前磨牙桩道形态的CBCT分析

Morphology study of the post space of permanent premolars by cone-beam computed tomography

目的通过CBCT图像重建,分析中国人前磨牙牙齿基本形态以及牙根桩道段解剖形态,为临床上前磨牙桩道预备和成品桩的设计提供参考数据。方法依照纳入标准选取60名在华西口腔医院放射科进行全颌面部CBCT扫描的患者,共计480颗双侧上下颌前磨牙,分析牙齿基本解剖形态、牙根桩道段长度、桩道末端根尖直径、牙根锥度等测量指标并进行统计学分析。结果同性别双侧前磨牙桩道段长度和桩道根尖末端直径均无显著性差异(P>0.05)。左侧上颌第二前磨牙桩道段长度和右侧下颌第二前磨牙桩道根尖末端直径在不同性别之间有显著性差异(P<0.05),其余指标的性别差异均无统计学意义(P>0.05)。任何牙位的牙根锥度从根冠至根尖均呈减小趋势,根冠1/3、根中1/3和根尖1/3的锥度平均值分别为0.3、0.22和0.18。结论本研究初步为设计符合国人牙根形态的成品桩提供了牙根形态和结构的理论参考。

Objective To investigate the morphology of the post space of 480 permanent premolars in Chengdu region by cone-beam computed tomography （CBCT） and to provide anatomic data for the design of fabricated posts. Methods CBCT images data of 480 premolars from 60 patients were obtained. The length and the diameter of the post space were measured. The taper of the roots was calculated and analyzed. The data were analyzed with SPSS 20.0 software package. Results There was no significant difference in the length and the root tip diameter of the bilateral premolars of the same gender. There was a significant difference in the length of the post space of left maxillary second premolars and the root tip diameter of the right mandibular second premolars between different genders. The taper from cervical region to apical region was reduced gradually and the average values of cervical, middle and apical region were 0.3, 0.22 and 0.18, respectively. Conclusion This study provides a theoretical reference for the design of the root morphology and structure in accordance with the Chinese people.