RESUMO
PURPOSE: We carried out guided bone regeneration of cranial bone defects in rats using the bovine bone substitute Bio-Oss and a collagen membrane and performed histological observations of the bone repair process. MATERIALS AND METHODS: Bone defects were created in the cranial bones of 30 15-week-old Sprague-Dawley rats. We made 3 groups. A is unfilled, B is Bio-Oss, and C is Bio-Oss plus a collagen membrane. At 4 or 8 weeks postoperatively, tissue samples were taken. The Kawamoto technique was used for histological evaluation. RESULTS: There was no new bone formation in group A. In groups B and C, new bone formation was evident around the Bio-Oss. In group C, new bone formation was evident in the centers of the bone defects, detached from the cut edge of the cranial bone. CONCLUSION: Our results suggested that the Bio-Oss acts as a scaffold for bone repair, and the use of a collagen membrane may anchor the Bio-Oss closely to the cranial bone and assist the bone repair response.
RESUMO
Although many oral ulcers have similar clinical appearances, their etiologies can range from reactive to neoplastic to oral manifestations of dermatological diseases. In patients with an HIV infection, fungal diseases may cause ulceration in the oral cavity; however, there have been few studies of oral ulcerative lesions associated with Candida in patients without an HIV infection. Nevertheless, we encountered chronic oral ulcer associated with Candida among our frequent outpatients without an HIV infection. The present article reviews the causes of oral ulcers, focusing on Candida as a protractive factor for chronic oral ulcers, and it is recommended that Candida involvement be considered in diagnosis of a certain chronic oral ulcer, that remains of unknown origin even if some examinations have been performed.