上颌埋伏中切牙对同侧切牙和尖牙方向及位置影响的探讨

An investigation of the influence of impacted maxillary incisor on the orientation and position of lateral incisor and canine

目的探讨上颌埋伏中切牙对同侧侧切牙和尖牙位置及萌出是否存在影响。方法选择单侧上颌中切牙埋伏患者46例,根据埋伏位置分为高位埋伏组及低位埋伏组,对治疗前曲面断层片中埋伏中切牙双侧的侧切牙牙轴与上腭平面的夹角、根尖与上颌中线的距离、近中边缘嵴与上颌中线的距离以及尖牙牙尖与上腭平面间距离进行测量,并进行统计学分析。结果埋伏上颌中切牙同侧侧切牙的牙轴与上腭平面夹角小于对侧,根尖与上颌中线距离大于对侧,尖牙牙尖距上腭平面距离小于对侧,差异均有统计学意义(P<0.05或<0.01);双侧侧切牙近中边缘嵴距上颌中线距离差异无统计学意义(P>0.05);高位埋伏组埋伏牙同侧的侧切牙牙轴与上腭平面夹角小于低位埋伏组(P<0.05或<0.01),其余指标差异无统计学意义(P>0.05)。结论上颌埋伏中切牙可引起同侧侧切牙牙根远中倾斜,对同侧尖牙萌出产生不利影响。

Objective To investigate the relationship between impacted maxillary incisor and the orientation and position of ipsilateral lateral incisor and canine. Methods 46 patients with unilateral impaction of a maxillary central incisor was examined. They were divided into two groups by the depth of impaction（ high and low）. Using the initial panoramic films, the ipsilateral and contralateral lateral incisor＇ s angle, apex to midline , incisal edge to midline and canine height were measured and analyzed statistically. Results There was a significant decrease in the angle of ipsilateral lateral incisor to palatal plane and a larger distance of its apex to midline compared with the contralateral lateral incisor. The ipsilateral canine showed more deeply position than contralateral canine. Significant difference was not found in the distance of lateral incisor＇ s incisal edge to midline. The angle of ipsilateral lateral incisor in high impaction group showed a decrease compared with low impaction group. Conclusion Impacted maxillary central incisor produce a disadvantageous influence on the orientation of ipsilateral lateral incisor and the eruption of ipsilateral canine.