OBJECTIVE: The aim of this study was to determine the conicity of the root canals of the upper and lower primary second molars using nanotomography (nCT).
METHODS: An in vitro study was performed using nine primary second molars, both upper and lower, subjected to nCT. Comparisons between the diameters of root canals were performed between the thirds (cervical-D0, middle-D5, and apical-D7). The conicity (%) was determined for each root canal from cervical to apical. Data were statistically analyzed with a significance level of 5%.
RESULTS: The conicity ranged from 2% to 8% for the upper primary second molars. Significant differences in root canal diameter between the thirds (D0, D5, and D7 points) were observed in the mesio- and distobuccal roots (p < .05), but not in the palatal roots (p > .05). For the lower primary second molars, the conicity ranged from 2% to 17%, as well as significant differences in root canal diameter between the thirds (D0, D5, and D7 points) were observed in all roots (distal, mesiobuccal, and mesiolingual; p < .05).
CONCLUSIONS: The conicity of the upper primary second molars was different from that of the lower ones, which showed a greater variability.
目的:本研究的目的是使用纳米技术(nCT)确定上下主第二磨牙根管的锥度。
方法:使用九颗初级第二磨牙进行了一项体外研究,上部和下部,进行NCT。在三分之二(子宫颈D0,中D5和根尖D7)之间进行了根管直径之间的比较。确定从宫颈到根尖的每个根管的锥度(%)。对数据进行统计学分析,显著性水平为5%。
结果:对于上初级第二磨牙,锥度范围为2%至8%。在近侧根和远侧根(D0,D5和D7点)之间观察到根管直径的显着差异(p<0.05),但不在腭根中(p>.05)。对于下颌第二磨牙,锥度范围从2%到17%,在所有根(远端,近颊,和中舌;p<.05)。
结论:上初级第二磨牙的锥度与下初级第二磨牙的锥度不同,表现出更大的变异性。