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PURPOSE: Implant placement in the posterior maxilla may often be contraindicated because of insufficient bone volume and the presence of the maxillary sinus. In these situations, sinus floor lifting and grafting frequently have been proposed as the best treatment. The aim of this study was to compare histologically the use of 100% autogenous bone versus a combination of autogenous bone and corticocancellous pig bone for maxillary sinus augmentation. MATERIALS AND METHODS: Eighteen patients requiring bilateral maxillary sinus augmentation were selected for this study. Bone for grafting was harvested from the iliac crest. Each patient received 100% autogenous bone in 1 randomly selected sinus (control side) and a 1:1 mixture of autogenous bone and corticocancellous pig bone particles in the contralateral sinus (test side). Five months after the augmentation procedure, bone biopsy specimens were taken at the time of implant placement. RESULTS: No complications were observed during the surgical procedures; all patients healed uneventfully. No signs or symptoms of maxillary sinus disease were observed during the 5 months after surgery. No significant differences in bone percentages were observed in the bone biopsies from test and control sides. DISCUSSION AND CONCLUSION: It could be concluded from this study that corticocancellous pig bone particles can be successfully used in a 1:1 mixture with autogenous bone from the iliac crest for maxillary sinus augmentation in cases of severely atrophic maxilla.  相似文献   
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The sample of patients analyzed has been selected from 66 cases treated for extraoral bone-anchored implantology at the Plastic and Reconstructive Surgery Department of the "Tor Vergata" University of Rome. Optimal results can be obtained in the ear district because of the low surgical risks and few postsurgical complications. Advantages offered by extraoral bone integrated implants are obvious when compared with more traditional techniques: it is possible to obtain a better cosmetic result only from 2 surgical sessions; and adhesive prosthesis may be better placed without the usual local irritation, achieving a correct positioning. The authors present their experiences in using extraoral implants for the reconstruction of the ear area malformation.  相似文献   
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BACKGROUND: Recently, the use of titanium micromesh for alveolar bone augmentation has drawn interest; however, only limited histologic data are available on the quality of the bone regenerated. Therefore, this study compared the use of 100% intraoral autogenous bone to a combination of intraoral autogenous bone (70%) and bovine porous bone mineral (BPBM) (30%) for alveolar ridge augmentation with titanium micromesh histologically and histomorphometrically. METHODS: Twelve partially edentulous patients required alveolar bone augmentation before implant insertion because of ridge resorption. The defect sites, six in the maxilla and six in the mandible, were reconstructed with particulate autologous bone (control group, N = 6) or a mixture of autologous bone and BPBM (test group, N = 6) in combination with titanium micromesh. Core biopsies were taken from the defect sites 8 to 9 months after grafting at the time of implant insertion. RESULTS: Newly formed compact bone with a well-organized lamellar pattern was identified in all specimens. In the samples taken from the test group, the BPBM particles were surrounded completely by newly formed bone with no signs of resorption. The mean total bone volume was 62.38% +/- 13.02% in the control group and 52.88% +/- 11.47% in the test group. The soft tissue volume was 37.61% +/- 13.02% and 29.96% +/- 12.58%, respectively, and the residual BPBM volume was 17.15% +/- 2.72% in the test group. No statistical difference was observed in the histologic parameters evaluated, irrespective of graft type and site (P >0.05). CONCLUSION: Within the limits of this study, BPBM (30%) in combination with autogenous bone (70%) did not yield a lower percentage of new bone formed compared to autogenous bone alone in ridge augmentation with titanium micromesh.  相似文献   
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Clefts of the orofacial region are among the most common facial defects and are caused by abnormal facial development during gestation. Cleft lip with or without cleft palate (CL/P) is a birth defect with a complex etiology resulting from a mixture of genetic and environmental factors. In the present study we considered myosin 14 ( MYH14 ) as a candidate gene for CL/P. This gene codes for the heavy chain of non-muscle myosin IIC (NMMHC-IIC), maps in the OFC3 region, and shares significant homology with myosin 9, a gene that our group has recently seen to be involved in CL/P. A linkage disequilibrium investigation was conducted with six single nucleotide polymorphisms in MYH14 and a sample of 239 CL/P nonsyndromic patients and their parents. Our family-based investigation provided no evidence of association between MYH14 and CL/P alleles. These data do not support the involvement of MYH14 in CL/P among the Italian population.  相似文献   
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