Randomized in situ evaluation of surface polishing protocols on the caries-protective effect of resin Infiltrant.

The aim of this placebo-controlled randomized in situ study was to evaluate the effect of different surface polishing protocols on enamel roughness, bacterial adhesion and caries-protective effect of a resin infiltrant. Seventy-five bovine enamel samples having artificial caries lesions were treated with a resinous infiltrant and afterwards randomly dividided into five polishing protocols: aluminum oxide flexible disks (Al2O3-Disks), silicon carbide tips (SIC-Tips), silicon carbide brush (SIC-Brush), silicon carbide polyester strips (SIC-Strips) or no polishing [negative control (NC)]. Average surface roughness (Ra) was assessed by profilometry. Samples were mounted in palatal appliances under a mesh for biofilm accumulation. Fifteen volunteers wore the intraoral appliances (14-days) and cariogenic challenge was triggered by sucrose solutions. Biofilm formed was collected for microbiological analysis of caries-related bacteria (Streptococcus mutans, Lactobacillus acidophilus) and demineralization was assessed by cross-sectional microhardness. Mean Knoop hardness numbers (Kg/mm2) were plotted over lesion depth (µm) and area under the lesion curve was subtracted from sound enamel to determine demineralization (ΔS, Kg/mm2xµm). Data were analyzed by ANOVA and post-hoc comparisons (α = 0.05). NC resulted in significantly higher Ra means than Al2O3-Disks and SIC-Strips. Bacterial counts were not significantly different between the groups (p > 0.05). Regards ΔS means, however none of the groups were significantly different to NC (6983.3 kg/mm2xµm /CI 4246.1-9720.5, p > 0.05). Conclusions: Polishing protocols (Al2O3-Disks, SIC-Strips) significantly decreseased roughness of infiltrated-enamel, however none of the polishing protocols could signicantly decrease bacterial counts nor resulted in significant less demineralization

Over-the-counter human immunodeficiency virus self-test kits: time to explore their use for men who have sex with men in Brazil.

Increasing access and frequency of human immunodeficiency virus testing are critical to stemming the epidemic. In Brazil's concentrated epidemic, human immunodeficiency virus prevalence in the men who have sex with men/transgender population far exceeds that in the general population, but testing rates fall below what is needed to ensure early detection and treatment. Over-the-counter human immunodeficiency virus self-testing kits, now available in stores in the U.S., have enormous potential to increase testing access and frequency and to facilitate early detection and treatment. With the advent of human immunodeficiency virus self-testing upon us, it is timely to engage the scientific community, government, and civil society in a dialog around how to best utilize this technology in Brazil. We summarize recent research on over-the-counter testing among men who have sex with men, raise potential questions and challenges to using self-tests, suggest implementation strategies, and outline a research agenda moving forward