In vitro comparison of the color degradation of two computer-aided design/computer-aided manufacturing provisional materials: A 12-month simulation.

Aim: This study evaluated the color aging of two computer aided design/computer aided manufacturing (CAD/CAM) provisional materials of different compositions (polymethyl methacrylate and composite resin) after exposure to thermal aging and immersion in coffee for 3, 6, and 12 intraoral months. Setting and Design: The current in vitro study was conducted from September to December 2021 at the Craniofacial laboratory at the Saint Joseph University in Beirut, Lebanon. Materials and Methods: The shades of 2.0 mm thick, 10.0 mm in diameter disk shaped specimens of VITA CAD Temp® and Ceramill® TEMP were measured using the VITA Linearguide 3D MASTER® and a conversion table to extract the CIE LFNx01aFNx01bFNx01 values on a white background (n = 30). Statistical Analysis Used: The color differences ΔE at 3, 6, and 12 months were calculated and analyzed by repeated measures ANOVA followed by Bonferroni multiple comparisons, univariate analyses, and one sample t tests. Results: The mean ΔET1/T0, ΔET2/T0, and ΔET3/T0 values were significantly higher than the cutoff values for acceptability and perceptibility for the VITA CAD Temp® and the Ceramill® TEMP groups. In addition, the increase in ΔE overtime was significantly greater in the Ceramill® TEMP group compared to the VITA CAD Temp® group. Conclusions: The Ceramill® TEMP changed color more and faster than the VITA CAD Temp®. In addition, whether at 3, 6, or 12 months, the color variations of both materials are not only perceptible but also unacceptable compared to the initial shade.

The Prevalence and Predicting Factors of Temporomandibular Disorders in COVID-19 Infection: A Cross-Sectional Study.

Introduction During the pandemic of coronavirus disease 2019 (COVID-19), an increase in temporomandibular disorders (TMDs) was noticed in infected patients. In the present study, we aimed to assess the prevalence of TMDs during COVID-19 infection and to evaluate associated factors. Methods An observational cross-sectional online survey was conducted in April and May 2021 in order to estimate the prevalence of TMDs in participants who were previously infected with COVID-19. A multivariable logistic regression model was carried out to explore predicting factors of TMDs during COVID-19 infection. Results In total, the prevalence of TMDs during the COVID-19 infection period among participants was 41.9%. High fever episodes (adjusted odds ratio {aOR}: 3.25), gastro-esophageal reflux (aOR: 2.56), and toothache (aOR: 3.83) during COVID-19 illness were found to be positive predictors of TMDs, while vitamin D deficiency was found to be a negative predictor (aOR: 0.28). Conclusion Our study has highlighted a relatively high prevalence of TMDs in COVID-19-infected patients that may conclude TMDs as a possible COVID-19 symptom. Further studies are warranted to confirm the association between TMDs and COVID-19 infection and thereupon include TMDs among the known symptoms of COVID-19.