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Aims:The purpose of this study was to compare the sealing ability of Mineral Trioxide Aggregate (MTA) and Glass Ionomer Cement (GIC) when used over gutta-percha as intracanal sealing materials. The study also evaluated the sealing ability of Zinc oxide eugenol (ZOE) cement and Acroseal sealer.Materials and Methods:Teeth were obturated with gutta-percha using sealer ZOE (group A, C, D) and Acroseal (group B). The groups were further divided into 2 subgroups (15 premolars each) on the basis of intracanal sealing material used: GIC subgroups (A1, B1) and MTA in subgroups (A2, B2). The clearing technique was used in this study for leakage evaluation. Seventy mandibular premolars were prepared using step-back technique and divided into experimental groups A and B (30 premolars each) and the positive and negative control groups C and D (5 premolars each).Statistical analysis used:Coronal microleakage was determined under stereomicroscope using 15X magnification. Data was statistically analyzed using one-way ANOVA followed by Post-Hoc Multiple comparison (Bonferroni).Results:MTA group leaked significantly less than GIC group (P < 0.05). Acroseal exhibited better sealing ability than ZOE sealer. Teeth with no intracanal barrier showed almost complete leakage.Conclusions:MTA may be preferred over GIC as an intracanal barrier.

Study was planned to evaluate the efficacy of commonly used disinfectants and to study qualitatively and quantitatively the persistence of microflora on the untreated (control group) and the disinfected impression surface after 24 h. Disinfectant systems used were immersion systems like glutaraldehyde, sodium hypochlorite and the ultraviolet chamber. The effect of disinfectant on most commonly used Indian impression materials was carried out in this study and results compared with the most commonly used foreign brands for irreversible hydrocolloid and addition silicone. Impressions were made of 25 healthy volunteers. These were disinfected and incubated in an incubator for 24 h at 37°C for aerobic organisms. The inoculation in nutrient media was done to test the viability of microorganisms that can persist after rinsing and disinfection of the impression surface. The colony forming units were counted and compared with that of control group. Control group of all the impression material samples showed growth of Streptococcus viridans, Diphtheroids, Streptococcus pneumoniae to a greater extent. The growth of Candida albicans, Pseudomonas aerugenosa and Staphyloccus albus was present in all the groups but to a lesser extent. The persistence of the microflora on the impression surface of both the studied brands was similar but the concentration of organisms in the alginate control group was two folds as compared to addition silicone group. Use of ultraviolet chamber gave better results compared to the studied immersion systems. All the disinfection systems were effective in reducing the microbial load with ultraviolet chamber as the most effective.

Evaluated materials can be safely disinfected with sodium hypochlorite and ultraviolet chamber. Addition silicone of native origin is at par with impression materials from developed countries but same cannot be said about alginate.

Background: On account of the pandemic SARS-CoV-2 (COVID-19), education in higher institutes was strongly affected and they were shut down. The education shifted from “face-to-face” learning to online learning in the dental universities. The aim of this study was to assess the students' perspective on the implementation of online learning due to COVID-19, using a questionnaire-based survey in India. Materials and Methods: The authors sent out an electronic survey to the undergraduate dental students from October 17, 2020 to October 25, 2020. The online questionnaire had a combination of multiple-choice, Likert scale, and open-ended questions which gave insight into the demographics, access to technological sources, didactic benefit, study habits, perceived issues with e-learning, conduction of examinations during the pandemic period, and their mental health. Students were also asked for their views on the inclusion of online learning in the future curriculum. Qualitative data was expressed as number and percentage. A comparison was performed using Chi-square test. Kruskal-Wallis test was done for Likert scale questions and Bonferroni test was used for post hoc comparisons. Results: Among 2319 dental students, 63.9% exclusively used smartphones and 8.5% used laptops for classes. The rest of the students used both devices. To access online resources, about 2262 (97.5%) had Internet connection. Only 943 students (40.7%) did not encounter any difficulty while engaging in online learning. About 1466 students (63.2%) appeared for examinations. About 1261 students appeared offline for both theory and practical examinations. Fifty-five percent of the participants felt offline examinations to be a better alternative. About 69.6% of students preferred “face-to-face” learning instead of solely online learning. Nearly 19.4% of students wanted online education to be continued, while 28.5% wanted to keep both offline and online courses in the future curriculum. Most frequently encountered problems were difficulty in adjusting to new learning styles, having to perform responsibilities at home, and poor communication between educators and learners. Conclusion: Students showed a little reticent attitude towards on the implementation of online learning and were hopeful of engaging in online learning after improvisation in the future curriculum.