Micro-CT evaluation of mesial canals preparation performed by two rotary NiTi systems in mandibular molars

Marcelo Haas Villas Bôas, Rodrigo Ricci Vivan, Marcela Milanezi De Almeida, Marco Antonio Hungaro Duarte, Norberti Bernardineli

Objective: To evaluate the preparation quality and wear of the mesial and furcal walls by microCT, regarding the instrumentation of the mesial canals of mandibular molars. Methods: Thirty extracted human mandibular molars were scanned with microCT. The parameters analyzed of the images were: maintenance of the root canal centralization, extension and direction of the instrumentation deviation, quantity of dentin removed, minimal thickness of remaining dentin and the apical and total volumes before and after instrumentation. The teeth were divided into three groups (n = 10): Group 1: ProTaper Rotary instrumentation until F2; Group 2: Twisted file Rotary instrumentation with 25/.08 instrument; Group 3: Manual instrumentation (control). Results: There were no significant differences (p > 0.05) between the Rotary systems in relation to the instrumentation deviation. The cervical third presented the greatest quantity of instrumentation deviation when compared to the apical levels, and less quantity of remaining dentin, especially for danger zone. The systems wore more dentin in the furcal walls of the middle and cervical thirds. There were no differences between the groups regarding the quantity of dentin in the apical third. The apical and total volumes did not significantly increase after the preparation with the instrumentation in this study. Conclusion: The NiTi Rotary systems evaluated did not significantly increase the apical and total volumes of the root canals. The greatest instrumentation deviation occurred in the middle and cervical thirds for all the systems analyzed. For all groups analyzed, the quantity of remaining dentin was significantly reduced in the furcal direction of the middle and cervical thirds.

Keywords: Root canal preparation. X-ray microtomography. Endodontics. Molar.

How to cite: Villas Bôas MH, Vivan RR, Almeida MM, Duarte MAH, Bernardineli N. Micro-CT evaluation of mesial canals preparation performed by two rotary NiTi systems in mandibular molars. Dental Press Endod. 2016 Sept- Dec;6(3):33-40. DOI: http://dx.doi.org/10.14436/2358-2545.6.3.033-040.oar

Friday, September 22, 2017 17:29