The effect of irrigation solution temperature and novel heat-treated rotary files on apical debris extrusion and canal preparation time.

This study aimed to compare apical debris extrusion and canal preparation time with ProTaper Gold (PTG) and ProTaper Ultimate (PTU) files at different temperatures. Mesio-buccal roots of 60 mandibular first molars were distributed into six groups depending on the file type (PTG, PTU) and irrigation solution temperature (20, 37, 45°C). During instrumentation, extruded debris were collected and weighed to measure the mass in milligrams. The canal preparation time was recorded in seconds. ANOVA followed by Bonferroni post-hoc tests were used for analysis. The amount of debris extrusion was significantly higher in PTU, which was affected by the irrigation solution temperature (p < 0.05). The difference in canal preparation time was not significant between the two file systems, however, it was significant between the different temperatures (p = 0.001). Both file systems had shorter canal preparation times at 20°C. The irrigation solution temperature could influence the debris extrusion and time of canal preparation.

A CBCT based cross sectional study on the prevalence and anatomical feature of C shaped molar among Jordanian.

The prevalence and anatomical features of C-Shaped Mandibular Second Molars (MSMs) are rarely studied in Jordanian sub-population. This study then took a part to evaluate the prevalence of C-shaped in MSMs using cone-beam computed tomography (CBCT) in the Jordanian sub-population. It used a cross-sectional design and three thousand scans collected over eight years between 2011 and 2019. The data were then reviewed for whether they were fully formed of MSMs. A total of 2037 cases that had 2845 MSMs were evaluated to identify C-shaped canals at coronal, middle, and apical sites. An oblique slicing module perpendicular to the long axis of MSMs was used to evaluate the teeth. The type and frequency of C-shaped canals, as well as the correlations between sex and side (right/left) and between sex and groove direction (buccal/lingual) were measured using the chi-square test on SPSS software at the significance level of 95%. A total of 342 teeth of 243 patients were C-shaped molars, which comprised 12% of the patient's teeth and 99 of them as a bilateral C-shaped canal with mean age of 40 years and sex ratio of 2:1 between female and male. With the limitations of this study, the lingual groove and type 3 were the most common properties of MSM. Besides, the Jordanian population mostly had C-shaped canals.

Evaluating In Vitro Performance of Novel Nickel-Titanium Rotary System (TruNatomy) Based on Debris Extrusion and Preparation Time from Severely Curved Canals.

INTRODUCTION: This laboratory-based study aimed to investigate the quantitative amount of apically extruded debris from severely curved root canals and the preparation time for the novel rotary system TruNatomy (TN; Dentsply Sirona, Charlotte, NC) compared with Reciproc Blue (RCB; VDW Dental, Munich, Germany), HyFlex (HyFlex Controlled Memory [HCM; Coltene/Whaledent, Altstatten, Switzerland] and HyFlex EDM [HEDM, Coltene/Whaledent]), and ProTaper Next (PTN; Dentsply Maillefer, Ballaigues, Switzerland) rotary systems. METHODS: One hundred mandibular molar human teeth with severe curvature of the mesiobuccal canal (25°-45°) were included in the present study. The specimens were randomly distributed into 5 balanced groups (n = 20): TN, RCB, HCM, PTN, and HEDM. The amount of extruded debris for each group during instrumentation at body temperature was collected in an Eppendorf tube. After desiccation, the mean debris weights for each group were calculated. The total preparation time for each group was also recorded. Data were statistically analyzed using the Kruskal-Wallis test at a significance level of P < .05. RESULTS: The HCM and HEDM groups extruded a significantly higher amount of debris than the other tested groups (P < .001). TN extruded the least amount of debris, but it was not significantly different compared with the RCB and PTN groups (P > .05). In terms of preparation time, the TN group did not show any significant difference compared with the other groups. CONCLUSIONS: All instrumentation systems extruded debris. TN was among the groups that produced the lowest amount of apically extruded debris that is clinically acceptable. The amount of apically extruded debris using the TN system was equal to 2 popular systems and statistically significantly less than 2 other popular systems studied.