Comparison of shaping efficacy of 4 nickel-titanium single-file instru-ments in preparation of curved root canals
Aim:To compare the shaping efficacy of preparing curved root canals by 4 nickel-titanium single-file in-struments.Methods:The mesiobuccal canals of 64 extracted maxillary first molars were allocated into moderate bending group and severe bending group according to their curvature.Each group was randomly divided into 4 subgroups(n =8),the root canals were prepared with 4 nickel-titanium single-file instruments,WaveOne Gold,Reciproc Blue,M3-L and Fengdu V Blue,and named as WG group,RB group,M3 group,and VB group.The operation time was recorded,respectively.The off-set,the axial center rate and changes of bending angle were measured by cone-beam CT.Results:No instruments were de-formed or broken during the preparation process.There was no significant difference in preparation time among subgroups with the same degree of curvature(P>0.05).Among the severely curved root canals,the change of bending angle in M3 group was the smallest.The root canal offset of the 4 single-file instruments was less than 0.30 mm.At 3 mm from the api-cal,the root canal offset in the WG group was the largest,and at 5 mm from the apical,the root canal offset in the WG group was small and the axial center ratio was closest to 1.Conclusion:Although 4 nickel-titanium single-file instruments could maintain the original anatomical shape of the curved root canals well,WaveOne Gold has better center positioning ability,and M3-L is more advantageous in maintaining the curvature angle of the root canals.
万方数据
维普
