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This work aimed to investigate interactions between antibody-opsonized SARS-CoV-2 and monocytes enriched from human peripheral blood mononuclear cells (PBMC) to determine whether antibody dependent enhancement might contribute to the pathophysiology of COVID-19. Pre-incubation of SARS-CoV-2 with sera from hospitalized COVID-19 patients led to significantly increased virus uptake and viral replication in monocytes. Remarkably, SARS-CoV-2 pre-incubated with sera from patients with severe COVID-19 but not those with mild disease or post vaccination strongly increased IL-6 secretion by monocytes. Antibody dependent viral uptake was partially inhibited by monoclonal anti-FcγRIIa antibody whereas IL-6 secretion was completely abolished. FcγRIIa preferentially binds IgG2, and sera from patients with severe COVID-19 contained lower IgG2 levels as compared to mild COVID-19 cases whereas IgG1 levels were increased. These data suggests that FcγRIIa-mediated binding of antibody-opsonized SARS-CoV-2 critically impacts monocytic inflammatory cytokine release and COVID-19 pathophysiology. [ABSTRACT FROM AUTHOR]

This study investigates the surface quality and bacterial adhesion properties of various dental materials, including indirect composites, veneering composites, direct composites, polyether ether ketone (PEEK), and two millable polymethyl methacrylate (PMMA). Material specimens were processed following manufacturer instructions, initially evaluated for surface roughness and Streptococcus sanguinis (S. sanguinis) adhesion. Subsequently, toothbrushing simulation was employed to simulate aging, and changes in material surfaces were assessed via roughness measurements and bacterial adhesion testing. Prior to simulated aging, direct and indirect composites exhibited the lowest roughness values. However, after the simulated toothbrushing, veneering composites displayed the highest roughness levels. Both PMMA materials demonstrated the highest S. sanguinis adhesion levels, both before and after artificial aging. Interestingly, the indirect composite material showed a reduction in bacterial adhesion following toothbrushing simulation. Surprisingly, this study did not reveal a clear correlation between roughness and bacterial adhesion. [ABSTRACT FROM AUTHOR]

The high demands on the clinical performance of a single-tooth provisional restoration necessitate that said performance be examined. The authors evaluated 24 teeth evaluated. Two test groups received bis-acrylic composite for provisional crowns (n = 12) and a single-unit, self-supporting, malleable, light-curing composite crown (n = 12). Final crowns (n = 24) served as paired controls. Evaluation of clinical success was measured using previously selected subcategories of FDI criteria. Statistical analysis was performed using McNemar's Test (α = 0.05). The null hypothesis of no improvement of the definitive crown relative to the provisionals was rejected at the 5% significance level (McNemar's P value <.001, Bonferroni corrected). Of the provisional crowns, 75% received a clinically insufficient valuation, while only 8% of the definitive crowns did. The authors concluded that, independent of the manufacturing process, a bis-acrylic composite provisional crown cannot serve as a replacement for a conventionally manufactured definitive crown. [ABSTRACT FROM AUTHOR]