. Orthodontic treatment of these unilateral malocclusions is difficult and time consuming and the results are not always stable. Apart from malocclusion the patients exhibit a depression on the cleft side of the cheek and of the alar base. Therefore it is desirable to expand the basal bone. The ideal orthodontic correction of the lesser maxillary segment is a rotation with the maxillary tuberosity as a fulcrum (Harvold 1954). Clinical experience most often shows a tipping of the teeth with only a slight effect upon the basal bone. A more bodily movement is seen following rapid maxillary expansion (RME), preferably in younger persons before interdigitation or fusion of the median suture (Timms, 1968, Melsen, 1972). However, RME is by nature a bilateral expansion. The optimal goal of these treatments is a unilateral correction of the displaced lesser maxillary segment. This is hardly possible by orthodontic means alone. The purpose of this investigation was to compare the long term results of two orthodontic-surgical treatment methods. In group A the displaced maxillary segment was moved surgically in combination with closure of an oronasal fistula in a one stage procedure. By surgical correction of the lesser maxillary segment it is possible also to expand the basal bone transversely. The main problems are resistance to movement from scar tissue following primary surgery,

TREATMENT OF SEVERE UNILATERAL OPEN BITE AND CROSSBITE IN CLEFT UP AND PALATE PATIENTS 295 and the establishment of a sufficient blood supply post-operatively. After careful total mobilization it is possible to move any segment of the upper jaw in any direction, and by using the tunnelling technique a sufficient blood supply is ensured (Obwegeser, 1965, 1966). West and Epker (1972) reported on 10 patients with posterior unilateral crossbite treated by a posterior maxillary osteotomy. The osteotomy was performed from the buccal aspect with no surgery to the palatal mucosa, however, if a horizontal-lateral movement was desired, they advocated a technique described by Perko (1969), in which palatal mucoperiosteum is mobilized and thereby allows stretching of the adherent palatal mucoperiosteum. Blood supply is maintained from buccal mucoperiosteum following the tunnelling technique. In group B the unilateral transverse and vertical discrepancy was corrected orthodontically after surgical weakening of bony resistance against segment movement. Kole (1959) introduced a corticotomy in combination with orthodontic treatment. Practical experience showed that the teeth moved more rapidly, without excessive tipping. Lines (1975) and Bell and Epker (1976) also reported more rapid orthodontic expansion following segmental maxillary osteotomies. Material The material comprised 20 complete unilateral cleft lip palate patients 14-17 years of age with severe deformation of the lesser maxillary segment. All patients had the same primary operations. At 2 months of age the lip was closed with simultaneous closure of the anterior part of the palate with a Tennison Veau procedure with a double vomerine flap. At 22 months of age the soft palate was repaired by a Wardill push back. Most of our patients with unilateral cleft lip and palate develop a crossbite. Usually crossbites are easily corrected in the mixed dentition. In some cases the transverse expansion of the maxilla is very difficult. Enemark et al. (1973) demonstrated a bony anchylosis across the former cleft in the hard palate. Methods and Results Group A. The 10 patients who had transverse surgical maxillary correction were first orthodontically treated by alignment of teeth over basal bone. Then model surgery was performed to determine whether a good postoperative occlusion could be obtained (Fig. 1). If so the patient was referred to the department of oral surgery, at Aarhus Kommunehospital, where operations were performed. The model surgery showed the surgeon where the segment should be placed and indicated the need for bone grafting of the osteotomy sites. As most of our patients with a unilateral cleft lip and palate need a fistula closure and bone grafting of the alveolar process defect, this procedure was incorporated in the.operation (Enemark et al., 1984). In order to achieve sufficient soft tissue for fistula closure it is necessary to raise two large palatal mucosal flaps. The lateral wall of the maxilla was exposed by the tunnelling technique and osteotomized half a centimeter above apices of teeth from the piriform aperture to the pterygomaxillary junction (Fig. 2). The latter was fractured with a chisel as was the lateral.wall of the nasal cavity. Finally the midpalatal bony anchylosis was fractured. After careful mobilization of the lesser maxillary segment it was placed in the predetermined position by means of a wafer. The. cleft defect was bone grafted by iliac crest cancellous bone and the soft tissue was sutured. If suturing could not be performed without tension, a cheek flap was incorporated. The vertical position of the lesser segment was secured by intermaxillary fixation. As the segment was moved laterally and inferiorly, a bony gap at the site of the buccal osteotomy was also bonegrafted. Intermaxillary fixation was maintained for 8 weeks. After removal of the

296 HANS ENEMARK CASE HJB PRE OP POST OF Figure 1 Case H.J.B. A: Right side complete unilateral cleft lip palate patient with severe crossbite and lateral open bite. B: Model surgery. C: 45 oblique cephalogram preoperatively. D: A good postoperative segmental position. E: Posterio-anterior cephalogram with transverse (t) and vertical (v) correction of the lesser maxillary segment measured at the canine.

TREATMENT OF SEVERE UNILATERAL OPEN BITE AND CROSSBITE IN CLEFT UP AND PALATE PATIENTS 297 Table 1 Movement of the lesser maxillary segment measured at the canine Transverse Vertical Group A x=6.1 mm (2-11 mm) x=5.6 mm (3-10 mm) Group B x=8.4 mm (4-13 mm) x=4.9 mm (3-10 mm) Figure 2 The bone cuts. On Fig. 2A the dotted line indicate the osteotomy at the lateral wall of the maxilla. Fig. 2B, the palatal osteotomy is performed where there is the bony anchylosis (A) in the posterior part of the hard palate. intermaxillary fixation orthodontic treatment was continued until the best possible occlusion was achieved. Transverse and sagittal occlusion were retained with a modified Quad Helix, or a removable prosthesis if missing teeth had to be replaced. The immediate results of the surgical segmental movement were satisfactory (Fig. 1). Measured at the canine the lesser maxillary segment was on average moved 6.1 mm transversely and 5.6 mm vertically (Table 1). After orthodontic treatment was completed patients were (on average) observed over 4 years 11 months (range 3 years 10 months to 6 years 11 months). The long term results were not satisfying. In six of the 10 patients gingival retraction was observed, and in two cases the canine had to be extracted later. Furthermore, in two cases vertical segmental relapse was seen. Group B. Since there appeared to be complications with the one stage procedure 10 additional patients were treated with combined orthodontic surgical maxillary expansion (Fig. 3) followed by fistula operation at a later stage. In this way the loosening of the lesser maxillary segment was a much less extensive operation. Midpalatally only a small flap had to be raised and the cleft side bony anchylosis in the posterior part of the hard palate was fractured. The tunnelling technique was used vestibularly and an osteotomy of the lateral wall of the maxilla was performed. Neither the tuberosity nor the medial wall of the maxillary sinus was touched. After suturing, the orthodontic rapid maxillary expansion appliance was recemented. The patient was dismissed from the hospital 2 days later. The patient was instructed to activate the orthodontic expansion appliance twice a day. Transverse Correction. In 2-3 weeks the maxilla was expanded 7 mm. Clinically the

298 HANS ENEMARK f, Figure 3 Case J.H. A: Pre-treatment condition demonstrating severe asymmetry of the upper jaw. B: After Partial Maxillary Mobilization and 3 weeks of RME. C, D: Before and after RME, demonstrating only slight expansion in the non-cleft side. E: After transverse expansion the vertical discrepancy is corrected in the osteotomy healing period with differential intermaxillary elastics. F: The lateral open bite is usually corrected in 2-3 months. G, H: Pre and post-treatment views demonstrating the effect of the bodily basal bone movement. I: After completion of treatment. J: With temporary bridge restoration.

TREATMENT OF SEVERE UNILATERAL OPEN BITE AND CROSSBITE IN CLEFT LIP AND PALATE PATIENTS 299 expansion was satisfactory with apparently a bodily movement of the loosened maxillary segment. In order to analyse this effect more accurately implants were inserted in two patients (Fig. 4). The distance between the implants situated in the infrazygomatic crest (in the cleft side cranially to the osteotomy) did not change. However, the distance from the midline to the implant situated inferiorly to the osteotomy increased 5 mm. Vertical correction. After RME expansion over 2-3 weeks the rigid appliance in the upper jaw was changed to a more flexible appliance consisting of an upper utility arch 0.16 x 0:16 and sectional arches (Fig. 3). To this appliance selective intermaxillary elastic forces were applied to the fully banded lower jaw with a heavy 0.17 x 0.21 ideal arch. If necessary, scissor bite intermaxillary elastics could be used posteriorly if overcorrection had taken place, and crossbite elastics could be used in the anterior part of the lesser maxillary segment. But most important, these elastics in combination with sectional step down arches were able to correct the lateral open bite in 2-3 months. After correction of the vertical discrepancy, treatment was finished by conventional orthodontics to establish a stable occlusion. As all the unilateral cleft lip and palate patients needed a fistula closure and bone-grafting of the alveolar process defect, this procedure was incorporated in the final orthodontic treatment stage. All 10 patients were successfully treated. Measurements at the canine area indicated an average movement of 8.4 mm transversely and 4.9 mm vertically (Table 1). Following an observation period of 2 years 7 months (range 1 year 10 months to 3 years 8 months) no gingival

300 HANS ENEMARK CASE JH 26.11.1979 6 14YR 5M Figure 4 Posterio-anterior cephalogram with metallic implant B and C in the infrazygomatic crest. D is situated in the incisor region. Implant A placed inferiorly to the osteotomy indicated by an arrow; A is the same implant following 3 weeks of RME. complications or vertical relapses were observed. All maxillae healed firmly. Normal sensation in teeth was measured in all patients within 1 year. Discussion As mentioned by Freihofer (1977) surgical interventions in cleft patients are technically demanding as the movements to be executed are very complex; in a series of 100 osteotomies 9 cleft patients had their maxillary malocclusion corrected by a transversal movement from 4-12 mm measured in the canine area. In six patients a relapse of 30-75% of the operative rotation was observed. Similar relapses were reported by Perko (1969) and Hadjianghelau (1976). Bell and Turvey (1974) demonstrated surgical correction of posterior crossbites in 10 non-cleft patients with normal postoperative gingival health and no segmental relapse. It may therefore be assumed that the scarred

TREATMENT OF SEVERE UNILATERAL OPEN. BITE AND CROSSBITE IN CLEFT UP AND PALATE PATIENTS 301 palatal mucosa is the main reason for the complications. In group A the soft tissue had to be stretched a lot. The lesser maxillary segment was surgically rotated horizontally, tilted laterally in the frontal plane and tipped inferiorly in the sagittal plane. Besides, fistula closure also adds some stretching to the tissue. Obviously, this one stage procedure places excess demands on the tissue. In group B the active segmental movement was achieved more biologically by orthodontic forces over a 2-4 months period. The difficulty in performing unilateral orthodontic movement is to avoid disturbing the normal occlusion in the noncleft side (Wertz 1970). Therefore, as most resistance against lateral movement of basal bone is situated in the zygomatico-maxillary buttress area (Kennedy et al., 1976) a buccally osteotomy is performed from the piriform aperture to the pterygoid-maxillary junction. The latter is not touched since no lateral movement is needed in the posterior part of the segment. Because the double vomerine flap used in primary surgery on these patients, had an osteogenetic potential, leading to formation of a bony anchylosis across the former cleft in the hard palate both demonstrated roentgenologically (Enemark et al., 1973), and histologically (Pruds0 et al., 1974), a palatal osteotomy was also necessary. Only a small palatal flap is raised and the anchylosis is fractured by an osteotome. The active lateral segmental movement is performed by RME. In 2-3 weeks the maxilla is expanded 7 mm without any pain. Clinically, almost no expansion occurs on the non cleft side, thus, not disturbing the normal occlusion on this side. On the cleft side however, 6 mm of expansion is observed by an almost bodily movement of the segment. The 5 mm apical base expansion measured on the two patients with metallic implants is very important for facial aesthetics as the flattened appearance on the cleft side is improved. By using RME the greatest expansion is achieved in the canine area, where most expansion is needed. If overcorrection in the posterior part of the lesser maxillary segment should take place this is easily corrected in the next phase of the treatment. The vertical discrepancy is corrected by intermaxillary elastics in the osteotomy healing period. At this point it is advantageous that the osteotomies in this partial maxillary mobilization procedure do not need bone grafting: Hall and Bell (1976) demonstrated a faster healing in osteotomies with bone grafting. By applying vertical elastic traction to the still loose lesser maxillary segment, it is possible to correct the vertical displacement in 2-3 months. After this period all segments heal firmly, and a stable occlusion is achieved by conventional orthodontics. Fistula closure and bone grafting of the alveolar process defect is incorporated in this stage of the treatment. In this way two hospitalizations are necessary, but as they only last 2 and 4 days respectively it is not felt as a burden to the patients. Furthermore, no intermaxillary fixation is needed. In conclusion, the partial maxillary mobilization procedure where the active movement of the lesser maxillary segment is achieved by orthodontic forces over a period of 2-4 months seems in our experience to be the best solution for treatment of severe unilateral openbites and crossbites. After an observation period of 2 years 7 months on average no complications in form of gingival retraction or segmental relapse have occurred. Address for correspondence Hans Enemark, DDS Aarhus Cleft Palate Clinic, Taleinstituttet, Finsensgade 12 A DK-8000 Aarhus C, Denmark. References Bell W H, Turvey T A 1974 Surgical correction of posterior crossbite. Journal Oral Surgery 32: 811-822

302 HANS ENEMARK Bell W H, Epker B N 1976 Surgical Orthodontic expansion of the maxilla. American Journal of Orthodontics 70: 517-528 Enemark H. Creisen O, Jergensen J 1973 The maxilla in cleft lip and palate patients. Abstract. 2nd International Congress on Cleft Palate. Copenhagen 1973 Enemark H, Krantz-Simonsen E, Schramm J E 1984 Secondary Bone grafting in unilateral cleft lip palate patients: Indications and treatment procedure. International Journal of Oral Surgery. In press Freihofer HPM 1977 Results of osteotomies of the facial skeleton in adolescence. Journal of Maxillo- Facial Surgery 5: 267-297 Hall H D, Bell R A 1976 Combined anterior and posterior maxillary osteotomy. Journal Oral Surgery 34: 126-141 HadjianghelauO 1976 Abstract 3'rd Congress European Association for maxillofacial Surgery. London Harvold E 1954 Cleft lip and palate. American Journal of Orthodontics 40: 493-506 Kennedy J W, Bell W H, Kimbrough O L, James W B 1976 Osteotomy as an adjunct to rapid maxillary expansion. American Journal of Orthodontics 70: 123-137 Kole H 1959 Surgical operations on the alveolar ridge to correct occlusal abnormalities. Oral Surgery, Oral Medicin and Oral Pathology 12: 515-529 Lines P A 1975 Adult rapid maxillary expansion with corticotomy. American Journal of Orthodontics 67: 44-56 Melsen B 1972 A histological study of the influence of sutural morphology and skeletal maturation on rapid palatal expansion in children. Transactions of the European Orthodontic Society 499-507 Obwegeser H 1965 Eingriffe am oberkiefer zur korrektur des progenen zustandsbildes. Schweizerischer Monatsschrift fur Zahnheilkunde, 75: 365-374 Obwegeser H L 1966 Surgery as an adjunct to orthodontics in normal and cleft palate patients. Transactions of the European Orthodontic Society 343-353 Perko M 1969 Die chirurgishe Spatkorrektur von Zahn-und Keiferstellungs anomalien bei Spaltpatienten. Schweizerischer Monatschrift fur Zahnheilkunde, 79: 179-213 Prudso U, Holm P C A, Dahl E, Fogh-Andersen P 1974 Bone formation in palatal clefts subsequent to palato-vomer plasty. Scandinavian Journal of Plastic and Reconstructive Surgery 8: 73-78 Timms D J 1968 An occlusal analysis of lateral maxillary expansion with midpalatal suture opening. Dental Practitioner 18: 435-448 Wertz R A 1970 Skeletal and dental changes accompanying rapid midpalatal suture opening. American Journal of Orthodontics 58: 41-66 West R A, Epker B N 1972 Posterior maxillary surgery: its place in the treatment of dentofacial deformities. Journal Oral Surgery 30: 562-575