不同生长期平导对牙根吸收影响的比较研究

目的：比较不同生长期使用平导对牙根吸收影响。方法：选用90例经标准方丝弓矫治技术矫治的病例，每个患者在戴平导前、停戴平导时、停戴平导6个月时分别拍摄全口曲面断层片，分别测量下颌中切牙及侧切牙牙根等级，分析不同生长期牙根吸收情况及发生频率的分布情况。结果：男性及女性戴平导前不同生长期牙根吸收等级的差异无统计学意义（P〉0．05），男性及女性停戴平导时、停戴平导6个月时牙根吸收等级的差异均有统计学意义（P〈0．05），且16岁后比16岁前的牙根吸收比例要高。结论：不同生长期使用平导造成牙根吸收有区别。

CLINICAL STUDY OF THE INFLUENCE ON ROOT RESORPTION BY FLAT BITE PLATE TREATMENT DURING DIFFERENT GROWTH PERIOD

Objective：To understand the root resorption caused by fiat bite plate treatment during different growth period. Methods：90 patients ,treated with edgewise technique were chosen,All patients were taken panoramic radiograph before,soon after, and 6 months after flat bite plate treatment,the root grade of lower incisor and lower lateral incisor was measured,and the extent and the freguency of the root resorption were andlyzed.Results：There was no statistically significant difterence before flat bite plate treatment between male and female and different growth period; there was significant difterence between male and female soon after flat bite plate treatment and 6 months after that, and the root resorption was higher in group of 〉16y than in group of 〈16y. Conclusion：The root resorption causeed by flat bite plate is different during different growth period.