Influence of Heat Treatment of Nickel-Titanium Rotary Endodontic Instruments on Apical Preparation: A Micro–Computed Tomographic Study

• Published in: Journal of endodontics Vol. 41; no. 12; pp. 2031 - 2035
• Main Authors: Almeida, Bernardo Corrêa de, DDS, MSc, Ormiga, Fabíola, DDS, MSc, DSc, de Araújo, Marcos César Pimenta, DDS, MSc, DSc, Lopes, Ricardo Tadeu, DSc, Barbosa Lima, Inayá Corrêa, DSc, dos Santos, Bernardo Camargo, DDS, MSc, Gusman, Heloisa, DDS, DSc
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.12.2015
• Subjects: Alloys; Canal transportation; Dental Alloys; Dental Pulp Cavity - anatomy & histology; Dental Pulp Cavity - diagnostic imaging; Dentistry; Endocrinology & Metabolism; heat treatment; Hot Temperature; Humans; Mandible; micro–computed tomography; Molar - anatomy & histology; Molar - diagnostic imaging; nickel-titanium instrument; Root Canal Preparation - instrumentation; X-Ray Microtomography; micro–computed tomography; Canal transportation; heat treatment; nickel-titanium instrument
• ISSN: 0099-2399; 1878-3554
• DOI: 10.1016/j.joen.2015.09.001

Abstract Introduction The aim of this study was to make a 3-dimensional comparison of the canal transportation and changes in apical geometry using micro–computed tomographic imaging after canal preparation with K3 (SybronEndo, Orange, CA) and K3XF (SybronEndo) file systems. Methods Twenty-eight mandibular molars were randomly divided into 2 groups according to the rotary system used in instrumentation: K3 or K3XF. The specimens were scanned by micro–computed tomographic imaging before and after instrumentation. Images before and after instrumentation from each group were compared with regard to canal volume, surface area, and structure model index (SMI) (paired t test, P  < .05). After instrumentation, the canals from each group were compared regarding the changes in volume, surface area, SMI, and canal transportation in the last 4 apical mm ( t test, P  < .05). Results Instrumentation with the 2 rotary systems significantly changed the canal volume, surface area, and SMI ( P  < .05). There were no significant differences between instrument types concerning these parameters ( P  > .05). There were no significant differences between the 2 groups with regard to canal transportation in the last 4 apical mm ( P  > .05). Conclusions Both rotary systems showed adequate canal preparations with reduced values of canal transportation. Heat treatment did not influence changes in root canal geometry in the apical region.