which was (4.92±0.38) mm in the control group. Both groups had better attachment level than those before treatment (P<0.05)， while the difference had no statistical significance between the two groups (P>0.05). Conclusion Combination of oral tissue patch and bone powder provides excellent clinical effect in treating grade Ⅲ furcation defect， and this method shows accelerating effect for periodontium regeneration.

    【Key words】 Oral tissue patch； Bone powder； Grade Ⅲ furcation defect； Clinical effect

    根分叉病变是牙周炎发展到较为严重程度后病变累及到多根牙的根分叉区 ......