Systematic analysis of clinical outcomes of anterior maxillary and mandibular subapical osteotomy with preoperative modeling in the treatment of bimaxillary protrusion.

The purpose of this study was to determine the changes in teeth and hard tissues after preoperative modeling and bimaxillary anterior subapical osteotomy for the treatment of bimaxillary protrusion. Cephalometric analysis was used to evaluate the aesthetic effects and occlusal relationships obtained. The subjects included 19 women and 1 man (aged 19-41 years; average, 29 years) with bimaxillary protrusion who underwent anterior subapical osteotomy of both the maxilla and mandible, with simultaneous genioplasty, if required. Based on a preoperative computer-aided manufacturing/design-assisted and model surgical design and an occlusal guide plate, new occlusal relationships were established for the patients. In addition, the preoperative and postoperative cephalometric radiographs were systematically analyzed. In all patients, the surgical incisions underwent primary healing, with no infection or osteonecrosis. Significant differences were observed in the preoperative and postoperative values of all hard tissue and teeth parameters, except for SGn-FH degrees and Co-MP. The most obvious significant differences were seen in L1-OP°, Id-Pog-Go°, IIA°, U1E-Apog, L1E-Apog, U1E-NA, and L1-NA° (P < 0.001). Postoperative follow-up lasted for 12 to 36 months. All patients eventually achieved normal jaw relationships, tooth arch forms, and Spee curves. No evident irregularities of teeth arrangement or abnormal occlusal relationships were observed. All patients were satisfied with their postoperative facial appearance, except for 1 patient, who underwent repeat surgery because of relapse. With the use of a precise preoperative model surgical design, orthognathic surgery, a simple and time-saving technique, can be used to correct bimaxillary protrusion with satisfactory postoperative occlusal relationship and facial aesthetic appearance and minimal postoperative complications.

Surgical treatment of craniomaxillofacial fibrous dysplasia: functionally or aesthetically?

BACKGROUND: Fibrous dysplasia (FD) is a tumor-like growth that consists of replacement of the medullary bone with fibrous tissue, causing the expansion and weakening of the areas of bone involved. The most commonly affected bones are facial bones, causing a number of facial cosmetic and functional problems. METHODS: From December 2008 to July 2012, 10 patients with craniomaxillofacial fibrous dysplasia were treated by conservative resection and local recontouring. The patients were followed up yearly, with an average of 3 years; the longest follow-up period was 5 years. RESULTS: All the 10 patients received appropriate treatment and histopathological examinations were performed to confirm the diagnosis of FD. Four patients with zygoma involved had received partial zygoma osteoectomy and 2 patients received mandibular partial osteoectomy. Average time of follow-up was 3 years, with a range from 1 to 5 years, and all patients obtained satisfactory aesthetic and functional results. CONCLUSION: In most patients, a conservative surgery will achieve good functional and aesthetic results. For patients with mild symptoms, the aesthetic effect should be given priority while for the heavier patients the restoration of function and aesthetic effects should all be taken into account.

Ectopic osteogenesis of allogeneic bone mesenchymal stem cells loading on ß-tricalcium phosphate in canines.

BACKGROUND: Bone mesenchymal stem cells are progenitor cells for mesenchymal tissues. The objective of this study was to evaluate the subcutaneous ectopic osteogenesis of allogeneic bone mesenchymal stem cells, which were loaded on ß-tricalcium phosphate in canines without immunosuppressive therapy. METHODS: Osteoinduced allogeneic bone mesenchymal stem cells were seeded onto a ß-tricalcium phosphate scaffold to construct tissue-engineered bone. Four dogs (recipients) in the allogeneic group were subcutaneously implanted with the allogeneic bone mesenchymal stem cells/scaffold; four dogs (donors) in the autogeneic group were implanted with the autogeneic bone mesenchymal stem cells/scaffold complex; and four dogs in the control group were implanted with scaffold alone. Systemic immune responses were evaluated by measuring the T-lymphocyte CD4, CD8, and CD4/CD8 subsets of each group. Subcutaneous osteogenesis was compared between the three groups by histologic analysis at week 24 after implantation. RESULTS: Flow cytometry showed no significant differences in the number of CD4 and CD8 T cells and the CD4/CD8 T-cell ratios among the three groups. Histologically, at week 24, both the autogeneic and allogeneic complexes led to subcutaneous osteogenesis, whereas the control group alone did not. There were no significant differences in the percentage of osteogenic area between the allogeneic and the autogeneic complexes on histomorphometric analysis (p > 0.05), which was significantly higher than that produced by the control group alone (p < 0.001). CONCLUSION: The results demonstrate that osteoinduced, allogeneic bone mesenchymal stem cells loaded on ß-tricalcium phosphate enhanced ectopic bone formation in canines without immunosuppressive therapy.