Comparison of Cyclic Fatigue Resistance of Novel TruNatomy Files with Conventional Endodontic Files: An In Vitro SEM Study.

AIM AND OBJECTIVE: To compare and analyze the cyclic fatigue resistance of novel TruNatomy files against the conventionally used rotary files and reciprocating files in a simulated canal system with curvatures in the middle, apical portions root, and S-shaped canal employing scanning electron microscopy. MATERIALS AND METHODS: Endodontic files tested in the study include ProTaper, HyFlex EDM, Reciproc blue, and TruNatomy files operated in a simulated root canal system. A total of 96 files were employed in this study. They were categorized into four groups. Group 1 employed 24 TruNatomy files, group 2 employed 24 ProTaper gold files, group 3 employed 24 HyFlex EDM files, and group 4 employed 24 Reciproc blue files. All the groups employed eight files each under three subgroups namely A, B, and C representing middle, apical, and double curvatures, respectively. Artificial grooves were incorporated in the stainless steel blocks having three different curvatures. All the file systems were operated with a torque-controlled electric motor. The files were engaged in the artificial canal until the occurrence of fracture. The time required for the fracture was noted. Length of fractured tip was measured using the digital Vernier caliper. The number of cycles of failure (NCF) was calculated. The fractured parts were subjected to scanning electron microscope to analyze the mode of fracture. RESULTS: TruNatomy files had the highest mean NCF values of 588.01 in middle curvature, 1,321 in apical curvature, and 642.5 in S-shaped curvature HyFlex EDM and Reciproc blue file system exhibited comparable cyclic fatigue resistance among them. ProTaper gold file system exhibited least mean NCF values of 158.13 in the middle, 196.5 in the apical curvature, and 116.88 in the S-shaped canal system. Middle portion fractured first than the apical curvature. The mean length of fractured segments was found to be insignificant among the experimental study groups tested. CONCLUSION: All the file systems employed in the study had good cyclic fatigue resistance while TruNatomy files had the highest cyclic fatigue resistance while HyFlex EDM and Reciproc blue had comparable fatigue resistance. ProTaper gold file system had the least fatigue resistance at different radius of curvature in the simulated canal system in the apical and middle portions and S-shaped root canal. CLINICAL SIGNIFICANCE: The selection of file systems in cleaning and shaping protocols is an enigma to the endodontics. This in vitro study explored the selection protocols for the execution of root canal preparation. Heat treatment of nickel-titanium (NiTi) endodontic files had improved the cyclic fatigue résistance significantly enhancing the clinical life of file systems.

Comparative Evaluation of Antimicrobial Efficacy of Toothpastes Containing Probiotic and Neem as Primary Ingredient on Salivary Streptococcus mutans in Melmaruvathur Population: An In Vivo Study.

AIM: This in vivo study was designed to compare the antimicrobial effect of toothpastes containing probiotics and neem on Streptococcus mutans in 18-30-year-old patients in Melmaruvathur population. MATERIALS AND METHODS: The study consisted of 60 patients who were randomly divided into two groups of 30 each. Group I received probiotic-based toothpaste (PerioBiotic), whereas Group II received neem-based toothpaste (Babool) as a preventive measure protocols to control the incidence and prevalence of dental caries. STUDY DESIGN PROTOCOLS: Participants were instructed to use the dentifrice selected for the study, two times a day for 60 days. Tests were performed on the saliva samples at the beginning of the study, 0 day, 15th day, 30th day, and 60th day following the use of toothpaste. The Statistical Package for the Social Sciences (SPSS-25) software, version, and Chi-square and one-way analysis of variance were used for data analysis. RESULTS: The toothpastes containing neem and probiotics as primary ingredients were efficient in reducing the number of bacterial count when comparing the baseline data with the 60 days data in both the groups as a therapeutic regimen. Intragroup values showed reduction in the number of bacterial count in both the groups in a gradual manner, whereas the intergroup values between the toothpaste showed no statistically significant difference in the bacterial count, and both toothpastes were efficient in reducing the bacterial count. CONCLUSION: This study reveals the influence of probiotics and neem on salivary S. mutans levels. The results revealed that neem-based and probiotic-based toothpaste, which were tested in this study, showed comparable antibacterial activity against the S. mutans. The neem-based toothpaste showed promising and good antimicrobial activity and reduced the level of bacterial count, which can be attributed to the presence of secondary metabolites, such as flavonoids, alkaloids, lectins, and polyphenols, as its active components. The effect of each component against the S. mutans needs to be quantified in further studies, and within the limitation of this short study, it can be considered as a better choice than commercially available toothpaste, which predominantly has chemicals as active ingredients, which in turn can compromise the safety aspects in the patients when used for controlling the dental caries for a longer duration.