The Guided Tissue Regeneration therapy using absorbable / non-absorbable membrane is applied to insurance in April, 2008, and attract attention again. The GC membrane was developed as a bioabsorbable membrane for Guided Tissue Regeneration, and was put on the market as first bioabsorbable product in domestic in 1996. The GC membrane made from a lactic acid-glycolic acid copolymer which is a synthetic polymer has the porus structure, maintaining supply of body fluid, preventing downgrowth of connective tissue. And after healing, GC membrane is absorbed by hydrolysis.