A little positive cells were found in the control group, and there was no difference between the ringle and the central tissues. The difference between the apoptotic index of the experimental group and the control group was very significant ( P0.01). 对照组标本中仅发现极少数阳性细胞,且其中心区与边缘区无统计学差异,其凋亡细胞指数与治疗组标本相比,差异均非常显著(只0.01)。