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INTRODUCTION: The purpose of this study was to assess the antifungal activity of silver nanoparticles (AgNPs) in combination with calcium hydroxide (Ca(OH)2) against Candida albicans (C. albicans). METHODS: AgNPs was mixed with pure Ca(OH)2 powder in an aqueous base. A standard suspension (1 × 108 bacterial cells/mL) of C. albicans was prepared in a 96-well plate and incubated on shaker at 37 °C in 100% humidity to allow fungal biofilm formation in infected dentin slices (n = 98). The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of AgNPs alone or with Ca(OH)2 were determined. The samples were separately placed in 24-well tissue culture plates and divided into three experimental groups (0.03, 0.04, and 0.06) and three control groups; negative (saline) and positive chlorhexidine gel and Ca(OH)2. Quantitative measurements of fungal activity by XTT colorimetric assay and qualitative measurements using confocal laser microscopy and scanning electron microscopy were performed. RESULTS: The cell viability of C. albicans in the experimental groups was significantly reduced compared to the negative control group. The combination of (AgNPs (0.04%) and Ca(OH)2) was the most potent against C. albicans. CONCLUSIONS: The findings demonstrated that combining silver nanoparticles with Ca(OH)2 was more effective against C. albicans biofilm compared to Ca(OH)2 alone, suggesting a combing effect.
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OBJECTIVE: The aim of this ambispective cohort study was to examine the effect of instructional methods on dental students' performance in a preclinical endodontic course. Two cohorts of undergraduate students were included. The pre-pandemic (retrospective) cohort, which had been taught via traditional instruction (live lecture and live demonstration), and the pandemic (prospective) cohort group, which had been taught via a blended learning approach (online/video recorded lecture and video demonstration, combined with practical training in the simulation laboratory). METHODS: A total of 263 dental students' competencies and written exam results were reviewed, with 137 students from the traditional and 126 from the blended learning groups. Students' performances in the competency practical and written exams for both groups were compared. Additionally, a post-course survey was designed to explore the students' perceptions of blended learning and was sent to the blended learning cohort. RESULTS: There was a statistically significant difference between both groups in students' weekly practical project scores. The average score for females was significantly higher than that of males. However, their practical competency exam scores were comparable. On the other hand, the written exam scores were significantly higher in the blended than in the traditional group, with females demonstrating significantly higher written exam scores compared to males (p < 0.001). CONCLUSION: Blended learning is an effective teaching method for preclinical endodontic courses. It could be more useful than traditional learning methods for the course's theoretical content. Additionally, the students preferred to continue learning using this model.
