The objective of this study is to evaluate, the apical transportation and centering ability in mesial mandibular root canals after biomechanical preparation with 3 different NiTi rotary systems.
Twenty seven freshly extracted human mandibular first molar teeth were collected from the outpatient clinic of Oral and Maxillofacial Department, Faculty of Dentistry, Cairo University. Teeth were decoronated and the distal root of each tooth was resected at the furcation level using a safe sided diamond disc under coolant. The working length was adjusted to be 16mm. A K-file size #15 was confirmed to fit to the full working length. Mesial roots were vertically mounted halfway in autopolymerizing acrylic resin. All roots were scanned using CBCT to detect canal shape before instrumentation.Teeth were then divided into three groups (n=9) according to the type of the rotary instruments used in the root canal preparation and irrigated with 2.5% sodium hypochlorite solution before instrumentation.(Trunatomy group, protaper next group and M-Pro group)
Post instrumentation tomograms were taken and the degree of canal transportation and centering ability ratio were calculated.
Data were analyzed using one-way ANOVA followed by Tukey's post hoc test for intergroup comparisons.The significance level was set at p < 0.05 within all tests.
Regarding canal transportation,there was a significant difference between different files with Trunatomy having significantly lower value than other files (p=0.014).
Regarding centering ability there was a significant difference between different files with M-pro having significantly lower value than other files (p < 0.001).