Soft tissue changes associated with mandibular subapical osteotomy.

Sophisticated treatment planning for those individuals with severe dental and facial disproportions requires accurate prediction of posttreatment results. Preand posttreatment cephalometric X-rays for a group of twelve patients treated by a combined orthodontic-oral surgical approach were evaluated. The surgery was of either the standard mandibular subapical osteotomy or Kole type of procedure. Surgical repositioning of the anterior mandibular alveolus resulted in various changes in hard tissue and soft tissue profile. In summary, these changes were: 1. Decreased lower facial height. 2. More relaxed lip posture as revealed by an increased superior vermilion lip length and decreased inferior vermilion lip length. 3. Stomion moved inferior and posterior relative to the lower facial plane. 4. Superior labial sulcus became less concave. 5. Inferior labial sulcus became more concave. 6. Superior vermilion and inferior vermilion moved posterior relative to the lower facial plane. 7. Chin radius and lip-chin-throat angle decreased. 8. Overbite and overjet increased while Wits analysis decreased. 9. Facial contour angle was unchanged. Changes were similar for both standard subapical and Kole groups with the main difference being a greater reduction in facial height with the Kole group.     

Treatment of skeletal class II deformity by mandibular osteotomy and bone grafting

An operation is described to correct the Angles Class II Division I deformity in the patient who wishes to avoid lengthy orthodontic preparation of the dental arches. Repositioning of the anterior mandibular teeth and alveolar process, together with the chin is achieved without hazard to the teeth or the inferior dental neuro-vascular bundle. Interpositional bone grafting is an essential part of the technique.     

Pulp changes after anterior mandibular subapical osteotomy in a primate model.

Subapical osteotomy of the anterior mandible was carried out on 10 adult Macaca Irus monkeys with and without open bite. Teeth were extracted at 8 weeks, 12 weeks, 24 weeks and 1 year after surgery and the pulps examined histologically. No normal pulps were found. Progressive fibrosis and calcification was noted in all teeth. Patent pulp blood vessels were found up to 24 weeks after surgery. Pulp damage to teeth distal to the osteotomy site was found in 50% of cases. Control teeth extracted from the opposing jaw at the same intervals were all found to have normal pulps.     

Anterior mandibular subapical osteotomy: a useful treatment for patients with severely worn mandibular anterior teeth.

Rehabilitation of patients with severe dental wear is a complex diagnostic and restorative problem. As wear occurs, space for restorative materials is lost, and unique treatment techniques are needed to provide good esthetics and function. Use of orthognathic surgery to reposition mandibular anterior teeth and supporting alveolar bone can create a more ideal environment for restorative procedures.     

Stability of skeletal Class II correction with 2 surgical techniques: the sagittal split ramus osteotomy and the total mandibular subapical alveolar osteotomy.

Combined orthodontic and surgical treatment of severe Class II dentoskeletal deformities with the use of the bilateral sagittal split ramus osteotomy is a routine procedure in orthodontic practices. However, an alternative surgical technique, the total mandibular subapical alveolar osteotomy, could be used for the same purpose. The aim of this investigation was to compare the stability of the sagittal split ramus osteotomy with the total mandibular subapical alveolar osteotomy in the correction of dentoskeletal Class II malocclusions. Forty patients that exhibited Class II dentoskeletal relationships were included in the study. Twenty of these patients had mandibular advancement with the sagittal split ramus osteotomy; the remaining 20 patients had advancement of the whole lower alveolar segment with the total mandibular subapical alveolar osteotomy. The cephalograms studied were taken before the surgical procedure (T1 = 4 weeks before operation), immediately after the procedure (T2 = 10 days after surgery), and 1 year later (T3). The statistical analysis used to assess the results between and within the groups over the different time periods was the analysis of variance. The regression analysis was used to test the interdependence of soft tissue response to hard tissue movement. The results of this study show that both procedures are equally stable when correcting Class II malocclusions. This was proved by the stability of the correction of overjet, B point, and incisor-mandibular plane angle. There were no statistically significant differences between or within the groups in the position of these landmarks over time. There was a statistically significant change in the position of pogonion from T1 to T2 (P <.0028) between the groups, although at T3 this difference was not significant (P <.05). There were no significant changes in face height either within or between the groups over time. The hard/soft tissue interactions for the total mandibular subapical alveolar osteotomy were as follows: The lower lip advanced 60% to the incisor movement; soft tissue B' point responded with a 130% advancement in relation to the change in its hard tissue counterpart. Soft tissue pogonion advanced 90% in relation to the hard tissue landmark. The data suggest that the total mandibular alveolar osteotomy is the treatment of choice for the correction of severe dentoalveolar retrusive Class II malocclusion for which alteration of the mentolabial sulcus is desirable.     

Correction of class II malocclusion by combined sagittal ramus and subapical body osteotomy.

The complete mandibular subapical osteotomy has been presented as a method for correction of Class II malocclusions. At this point, it holds some promise as a solution to the skeletal relapse seen in the surgical correction of Class II malocclusions with use of other techniques. The procedure is a straight-forward combination of the sagittal osteotomy as described by Obwegeser and the subapical osteotomy as described by K?le. Further investigation into the versatility of this procedure is recommended.     

Two ways to correct bird-face deformity

Two different ways of correcting micromandibularism inherent in the bird-face deformity have been described. Both procedures may be applied to correct the symmetric or the asymmetric types of bird-face deformity. Both have the elongation in the front area by means of one- or two-step advancement genioplasty in common. The difference between the two procedures lies mainly in the way the elongation of the mandibular body is achieved. Procedure 2 advocates the elongation of the mandible by means of vertical osteotomy within the tooth-bearing area, and procedure 1 advocates the elongation of the mandible behind the tooth-bearing area by means of the extended sagittal split osteotomy. Both procedures are demonstrated by drawings and by cases of patients who have been operated on.     

Total mandibular alveolar osteotomy: an alternate choice to other surgical procedures

Patients whose facial esthetics are not severely compromised but who need surgical intervention for the correction of a dentoskeletal problem can be treated by repositioning of the whole mandibular alveolar segment in the direction needed to allow for such correction. The challenge to achieve efficient and relatively stable results with the use of combined orthodontic and surgical methods has been met by the use of various surgical techniques. The lower total alveolar osteotomy is another viable surgical technique that could be considered when treatment is being planned in an orthognathic surgical case. Its indications, contraindications, advantages, and disadvantages are described, and cases are reported to exemplify problems that can be corrected with this approach.     

Treatment of severe mandibular retrusion in class II, division 2 malocclusion.

The case of an adult patient with a severe mandibular retrusion of the Class II, Division 2 malocclusion type has been presented. The patient's marked anteroposterior discrepancy was complicated by the severe malocclusion. The solution to this case involved presurgical orthodontic treatment to allow for surgical mandibular advancement by a modified sagittal osteotomy and postsurgical orthodontic care for alignment of the dentition. A discussion of the importance of the patient's facial growth type for stable mandibular advancement has also been presented.     

Obwegeser II osteotomy (transoral angle osteotomy) for open bite with skeletal class III deformity

IntroductionThis study evaluated postoperative stability after Obwegeser II osteotomy (transoral angle osteotomy, first reported by Obwegeser 1973) for severe open bite with mandibular prognathism.Patients and methodsThis retrospective study reviewed 20 consecutive patients who underwent only mandibular Obwegeser II osteotomy to correct open bite and mandibular prognathism. Lateral cephalograms were evaluated preoperatively (T1), immediate postoperatively (T2) and at least 6 months after the surgery (T3). Surgical and postsurgical changes in cephalometric measurements were evaluated statistically.ResultsOpen bite with skeletal class III malocclusion was corrected by the Obwegeser II osteotomy alone. After an average of 9.9 ± 5.2 mm of mandibular setback with open bite closure (T2–T1, over-bite change, 5.7 ± 2.4 mm) by counter-clockwise rotation of the mandible, the patients showed 0.8 ± 1.7 mm of horizontal relapse (p > 0.05), 1.1 ± 1.7 mm of vertical relapse at the B point (p = 0.011) and −0.2 ± 1.6 mm of over-bite change postoperatively (T3–T2).DiscussionWith the adequate control of the condylar position with rigid internal fixation, Obwegeser II osteotomy showed acceptable stability after the correction of open bite with mandibular prognathism without a simultaneous maxillary osteotomy. An isolated Obwegeser II osteotomy can be considered a reliable option in cases with moderate to severe open bite with mandibular prognathism when the maxillary osteotomy is not needed if the patients have a well-positioned maxilla.     

A comparison of profile changes between ramus and anterior mandibular subapical osteotomies in class III Chinese patients

The purpose of this study was to compare cephalometrically the differences in soft-tissue profile changes produced by intraoral ramus and anterior subapical osteotomies for the treatment of Chinese patients with class III malocclusion. Thirty-seven Chinese adults whose class III malocclusion was treated either with an intraoral ramus (group A) or an anterior subapical (group B) osteotomy were selected for the study. Serial lateral cephalograms taken presurgically (T1) and at least 6 months postrentention (T2), showed marked improvement in the soft-tissue profile in both groups. Although the percentage response of soft- to hard-tissue movement was similar at lebrale inferius, the response at soft-tissue point B was found to be statistically less in group B than in group A (P less than .05). Although the correlation between the upper lip response to mandibular ramus setback in group A was weak (r = 0.11), there appeared to be a relatively strong correlation between posterior movement of the upper lip and the magnitude of the lower segmental setback (r = 0.65). The differences in soft- to hard-tissue response with the two osteotomy procedures appear to vary with those reported in whites. This study emphasizes the need for different prediction ratios of soft- to hard-tissue movement in different racial types.