Biodegradable composite membrane containing oriented needle-like apatites was successfully prepared as follows. The solution of dichloromethane and poly-lactic acid/poly-glycolic acid (PLGA) copolymer was infiltrated to the hydrother-mal-electrochemically deposited apatite and dried in air. After hardening of the film, the composite membrane was prepared by delamination from the titanium plate. The weight changes and the tensile strengths changes of the composite membrane suggest that the apatite inhibited the composite from degradation due to the hy-drolysis of PLGA, and the strength became quite small with the degradation after 2-week soaking in vitro. Histological observation in the soft tissue of rats showed that the around of specimens in both the membranes with and without apatite were cov-ered with fibrous connective tissue. In the hard tissue, the defect in the dura mater was filled with new bone in the membrane with apatite, whereas there was some indication of granulation tissue reaction in the membrane without apatite.
Key words: biodegradation, apatite, composite, membrane, hydrothermal-electrochemical deposition