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Context: The significance of enamel etching has been well-researched and established. Limited literature is available comparing the enamel bond strengths of the two-step self-etch adhesive system and the newly introduced universal adhesive (UA) system with prior acid etching. Aims: The aim of the study was to evaluate and compare the microtensile bond strength (μTBS) of composite to enamel with and without 37% orthophosphoric acid pre-etching using a recently introduced UA and a two-step self-etch adhesive. Subjects and Methods: This in vitro , experimental study was conducted on 48 extracted human third molar teeth. Two enamel surface fragments were obtained per tooth, polished using 600-grit silicon carbide abrasive paper, and randomly divided into four groups-CLEARFIL SE BOND with and without acid pre-etching and G-Premio Bond with and without acid pre-etching. The samples were etched using 37% phosphoric acid gel for 30 s, followed by the bonding protocol. Composite resin blocks were built incrementally to a thickness of approximately 6 mm, and the restored samples were stored in distilled water for 24 h at 37°C. They were then sectioned, mounted, and subjected to a μTBS test using a universal testing machine. Statistical Analysis Used: Statistical analysis of the data was performed using one-way ANOVA and Tukey's post hoc test using SPSS software version 22.0. Results: Samples bonded with the UA subjected to prior acid etching protocol demonstrated the highest enamel μTBS. In contrast, those treated with the two-step self-etch adhesive without prior acid etching demonstrated the lowest enamel μTBS. Pre-etching with phosphoric acid significantly increased the enamel bond strength of both bonding agents, with the universal agent showing better results than the two-step adhesive system. Conclusions: Enamel etching with phosphoric acid significantly increases the bond strength of self-etch adhesives. UA with prior acid etching showed the maximum enamel μTBS. Two-step self-etch adhesive without prior acid etching yielded enamel μTBSs unacceptable for long-term, durable bonding. [ABSTRACT FROM AUTHOR]

Context: The lack of a suitable armamentarium to aid in the disinfection and handling of gutta-percha (GP) cones during obturation has been a common challenge amongst dentists. Aims: This study assessed the clinical usability of 'Vasundhara's (V) Transit GP' through a questionnaire-based survey. Settings and Design: This questionnaire-based study was conducted in Davanagere, Karnataka, in February 2021 for 4 months. Methods and Material: The design was 3D printed using a heat-resistant polypropylene material and named 'Vasundhara's Transit for Gutta Percha (V Transit GP)'. Eighteen postgraduate students participated in the study. Fourteen cases were done by each student, seven without and seven with the use of 'V Transit GP'. The GP cones, before obturation, were transferred to their respective canal slots containing 5.25% sodium hypochlorite for one minute and then transferred to their respective distilled water slots. The cones were dried with sterile gauze and taken for obturation. At the end of the procedure, a questionnaire was handed out, the responses were recorded, and the results were tabulated and analysed using Statistical Package for the Social Sciences (SPSS) version 22.0 software. Results: The results showed that without the use of 'V Transit GP', 84.2% of the dentists felt that the disinfection and handling of GP cones were difficult, whereas with the use of 'V Transit GP', 94.2% of the participants found it to be extremely easy. Conclusions: 'V Transit GP' proved to be an extremely efficient and user-friendly equipment for easy handling and disinfection of GP cones during obturation. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study was to assess, in vitro , the human pulp dissolution capacity of 500 ppm and 200 ppm of hypochlorous acid in comparison with 5.2% sodium hypochlorite (NaOCl)., Materials and Methods: Forty pulp tissue samples were standardized to a weight of 9 mg and divided into four groups according to the irrigating solution used: 5.25% NaOCl, 500 ppm hypochlorous acid, 200 ppm hypochlorous acid, and distilled water. Eppendorf tubes carrying 2 mL of the irrigants were taken and the pulp tissue samples were placed in the tubes for the specified time interval: Subgroup A: 30 minutes and subgroup B: 60 minutes. After the designated time interval, the solution from each sample tube was filtered using Whatman filter paper and left for drying overnight. The residual weight was calculated by filtration method. The mean dissolution time for each experimental group at the different time intervals was statistically analyzed., Results: Mean tissue dissolution increases with an increase in the time period. Approximately 5.25% NaOCl was most effective at both time intervals followed by 500-ppm hypochlorous acid at 60 minutes. Least amount of tissue dissolution was shown by 200-ppm of hypochlorous acid at 30 minutes. Distilled water did not show the ability to dissolve human pulp tissue., Conclusion: Within the limitations of the study, 5.25% NaOCl dissolved the pulp tissue most efficiently at both time intervals and both concentrations. Human pulp tissue dissolution by hypochlorous acid was found to gradually increase with time and with an increase in its concentration., Clinical Significance: With the basic information that hypochlorous acid does have the capacity to dissolve human pulp tissue, further research can be undertaken to assess methods to increase its efficiency. Sooner than later, hypochlorous acid may be able to completely replace the toxic NaOCl in clinical practice, as the irrigant of choice during root canal therapy.