Objeract:To evaluate the effects of controlled release tinidazole(TNZ) membrane in the treatment of adult periodontitis. Methods:Adult periodontitis was treated with TNZ membrane in 15 cases (25 teeth),with Metronidazole(MNZ) in 15 cases (24 teeth) and with vehicle membrane in 15 cases (25 teeth).The effects were evaluated by clinical observation,biochemical examination and becteria test. Results: TNZ membrane more significantly inhibited bacteria (P