Effects of heating on bioceramic sealers: a scoping review of chemo-physical properties and clinical implications.

This scoping review aims to summarize current research to assess the impact of heating on the chemo-physical properties of bioceramic sealers. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Extension for Scoping Reviews guidelines, a comprehensive literature search was conducted in April 2024 across PubMed and Scopus databases. Inclusion criteria referred to all study types evaluating the effect of heating temperature on bioceramic sealers' properties, with no language or time restrictions applied. Studies were independently screened by two reviewers, and relevant data were extracted and synthesized qualitatively. Out of 91 initially identified studies, 19 met the eligibility criteria for inclusion in the qualitative synthesis. The selected studies ranged from 2014 to 2024 and comprised laboratory-based investigations. Various bioceramic sealers, including EndoSequence BC Sealer, BioRoot RCS, and TotalFill BC, were analyzed across different heating techniques. The findings revealed divergent responses of bioceramic sealers to heat, with some demonstrating stability while others exhibited alterations in properties such as flow, setting time, and chemical composition. The impact of heat on bioceramic sealers depends on the sealer's composition and laboratory setting. While some sealers are affected significantly, others remain stable. Clinicians should carefully consider these factors when bioceramic sealers are used with warm obturation techniques, but caution is needed as real-world conditions may vary. Integrating laboratory results with clinical evidence is essential for improving treatment efficacy and patient care.

The Role of Pecking Motion Depths in Dynamic Cyclic Fatigue Resistance: In Vitro Study.

OBJECTIVE: This is the first study evaluating the impact of different pecking motion depths on dynamic cyclic fatigue resistance of different endodontic instruments. METHODS: Four nickel-titanium systems (Hyflex EDM OneFile 25/. ∼; Rotate 25/0.6; Mtwo 25/0.6; Reciproc Blue R25) were tested. Forty instruments from each group were subjected to 4 different pecking movements to evaluate their cyclic fatigue resistance. The distances for the pecking motion were 3-mm forward and backward, 1-mm (3-mm forward and 2-mm backward), 2-mm (4-mm forward and 2-mm backward), and 3-mm (5-mm forward and 2-mm backward). Speeds were 100 and 200 mm/min for the descending and ascending motion, respectively. The times to fracture (TtF) in seconds were recorded for each instrument. Data were statistically analysed by using 2-way ANOVA and Bonferroni multiple comparison post hoc test (P < .05). RESULTS: All instruments had a significant increase in cyclic fatigue resistance during the forward dynamic motion compared with the axial continuous. Overall, the heat-treated instruments reported higher fatigue strength than the untreated files (P < .05). Reciproc Blue and Hyflex EDM showed higher TtF in the forward movements of 1-/2-mm and 2-mm (P < .05), respectively while Mtwo 25.06 and Rotate 25.06 in the forward movement of 3-mm (P < .05). CONCLUSIONS: Within the limits of this in vitro study, the pecking motion depths had varying impacts on the cyclic fatigue resistance of instruments. Reciproc Blue and Hyflex EDM performed significantly better with pecking motions of 1-and 2-mm. Improving endodontic instrument durability through specific pecking depths has the potential for improving clinical performance and reducing instrument failures.