Dentinal Microcrack Formation During Root Canal Treatment with Mtwo Instruments and MicroSeal Filling Technique

Objective:The purpose of this study was to evaluate dentinal microcrack formation during root canal treatment using Mtwo NiTi rotary instruments and MicroSeal filling technique.Materials and Methods:Forty-five single-rooted teeth were selected for the present study and divided into 3 different groups ( n = 15): Group 1, in which root canals were instrumented with Mtwo rotary files; Group 2, in which root canals were instrumented with Mtwo rotary files and filled using the MicroSeal technique; and Group 3, that acts as a control group in which no instrumentation nor obturation were performed. Then, roots were sectioned 3 mm, 6 mm, and 9 mm from the apex and the cut surface has been observed under a stereomicroscope to check for the presence or absence of dentinal microcracks. Number of dentinal microcracks was registered for each group at different levels and data were statistically analyzed using the Chi-square test with a level of significance set at P < .05.Results:No statistically significant differences were registered among groups ( P < .05). No microcracks were detected in Groups 1 and 3, while two dentinal microcracks were registered in Group 2.Conclusions:Mtwo rotary instruments and the MicroSeal root canal filling technique did not significantly induce dentinal microcrack formation.