The impact of coronavirus disease 2019 pandemic on dental school assessments - Current status and future perspectives.

PURPOSE: To evaluate course directors' feedback on the assessment methods used during the coronavirus disease 2019 (COVID-19) pandemic and identify effective approaches for future assessments in dental education. METHODS: Course directors at the US dental schools were surveyed for changes in assessments implemented during the early stages of the pandemic (March-July 2020) using the Qualtrics platform. The survey questions addressed assessment methods utilized in didactic, preclinical, and clinical arenas pre-COVID-19 (before March 2020) and during the early phase of the pandemic (between March and July 2020) and identified any sustained changes in assessments post-COVID-19. Of the 295 responses for the type of courses directed, 48%, 22%, and 30% responses were for didactic, pre-clinical, and clinical assessments, respectively. Chi-square tests and 95% confidence intervals were used to assess quantitative differences. RESULTS: Computer-based un-proctored and remote- proctored assessments increased whereas paper-based in-person proctored assessments decreased during an early pandemic. For pre-clinical and clinical courses, objective-structured clinical exams and case-based assessments increased whereas, for didactic courses, the number of presentations, short-answer, and multiple-choice questions-based assessments increased. Specimen-based assessments and patient-based encounters decreased significantly in didactic and clinical courses, respectively. Manikin-based exams increased in clinical but not in pre-clinical courses. Survey respondents disagreed that alternative assessments helped students learn better, resulted in better course evaluations, or were an equivalent replacement for pre-COVID-19 assessments. Interestingly, 49% of respondents indicated a likelihood of continuing alternative assessments whereas 36% were unlikely and 15% were neutral. CONCLUSIONS: A combination of effective pre-pandemic and innovative alternative assessments developed during the pandemic may be the new normal in the dental education curriculum.

Comparative evaluation of intermediate solutions in prevention of brown precipitate formed from sodium hypochlorite and chlorhexidine gluconate.

OBJECTIVES: To evaluate intermediate treatments between sodium hypochlorite and chlorhexidine gluconate irrigations for the prevention of a toxic brown precipitate in root canal therapy. MATERIALS AND METHODS: Thirty-nine premolars were irrigated with 6% sodium hypochlorite and divided into either: No intermediate treatment; Dry paper points; three different irrigations with 17% ethylenediaminetetraacetic acid, deionized water, or 5% sodium thiosulfate. 2% chlorhexidine gluconate was the final irrigant in all groups. Sectioned teeth were analyzed for brown precipitate intensity and area using stereomicroscopy and components related to para-chloroaniline using Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS). RESULTS: Stereomicroscopy showed that 5% STS significantly reduced brown precipitate intensity and area as compared with no intermediate irrigation (p < .05, Chi-square, generalized linear model, and Tukey's multiple comparison tests). Utilizing ToF-SIMS, 5% sodium thiosulfate was most effective in reducing the components representing para-chloroaniline and chlorhexidine gluconate. CONCLUSION: The 5% sodium thiosulfate was most effective among other intermediate treatments, assessed by stereomicroscopy and ToF-SIMS.

Evaluating dental students' perspectives on the concurrent teaching of didactic and case-based courses.

PURPOSE: To evaluate student perception of integrating biomedical and clinical sciences based on survey of dental students on the concurrent teaching of a didactic systems-based course and a case-based course. METHODS: First-year to fourth-year students (DS1-DS4) students were surveyed for their experiences in concurrent teaching. Student response rate for the survey was 55% (229/420). Pearson's Chi-squared tests and Kruskal-Wallis rank sum tests were used to assess statistical significance (p < 0.05). RESULTS: Of the students surveyed, 83% strongly agreed or agreed that concurrent teaching of the didactic and case-based courses helped them better understand the biomedical science background and the clinical ramifications (p < 0.001). On average, 75% percent strongly agreed or agreed that concurrent teaching kept them engaged, motivated, think critically, apply the course content and prepare for clinical practice (p < 0.001). Of the students surveyed, 69% support expanding concurrent teaching to all four years (p < 0.001). Mean responses from DS1 and DS4 students differed for questions relating to understanding of biomedical sciences, critical thinking and application to clinic (p < 0.01). Qualitative data showed that students enjoyed the reinforcement of concepts and application to clinical scenarios. CONCLUSIONS: Concurrent teaching of didactic and case-based learning courses, thus showing clinical relevance of biomedical sciences in the first year of dental curriculum, is perceived by students as an effective method of educating dental students. Such integrative learning process with horizontal and vertical integration and concurrent curriculum is even more relevant with the implementation of the integrated national board dental examination.

Assessment of the cytotoxic effects and chemical composition of the insoluble precipitate formed from sodium hypochlorite and chlorhexidine gluconate.

AIM: To investigate (1) the cytotoxic potential of the brown precipitate (BP) formed with sodium hypochlorite (NaOCl) and chlorhexidine gluconate (CHX), using both a small animal model of Caenorhabditis elegans (C. elegans) and cultured human gingival fibroblasts; and (2) the chemical composition of BP using Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS). METHODOLOGY: Brown precipitate was obtained by mixing equal volumes of 6% NaOCl and 2% CHX and separating the BP from clear supernatant by centrifugation. The brown precipitate was weighed and solubilized in dimethyl sulfoxide for cytotoxicity experiments. The cytotoxic effect of BP was assessed using C. elegans larvae and primary immortalized human gingival fibroblasts-hTERT (hTERT-hNOF) cells. Various dilutions of BP (25 ng/µL-150 ng/µL), supernatant (0.15% v/v), NaOCl (1:100-1:1000 dilutions of 6% NaOCl) or CHX (1:500-1:1000 dilutions of 2% CHX) along with vehicle control (0.5% v/v ethanol and 0.15% v/v DMSO) or untreated control (growth medium) were tested on C. elegans larvae and hTERT-hNOF cells. Viability was assessed in C. elegans larvae using stereomicroscopy and in hTERT-hNOF cells using dehydrogenase-based colorimetric assay. ToF-SIMS was used to assess the chemical composition of BP in comparison with CHX and para-chloroaniline (PCA). The C. elegans and cell line data were analysed using Log-Rank test and Student's t-test, respectively (p < .05). RESULTS: BP-75 ng/µL and BP-150 ng/µL were significantly more toxic to C. elegans larvae than the untreated, vehicle, supernatant or CHX treatment groups (p < .0001). Similarly, in hTERT-hNOF cells, BP-50 ng/µL, BP-75 ng/µL and BP-150 ng/µL induced significant cytotoxicity within 2 h compared with untreated, vehicle, supernatant and CHX treatments (p < .05). ToF-SIMS analysis of BP revealed ion composition characteristic of both CHX and the carcinogen PCA. CONCLUSIONS: Brown precipitate was toxic in both C. elegans larvae and hTERT-hNOF cells. The ToF-SIMS analysis of BP revealed ions characteristic of CHX and PCA that could account for the toxicities observed in C. elegans larvae and human gingival fibroblasts. Because of the insoluble and toxic nature of BP, consecutive use of CHX and NaOCl irrigants should be avoided in root canal treatment.

When should sleep bruxism be considered in the diagnosis of temporomandibular disorders?

OBJECTIVE: Both temporomandibular disorders (TMDs) and sleep bruxism (SB) are known to be destructive to the masticatory system. However, the association between the 2 conditions is poorly understood. The aim of our study was to assess the relationship between TMD and SB through the signs and symptoms in 2 patient groups: TMD only and TMD with SB. STUDY DESIGN: A retrospective chart review was conducted from November 1, 2015, to April 1, 2018, on patients with completed International Network for Orofacial Pain and Related Disorders Methodology history questionnaires and Diagnostic Criteria for Temporomandibular Disorder clinical examinations. Fifty-two patients, including 12 with TMD only and 40 with TMD with SB, met the study criteria. Subjective descriptions and objective measurements of patient symptoms were investigated. The χ2 test and Fisher's exact test were used for statistical analysis. RESULTS: The TMD with SB group exhibited increased oral behaviors compared with the TMD-only group (P = .0004). The TMD with SB group also experienced more headaches compared with the TMD-only group (P = .045). CONCLUSIONS: Our results revealed that patients with jaw pain who self-report increased oral behaviors and/or exhibit temporal headaches should be evaluated for sleep bruxism.