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Increased overall exposure of the Brazilian population to fluoridated water and fluoridated dentifrices has been identified as the main factor in the reduction of caries prevalence. Thus, the objective of the present study was to evaluate the distribution of caries in a group of 437 children ranging from 6 to 12 years of age, residing in a city without a water supply fluoridation system and without a preventive dentistry program, with the aim of orienting future health measures towards improved cost-effectiveness. Clinical examination was performed on all the children, focusing on the indices defs (decayed, extracted, and filled primary dentition surfaces) and DMFS (decayed, missing, and filled permanent dentition surfaces), representing the number of dental surfaces that were either decayed, missing or with extraction indicated, or restored. Analysis of accumulated disease frequency in relation to the population showed that 37% of the children presented 70% of all the tooth disease, with a mean defs + DMFS of 28.6. This distribution demonstrates the phenomenon of polarization, in which most of the disease and treatment needs are concentrated in a small portion of the population.

Recently, the application of copper oxide nanoparticles (CuO-NPs) has increased considerably, primarily in scientific and industrial fields. However, studies to assess their health risks and environmental impacts are scarce. Therefore, the present study aims to evaluate the toxicological effects of CuO-NPs on the duckweed species Landoltia punctata, which was used as a test organism. To accomplish this, duckweed was grown under standard procedures according to ISO DIS 20079 and exposed to three different concentrations of CuO-NPs (0.1, 1.0, and 10.0 g L(-1)), with one control group (without CuO-NPs). The toxicological effects were measured based on growth rate inhibition, changes in the plant's morphology, effects on ultrastructure, and alterations in photosynthetic pigments. The morphological and ultrastructural effects were evaluated by electronic, scanning and light microscopic analysis, and CuO-NPs were characterized using transmission electron microscopy (TEM), zeta potential, and superficial area methods of analysis. This analysis was performed to evaluate nanoparticle size and form in solution and sample stability. The results showed that CuO-NPs affected morphology more significantly than growth rate. L. punctata also showed the ability to remove copper ions. However, for this plant to be representative within the trophic chain, the biomagnification of effects must be assessed.

The effects of the heavy metals copper (Cu) and lead (Pb) on Sargassum cymosum were evaluated by determining uptake capacity, growth rates, photosynthetic efficiency, contents of photosynthetic pigments and phenolic compounds, 2,2-diphenyl-1-picrylhydrazyl radical-scavenging capacity, and morphological and cellular changes. S. cymosum was cultivated with Cu and Pb separately and combined at concentrations of 10, 25, and 50 μM for 7 days in laboratory-controlled conditions. Seaweeds under Cu treatment showed the highest biosorption capacity, and growth rates were significantly reduced compared to the control. The photosynthesis/irradiance curves showed alterations in kinetic patterns in the metal-treated samples. Specifically, Cu treatment alone inhibited electron transport rate (ETR) response, while Pb alone induced it. However, samples treated with both Cu and Pb (Cu + Pb) showed inhibition in ETR. The total amount of pigments increased relative to control. Light microscopy showed an increase in phenolic compounds, with physodes migrating towards cortical cells. Scanning electronic microscopy revealed alterations in the typical rough surface of thallus, when compared with control, especially for Pb treatments. Based on these results, it could be concluded that Cu and Pb are stress factors for S. cymosum, promoting alterations in seaweed metabolism and stimulating protective mechanisms against oxidative stress. However, the high bioaccumulation capacity of both heavy metals indicates a possible application for S. cymosum as a biosorbent agent for contaminated wastewater when metals are in low concentrations.

Background:  Animal studies have suggested that home bleaching agents can cause morphological alterations and changes in the proliferative rate of oral epithelium. Methods:  A bleaching agent containing 10% carbamide peroxide with carbopol was used in 11 women (five smokers and six non‐smokers) during a 5‐week period. Two biopsies were performed, one of them 15 days before the beginning of the home bleaching treatment and the other immediately after the 5‐week bleaching treatment. Two analyses were performed in the histological sections obtained from the biopsies: epithelium morphometry and assessment of the epithelium's proliferative activity by proliferating cell nuclear antigen (PCNA) immunohistochemistry. Results:  The home bleaching agent increases epithelium thickness and the PCNA index in both smoker and non‐smoker patients. Conclusion:  Carbamide peroxide (10%) caused an augmentation in the proliferative activity within the basal and parabasal layers of the gingival epithelium, resulting in a change in this tissue's morphometry.

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Because children with type 1 diabetes (DM) are prone to diseases of the buccal cavity, in this transversal study we investigate the prevalence of dental caries, gingivitis and buccal alterations in 26 patients (16F/10M; average age: 10.3 years) from the Diabetic Children's Group at the Federal University Hospital of Santa Catarina, to verify possible correlations among the following variables: index of decayed, missing or filled permanent or deciduous teeth [DMFT or dmft], index of visible plaque [IVP], index of gum bleeding [IGB], dental calculi, gum recession, tongue abnormalities, xerostomia, burning sensation of the mucosa, age at DM diagnosis, administration of insulin; occurrence of DM-related complications; glycemia and glycosilated hemoglobin [GH]. The most frequent alterations were dental calculi (42.3%), xerostomia (38.5%), burning sensation (11.5%), and gum recession (7.7%). The median indices for DMFT/dmft, IVP and IGB were 2.0, 27.21% and 10.91%, respectively. Only age and the level of GH were significantly correlated to IVP (r2 = 0.61), whereas the IVP and hypoglycemia correlated to IGB (r2 = 0.63). We conclude that the older the patient and the higher the GH level, the higher the IVP; whereas the higher the IVP and the less frequent the crisis of mild hypoglycemia, the higher the IGB.