论文部分内容阅读
目的:通过Micro-CT探寻上颌磨牙近中弯曲根管终末预备宽度与产生根尖偏移量间的关系。方法:收集40颗离体上颌第一磨牙,使用iRaCe镍钛器械对近中颊侧根管进行根管预备,分别至根尖宽度.04/25#、.04/30#、.04/35#、.04/40#(n=10),使用5.25%Na OCl+17%EDTA冲洗根管,在根管预备前后分别进行Micro-CT扫描,通过图像分析距根尖3、6、9 mm的根管偏移量和轴中心率。结果:平均根管偏移量A组为(0.10±0.07)mm,B组为(0.09±0.06)mm,C组为(0.12±0.14)mm,D组为(0.13±0.12)mm。平均轴中心率A组为0.54±0.23,B组为0.37±0.20,C组为0.56±0.25,D组为0.47±0.27,各组间平均偏移量和轴中心率无显著性差异(P>0.05)。A组、D组根尖3 mm和9 mm处的根管偏移量有显著性差异(P<0.05),其余组间均无差异。根尖3 mm处4组间根管偏移量、轴中心率差异无统计学意议(P>0.05)。结论:终末预备宽度与根管偏移量和轴中心率并无显著性差异,即使是.04/40#的iRaCe器械预备磨牙弯曲根管时产生的根管偏移量也较小,有良好的中心定位能力,在临床上可安全使用。
OBJECTIVE: To investigate the relationship between the preparation width of proximal root canal root canal preparation and the apical offset by using Micro-CT. Methods: 40 maxillary first molars were collected, and the proximal and middle buccal root canals were prepared by root canal preparation using iRaCe NiTi instruments, respectively, to the apex width #, .04 / 40 # (n = 10). The root canal was rinsed with 5.25% Na OCl + 17% EDTA. Micro-CT scan was performed before and after root canal preparation. Root canal offset and axial center rate. Results: The mean root canal offset was (0.10 ± 0.07) mm in group A, (0.09 ± 0.06) mm in group B, (0.12 ± 0.14) mm in group C and (0.13 ± 0.12) mm in group D, respectively. The mean axial center rate was 0.54 ± 0.23 in group A, 0.37 ± 0.20 in group B, 0.56 ± 0.25 in group C, and 0.47 ± 0.27 in group D. There was no significant difference in mean offsets and axial center rates between groups (P> 0.05). There was significant difference (P <0.05) in root canal offset between the apical 3 and 9 mm in group A and group D, and there was no difference in other groups. Root apical 3 mm at the 4 groups of canal offset, axial center rate difference was not statistically significant (P> 0.05). CONCLUSION: There is no significant difference between the final preparation width and the root canal offset and axial center rate. Even the iRaCe premolar teeth of .04 / 40 # Good center positioning ability, can be safely used clinically.