Comparison of the dentinal microcracks after the root canal preparation by four kinds of Ni-Ti rotary instruments
WANG Quan-yu
BI Wan-ting
XUE Ming
Abstract：Objective To compare the differences in the dentinal microcracks after the root canal preparation (RCP)by four kinds of Ni-Ti rotary instruments in vitro,so as to provide references for clinicians in the selection of instruments and methods during RCP.Methods A total of 125 complet incisors extracted from Jan.to Oct.of 2016 were selected as the research subjects,and they were divided into 5 groups on average according to the random table methed.Four kinds of Ni-Ti rotary instrument (Group N:ProTaper Next,Group W:WaveOne Gold,Group M:M3-Pro,Group P:ProTaper Universal)were respectively used for RCP,the remaining group being as the control group (Group C).The roots were cut horizontally at 3 mm,6 mm and 9 mm from the apices,and existence of dentinal microcracks were observed and recorded under the microscope.Results No dentinal microcracks were found in the control group without RCP.The number of teeth with microcracks in Group P was obviously higher than that in Group N,Group W and Group M.The total number of teeth with microcracks from the apical 3 mm was obviously higher than that from the apical 6 mm and 9 mm in all the preparation groups.Conclusion Dentinal microcracks may be caused during RCP using Ni-Ti instruments;the dentinal microcracks produced at 3 mm from the apical tip were significantly more than those at 6 mm and 9 mm;compared to ProTaper Universal,ProTaper Next,WaveOne Gold and M3-Pro can significantly reduce the incidence of dentinal microcracks.
Keywords：Ni-Ti instrumentroot canal preparationdentinal microcrackvertical root fracture
Publication Date：2018-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：5( 32-36 )