牙周再生膜片之生物性質評估

This study was to examine the historical changes of implanted three commercial GTR (Guided Tissue Regeneration) membranes for confirming the clinical feasibility in vitro and vivo. Among the resorbable GTR membranes, the collagen membrane is collagen base, and the PLA-PGA membrane is synthesized membrane, while the e-PTFE (Expanded polytetrafluoroethylene) is synthesized but nonresorbable. The membrane material was placed on the bottom of the hole of prepared culture well, then 2 culture wells were assembled to a study device by silicone sealing. And all of devices were placed in 24 wells culture plate. After 24 hours incubation, flowcytometric analysis was performed to measure the numbers of cells in the collection. Membranes were observed at SEM on both up-side and downside. Then Beagle dogs were used as animal model. Buccal mucoperiosteal flaps were reflected in the bilateral mandibular premolar and molar areas. Buccal alveolar bone was reduced on 1st and 2nd premolar and molar to a level 5 mm apical to the cemento-enemel junction (CEJ). Root surface was denuded of periodontal ligament and cementum, and notches were placed at the bone level of each root. The tested GTR barriers were implanted in critical bone defect areas. Flaps were coronally positioned and sutured. Two beagle dogs were sacrificed each time as the designed time period after surgery. Histological and histometirc evaluation at 7 days, 14 days, 28 days, 3 months were performed postoperatively to determine the healing response of each treatment modality. Both the cementum height and bone height were measured as the index of tissue occlusion effect. Like all resorbable GTR membrane, the collagen membrane and the PLA-PGA membrane were observed membrane resorption and cells infiltration in the fibril network after 24 hours incubation. But the collagen membrane and the PLA-PGA membrane enhanced the cementum regeneration of 2.6mm and 2.47mm averagely after 3months implantation. On the contrast, cementum height of 2.31 mm was observed in e-PTFE group. The collagen membrane and the PLA-PGA membrane seemed to be efficient in treatment of Guided Tissue Regeneration.