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te, constricted maxillary canines, and a 7 mm overjet (Fig 6 F).
The surgical technique shown in Figures 24 was used to reposition the maxillia superiorly. The anterior portion of the maxilla was raised 7 mm and the posterior portion was raised 9 mm to improve the upper lip - incisor relationship, to facilitate autorotation of the mandible, and to correct the overjet (Fig 6 G). Vertical ostectomies were made in the second premolar regions to facilitate correction of the unilateral cross bite and alignment of the dental arches. By moving the posterior maxillary dento-alveolar segments forward 6 mm, the extraction spaces were closed without retraction of the anterior part of the maxilla. The anterior maxillary segment was sectioned between the central incisors to increase the intercanine width and to improve the first premolar relationship. Facial harmony and occlussal balance were attained after three months of treatment (Fig 6 C, D, H, I). A rhinoplasty is planned for the future to reduce the nasal dorsum and width of the alar bases and to raise the tip of the nose.
- Comment. In patients who display an excessive amount of gingiva and teeth in a position of repose or when smiling, either because of a short upper lip or maxillary alveolar hyperplasia, or both, the entire maxilla or dento-alveolar portion of the maxilla can be repositioned superiorly to improve the upper lip line-to-incisor relationship. The consequent autorotation of the mandible is an effective means of increasing chin prominence. To facilitate superior movement of the maxilla, the maxillary basal spine is reduced under direct vision. The anterior nasal floor can be grooved to accommodate the cartilaginous septum. Submucosal resection of the cartilaginous septum or tubinectomy, or both, may indeed be necessary when the maxilla is superiorly repositioned in excess of 10 mm.
CASE 3 - Figure 7 shows how mandibular prognathism associated with retromaxillism in a 21 - year - old woman was corrected by maxillary advancement, mandibular body ostectomies, and orthodontics. A broad nose, hypoplastic - appearing midfacial region, and prominent chin were the dominant facial features of the patient (Fig 7 A - B). Cephalometric studies showed retroinclination of the maxillary and mandibular anterior teeth (Fig 7 E). Examination of her occlusion disclosed a Class m molar relationship with posterior teeth ill complete cross bite. The maxillary lateral incisors, second and third molars, and mandibular first molars were congenitally missing. The lower anterior dentition was positioned approximately 12 mm anterior to the maxillary dentition. There were 7mm spaces between the right and left mandibular first and second premolars.
After the maxillary and mandibular teeth were aligned and the rotations corrected with edge-wise orthodontic appliances, the maxilla was advanced 6 mm and the mandible was retracted 7 mm simultaneously. Overall facial balance (Fig 7 C - D) was achieved five months later by rhinoplasty (nasal surgery was performed by Dr. Jack P. Gunter, Dallas).
Fig 7 - Case 3. A, B, Preoperative appearance (age, 21 years, 1 months). C, D, Appearance after treatment. E, Cephalometric tracing before surgery (age, 21 year, 7 months) showing mandibular prognathism associated with maxillary restrusion. F: Composite cephalemetric tracing before surgery (age, 21 years, 7 months) and four months after surgery (age 21 year, 11 months)