The tested teeth were extracted 2 weeks, 4 weeks, 12 weeks, and 6 months after the operation.The extracted teeth were examined histopathologically.

• 分别于术后2、4、12 周、6 个月将小型猪快速处死，本文是随机抽样不同时期的4 个对照牙经固定，超声快速脱钙做组织切片，在光镜下观察。