中文摘要：

目的：探讨P物质纳米缓释微球对正畸牙齿移动速度的影响。方法：选择16例需要拔除上颌第一前磨牙的样本,进行配对实验研究,所有样本均采用固定标准方丝弓矫治器,以150g的力拉尖牙向远中移动;在实验侧尖牙颊侧及腭侧根尖水平牙龈粘膜下注射5×10^-3mg人P物质纳米缓释剂,两周注射一次。结果：经过4周的观察,发现实验侧上颌尖牙移动的距离比对照侧增加30.02%。结论：局部注射P物质纳米缓释剂可以加速牙齿移动。

英文摘要：

Objective To investigate the effects of SP-PLGA NP on the othodontic tooth movement. Methods This study involved 16 cases of extraction of the bialateral upper premolars. Canine was moved distally by exertion of 150g of force. Fixed orthodontic appliances were used in these cases.SP-PLGA NP was injected into the subgingival tissues of the canine every two weeks.The accumulated distance of canine movement were observed and were compared with those of the control group. Results It shows that the speed of tooth movement of SP-PLGA NP group was 30.02% higher than the control group. Conclusion The results indicated substance P could promote the tooth movement.