Composite resins may undergo wear by the action of chemical substances (e.g., saliva, alcohol, bacterial acids) of the oral environment, which may affect the material's structure and surface properties. This study evaluated the effect of acidic substances on the surface properties of a micro-hybrid composite resin (Filtek Z-250). Eighty specimens were prepared, and baseline hardness and surface roughness (KMN0 and Ra0, respectively) were measured. The specimens were subjected to sorption (SO) and solubility (SL) tests according to ISO 4049:2009, but using different storage solutions: deionized water; 75/25 vol% ethanol/water solution; lactic acid; propionic acid; and acetic acid. The acids were used in two concentrations: PA and 0.02 N. pH was measured for all solutions and final hardness (KMN1) and surface roughness (Ra1) were measured. Data were analyzed with paired t-tests and one-way ANOVA and Tukey's test (a=5%). All solutions decreased hardness and increased the Ra values, except for the specimens stored in water and 0.02 N lactic acid, which maintained the hardness. All solutions produced similar SO and SL phenomena, except for the 0.02 N lactic acid, which caused lower solubility than the other solutions. Ethanol showed the highest pH (6.6) and the 0.02 N lactic acid the lowest one (2.5). The solutions affected negatively the surface properties of the composite resin; in addition, an acidic pH did not seem to be a significant factor that intensifies the surface degradation phenomena.

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While Triticum sp. has been shown to act in wound healing, stimulating collagen synthesis by fibroblasts, the use of this plant extract has yet to be assessed in vivo, in commercially viable presentations. This study used rabbits and assessed, on days seven, 14, and 21, the presence or absence of granulation tissue and epithelialization, histopathological structures, and scar quality through the breaking and tension strength. Treatments, performed for 21 days, were aqueous extract of T. aestivum at a concentration of 2mg/mL (group I) and 10mg/mL (group II) and a nonionic cream (control group). We demonstrate that the formation of granulation tissue was not significantly different between treatments. In the analysis of epithelial tissue, wounds in group II differed from other treatments by day 7. On days 14 and 21 there was no significant clinical difference between groups. In the histopathological evaluation, scar quality and rupture strength did not differ between the groups in the studied period. In the tension strength evaluation, group I differed from the others, presenting a higher tension strength overall. The studied treatments did not differ regarding healing evolution of the skin wounds, but T. aestivum extract, at 2mg/mL, presents better results in the tension strength evaluation.

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