基于CBCT的昆明地区人群上颌磨牙MB2根管特征

Root Canal Characteristics of Maxillary Molars MB2 in Kunming Population Based on Cone-beam Computed Tomography

目的回顾性分析来自昆明人群上颌第1和第2磨牙根管系统,尤其是近颊根第2根管的发生率及其根管类型规律。方法收集云南省第一人民医院358名患者总共1279颗上颌第1和第2磨牙锥形束CT(cone-beam CT,CBCT)资料,根据性别、牙位和年龄分组,分析MB2发生率、根管类型构成及根管口间距,研究MB2与MB1-P/DB-P比值的相关性。结果上颌第1磨牙MB2平均发生率为86.51%,不同年龄组17~19岁组最低(70.0%,P<0.05),其他3组间无显著性差异(分别为88.61%、87.39%、79.75%,P>0.05),MB2根管类型分别为Ⅱ型15.5%、Ⅲ型6.1%、Ⅳ型64.6%、Ⅴ型13.7%。上颌第2磨牙MB2平均发生率为52.05%,不同年龄组间无显著性差异(分别为40.00%、51.08%、52.44%、59.38%,P>0.05),MB2根管类型分别为Ⅱ型17.3%、Ⅲ型7.3%、Ⅳ型50.0%、Ⅴ型25.4%。上颌第1磨牙MB2与MB1距离为(1.70±0.72)mm,与垂线距离为(0.78±0.49)mm,MB1-P与DB-P比值分别为1.28±0.08(有MB2)和1.23±0.02(无MB2)。结论昆明人群上颌第1和第2磨牙MB2发生率较高,IV型常见,MB1-P与DB-P比值有助于术前明确MB2的有无,提高根管治疗的成功率。

Objective To investigate the characteristics of root canals of maxillary first and second molars in Kunming population,especially the second mesiobuccal(MB2)canals.Methods Cone-beam computed tomographic(CBCT)technology was used to analyze a total of 1279 maxillary first and second molars from 358 patients in our hospital.The root number,root canal classification,presence and location of MB2,distribution of the main root canal orifices were explored.Results The incidence of MB2 in maxillary first molars in Kunming population was 86.51%.The incidence of MB2 in group 17-19 age group behaved much lower(70.0%,P<0.05)and there were no significant differences among the other three groups(88.61%,87.39%and 79.75%,respectively,P>0.05).The distribution of MB2 was:typeⅡ15.5%,typeⅢ6.1%,typeⅣ64.6%and typeⅤ13.7%.The incidence of MB2 in maxillary second molars was 52.05%.There were no significant differences among all the four age groups(40.00%,51.08%,52.44%and 59.38%,respectively,P>0.05).The distribution of MB2 were typeⅡ17.3%,typeⅢ7.3%,typeⅣ50.0%and typeⅤ25.4%.The distance from MB2 to MB1 was 1.70±0.72 mm and that to vertical line was 0.78±0.49 mm.The ratios of the distance between the first mesiobuccal and palatal canal orifices(MB1-P)to that between the distobuccal and palatal canal orifices(DB-P)were 1.28±0.08(with MB2 present)and 1.23±0.02(MB2 absent).Conclusion MB2 root canal in maxillary molars in Kunming population occur with high incidence and most of them behave as type IV.The ratio of MB1-P to DB-P will help to define the presence of MB2 root canal and improve the success rate of root canal treatment.