No abstract

Background:Antibacterial activity is one of the important characteristics of an ideal root canal sealer. The aim of this study was to investigate the antibacterial activity of five different sealers against Enterococcus faecalis using two different methods.Materials and Methods:The mineral trioxide aggregate (MTA) Fillapex, Tg-sealer, Endomethasone, AH-26, and RoekoSeal sealers were placed into the brain heart infusion (BHI) culture medium containing E. faecalis (PTCC1393). The diameter of the bacterial zone of inhibition was measured. In the direct contact test, a suspension containing grinded set sealers and E. faecalis bacteria was cultured in BHI after 6, 15, and 60 min. The number of colonies in milliliter was calculated. Data were subjected to one-way ANOVA and Tukey's multiple comparisons test (P < 0.05).Results:In the agar diffusion test, Endomethasone had the highest antibacterial activity against E. faecalis compared to other sealers (P < 0.001). In the direct test, the antibacterial effect of MTA Fillapex was significantly higher than that of all other sealers (P < 0.001).Conclusion:The technique and components of the tested sealers affect the antibacterial activity results. This study showed that all of sealers had antimicrobial effect.

Background: The purpose of this study was to evaluate the prevalence of middle mesial canal in mandibular first molars using cone-beam computed tomography (CBCT). Materials and Methods: In this descriptive study, a total of 768 radiographs of mandibular first molars, 384 for males and 384 for females, taken at a private radiology center in Isfahan, were assessed for the presence of middle mesial canal based on the gender of the patients. All samples had been prepared by one CBCT machine. The images were evaluated by endodontists and radiologists. Then, the morphology of first molar mesial root canals was assessed by Vertucci classification, and the obtained results were analyzed by SPSS software using a Chi-square test. The comparison was considered statistically significant at P < 0.05. Results: Twenty-four samples (3.13%) had a middle mesial canal. The prevalence rates of the middle mesial canal in the females and males were found to be 9 and 15 (2.35% vs. 3.92%), respectively, indicating no statistically significant difference (P = 0.21). Of 24 teeth with middle mesial canal, 17 samples (70.8%) were of Type XII and 7 samples (29.2%) were of Type VIII. There was no statistically significant difference between genders with regard to the prevalence of different types of middle mesial canals (P = 0.19). Conclusion: The prevalence of the middle mesial canal was rather low in this study, and it is necessary to detect additional canals in the patients under root canal treatment.

No abstract

No abstract