3-Dimensional Micro-Computed Tomography Study on Bone Regeneration with Silk Fibroin, rh-Bone Morphogenetic Protein Loaded-Silk Fibroin and Tricalcium Phosphate Coated-Silk Fibroin in Rat Calvaria Defect

The effect of silk fibroin and rhBMP-2 on bone regeneration in rat calvarial defect model

INTRODUCTION: This study evaluated the capability of silk fibroin (SF) and recombinant human bone morphogenetic protein-2 loaded SF (SF-BMP) as a bone defect replacement matrix when grafted in a calvarial bone defect of rats in vivo. MATERIALS AND METHODS: A total 70 calvarial critical size defects (5.0 mm in diameter) made on 35 adult female Sprague-Dawley rats were used in this study. The defects were transplanted with (1) rhBMP-2 loaded silk fibroin graft (SF-BMP: 0.8+10 microg), (2) Silk fibroin (SF: 10 microg), and (3) no graft material (Raw). The samples were evaluated with soft x-rays, alkaline phosphatase activity, calcium/phosphate quantification, histological and histomorphometric analysis at postoperative 4 and 8 weeks. RESULTS: The SF-BMP group (48.86+/-14.92%) had a significantly higher mean percentage bone area than the SF group (24.96+/-11.01%) at postoperative 4 weeks.(P<0.05) In addition, the SF-BMP group (40.01+/-12.43%) had a higher % bone area at postoperative 8 weeks than the SF group (33.26+/-5.15%). The mean ratio of gray scale levels to the host bone showed that the SF-BMP group (0.67+/-0.08) had a higher mean ratio level than the SF group (0.61+/-0.09) at postoperative 8 weeks. These differences were not statistically significant.(P=0.168 and P=0.243, respectively) CONCLUSION: The rhBMP-2 loaded silk fibroin graft revealed fewer immunoreactions and inflammation as well as more new bone formation than the pure silk fibroin graft. Therefore, silk fibroin may be a candidate scaffold for tissue engineered bone regeneration.

Preliminary study on "ridge splitting technique in horizontally deficient alveolar ridge"

AIDS-associated Kaposi 's sarcoma on left lower retromolar triangle and parapharyngeal area : A case report

There are several oral lesions related with AIDS, such as candidiasis, hairy leukoplakia, Kaposi's sarcoma, aphthous stomatitis, lichen planus, and other opportunistic infectious diseases. Among the others, Kaposi's sarcoma, the most common malignant tumor associated with AIDS, is closely linked to the number of CD4+ T cell. Kaposi's sarcoma often occurs in palate, the most prone site, and has characteristic clinical features in most cases. Sometimes, the tumor induces underlying bone destruction at late stage. We report a case of a 27 year-old man with AIDS-associated Kaposi's sarcoma at left lower retromolar triangle, parapharyngeal area and discuss the management of AIDS patients in dentistry.