显微CT法研究上颌第一磨牙根管系统解剖形态

The morphological analysis of root canal system of maxillary first molars with micro-CT

目的使用显微CT研究上颌第一磨牙根管系统解剖形态。方法随机收集33颗上颌第一磨牙,使用显微CT扫描后重建根管系统。观察并记录各牙根根管形态和分支根管的发生数目、位置。记录各根管口位置并测量根管口间的距离和所成角度。在距离根尖1、2和3mm处进行虚拟切割,记录断面上分支根管暴露情况。结果上颌第一磨牙近颊根第二根管发生率为75.76%。近颊根发生分支根管为71.64%;近颊根分支根管发生率为72.73%。91.04%的分支根管发生于根尖1/3段,近颊根距根尖3mm处截面分支根管暴露率为12.12%。近颊根第一、第二根管口间的距离为(1.60±0.41)mm。结论上颌第一磨牙根管系统解剖形态复杂,近颊根根管形态存在较大解剖变异。

Objective To investigate the root canal system morphology of maxillary first molars with micro-CT. Methods Thirty-three maxillary first molars were randomly selected and scanned with micro-CT. After root canal reconstruction, canal morphology including numbers and locations of branch canals were recorded. Distance and angle among orifices were measured. Virtual cuttings were made at the level of 1mm, 2mm and 3mm to each root apex, and branch canal exposure was recorded. Results Incidence rate of the second mesiobuccal canal was 75.76%. 71.68% of the branch canals was in the mesiobuccal root. Incidence rate of branch canals in the mesiobuccal root was 72.73%. 91.04% of the branch canals was in the apical third, and the exposure rate of branch canal in the level of 3mm to the mesiobuccal apex was 12. 12%. The distance between the first and second mesionbuccal canal orifice was （ 1.60 ±0.41 ） mm. Conclusion Root canal morphology was complicated in the maxillary first molars and high anatomical variability was observed in the mesiobuccal root.