|Budget Amount *help
¥3,200,000 (Direct Cost : ¥3,200,000)
Fiscal Year 1999 : ¥1,000,000 (Direct Cost : ¥1,000,000)
Fiscal Year 1998 : ¥2,200,000 (Direct Cost : ¥2,200,000)
The purpose of this study was to investigate the effectiveness of the regeneration around artificial bone defects and extraction sockets using electrified membrane, and to compare the effectiveness of membrane to GTAM【○!R】. Electrified membranes were absorbable poly-L-lactic acid (PLLA) membrane and non- absorbable VDF/TrFE membrane.
At first, Wis tar-strain male rats, ages 13 to 15 weeks, were used. A hole of 2.0 mm in diameter was drilled in the femoral diaphysis. The control group's, experimental site was covered with only soft tissue, Group A's with GTAM【○!R】, Group B's non-electrified PLA, Group C's and D's with PLLA membrane (Mw=10 X 1OィイD14ィエD1 or 30 X 10ィイD14ィエD1). The experimental periods were 2 and 4 weeks. Microscopic histopathological observations were made.
Second experiment was to compare the effectiveness of two methods using GTAM【○!R】 and other using non-absorbable VDF/TrFE membrane as barrier membranes on bone regeneration around the extraction sockets. Six beagle dogs P3 and P4 were removed. Group A' s experiment site was covered with expanded-polytetrafluoroethylene, Group B' s was covered with VDF/TrFE membrane, and the control groups was covered with only mucoperiosteum flap. Experimental periods were 2, 4 and 6 weeks, histopathological and bone histomnorphomnetric observations were made.
The electrified membrane groups showed more accelerated bone growth and bone maturity than did the GTAM【○!R】 groups in the early stages. Especially in the 30 X 10ィイD14ィエD1 Mw PLLA group, where a greater amount of bone tissue and increase of maturity was observed. Results of the GTAM【○!R】 groups were almost the same as time control group, and inferior to the electrified membrane groups through all experimental periods. PLLA is easily shaped to fit bone surface to maintain desired space. PLLA film might therefore be used in clinical application in guided bone regeneration.