中国人上颌第一恒磨牙根管解剖形态的显微CT研究

Micro-CT study on the root canal morphology of the maxillary first permanent molar in the Chinese population

目的:使用显微CT研究上颌第一恒磨牙的根管解剖形态。方法:对190颗分叉根上颌第一恒磨牙进行显微CT扫描,三维重建根管形态。对根管形态进行分类,记录副根管、根管环、管间交通支、根管峡区、MB2、根尖三角洲发生率;对根尖狭窄部进行分类;记录根尖孔的数目。结果:近颊根管2-2型多见(25.3%),远颊根管(83.2%)和腭根(92.1%)1-1型为主。近中颊根的副根管、管间交通支、根管峡区、根尖三角洲发生率均显著高于远颊根和腭根(P<0.05)。81.6%的近中颊根存在MB2。根尖狭窄发生率较低,最常见是单一缩窄型。80.5%近中颊根存在有2个以上的根尖孔,67.4%的远中颊根和70.5%的腭根只有1个根尖孔,三根之间的根尖孔数目存在统计学差异(P<0.05)。结论:上颌第一恒磨牙根管形态复杂多样,尤其是近中颊根,临床行根管治疗应防止遗漏根管,提高机械和化学清理的效果。

Objective:To study the root canal anatomy of maxillary first permanent molar with micro-computed tomography(micro-CT).Methods:Totally 190 maxillary first permanent molars with bifurcated roots were scanned by micro-CT,and the images of the root canal systems were reconstructed.The three-dimensional morphology of root canals was studied,and the incidence of accessory canal,root canal loops,intercanal communication,isthmuses,MB2,and apical delta were recorded.The apical constriction types were classified.The numbers of apical foramina were recorded.Results:25.3%of mesiobuccal root canals were type 2-2,and 83.2%.of distobuccal root canals and 92.1%palatal root canals were type 1-1.The incidences of accessory canals,intercanal communications,isthmus,and apical delta in mesiobuccal roots were significantly higher than those in distobuccal roots and palatal roots(P<0.05).MB2 was present in 81.6%of mesiobuccal roots.The incidence of apical constriction was low,and when present the most common type was the single constriction type.80.5%of mesiobuccal roots had more than two apical foramina,67.4%of distobuccal roots and 70.5%of palatal roots had only one apical foramen,and the number of apical foramina among the three roots was statistically different(P<0.05).Conclusion:The root canal of the maxillary first permanent molar is complex and diverse,especially in the mesiobuccal root.Clinical root canal treatment should focus on enhancing the effectiveness of both mechanical instrumentation and chemical disinfection.