CBCT应用于下颌第一磨牙独立远中舌根根管增龄性变化的研究

Study of Age-Related Changes of Distal-Lingual Root Canal of Mandibular First Molar by CBCT

目的利用锥形束CT(cone-beam computed tomography,CBCT)研究不同年龄段的下颌第一磨牙独立远中舌根的根管,探讨其增龄性变化,以期为临床根管治疗有所指导。方法选取200例具有独立远中舌根的门诊患者,其中年龄≤40岁者(≤40岁组)100例,年龄>40岁者(>40岁组)100例。2组均进行CBCT扫描,图像分析包括:1)远中舌根根管口与远中颊根根管口间距(DL-DB)的测量;2)近中舌根根管口与远中舌根根管口间距(ML-DL)的测量;3)远舌根管的近远中向及颊舌向弯曲度及弯曲部位的判定。结果 1)DL-DB间距:≤40岁组为( 3.20±0.85)mm,>40岁组为(3.05±0.76)mm,2组比较差异有统计学意义( P <0.05)。2)ML-DL间距:≤40岁组为(3.74±0.44)mm,>40岁组为(3.69±0.52)mm,2组比较差异无统计学意义( P >0.05)。3)远舌根管颊舌向弯曲度:≤40岁组为(35.5±6.7)°,>40岁组为(37.6±7.2)°,2组比较差异有统计学意义( P <0.05);远舌根管近远中向弯曲度:≤40岁组为(9.1±8.2)°,>40岁组为(9.7±6.1)°,2组比较差异无统计学意义( P >0.05);≤40岁组和>40岁组弯曲部位均绝大多数位于根中1/3。结论下颌第一磨牙随着年龄的增长,DL和DB根管口间距离会缩小,远舌根管弯曲度会增大。

Objective To investigate the age-related changes of distal-lingual root canal of mandibular first molar using cone-beam computed tomography(CBCT),and to provide guidance for clinical root canal treatment. Methods CBCT scanning was performed in 200 outpatients with independent distal-lingual root(100 patients aged≤40 years and 100 patients aged>40 years) to measure the distance between distal-lingual orifice and distal-buccal orifice(DL-DB),distance between mesial-lingual orifice and distal-lingual orifice(ML-DL) and curvature of root canal. Results The DL-DB distance,ML-DL distance,curvature towards buccal-lingual direction and curvature towards mesial-lingual direction were respectively(3.20±0.85)mm,(3.74±0.44)mm,(35.5± 6.7)° and (9.1±8.2)° in patients ≤40 year old,and (3.05±0.76)mm,(3.69±0.52)mm,(37.6± 7.2)° and (9.7±6.1)° in patients >40 year old.There were significant differences in DL-DB distance and curvature towards buccal-lingual direction between the two groups( P <0.05).Most of the curves were located at 1/3 of the root. Conclusion The DL-DB distance decreases and distal-lingual root canal curvature increases with age in mandibular first molar.