利用锥形束CT研究单侧上颌尖牙埋伏阻生患者牙弓形态特点

A CBCT study on Morphological characteristics of dental arches in subjects with unilateral maxillary canine impaction

目的 利用锥形束CT（Cone beam computed tomography,CBCT）研究单侧上颌尖牙埋伏阻生患者牙弓形态特点,为研究其病因及预防继发病症提供参考.方法 39名单侧上颌尖牙埋伏阻生患者,其中腭侧埋伏19名,唇侧埋伏20名,另设正常对照20名.三组患者年龄无显著性差异.三组患者拍摄CBCT并对牙弓的影像进行测量,比较三组之间以及阻生侧与非阻生侧的牙弓形态特点.结果 尖牙阻生患者的双侧牙弓比较显示,阻生侧前段及整侧牙弓长度均比非阻生侧小（P＜0.001）.腭侧组第一磨牙到腭中缝距离（24.06±1.68） mm小于唇侧组（24.86±1.31）mm和对照组（24.88±1.12） mm,腭侧组牙弓周长（72.29±3.50） mm小于唇侧组（75.96±5.26） mm,P＜0.05.结论 上颌尖牙埋伏阻生可能与牙弓长度（尤其是前段）较短有关,且腭侧阻生可能还与牙弓宽度较小有关.

Objective To examine the relationship between unilateral maxillary canine impaction and the morphological characteristics of the maxillary dental arches using Cone beam computed tomography（CBCT）.Methods 39 patients with unilateral impacted canine were selected,including 19 palatal impaction （UPI） （mean age：16.21 ± 4.14 years） and 20 buccal impaction （UBI）.20 normal patients served as control,with matched ages.CBCT images for the three groups were taken and compared for arch character±estics.Results The anterior and whole dental arch lengths of impaction side were smaller than that of normal sides （P〈0.001）.The first molar to midpalatal suture distances of UPI group were smaller than the other groups and the arch perimeter of it was smaller than UBI group（P〈0.05）.Conclusions The short arch lengths （especially in anterior part） may have effect on the occurrence of unilateral maxillary canine impaction.UPI may also be related to a smaller arch width.