The histopathologic observations six months later showed: the curative rate of NMA group was 60%, there was no statistical difference among the curative rates of these three groups (P > 0.05).

• 6月个后经组织病理学观察发现:新磁胶的有效率为60%25；与另外两种材料在疗效上无差异(P>0.；05)。