Objective. The aim of the study was to characterize and evaluate the stability, antimicrobial activity, cytotoxicity, and remineralizing effects of silver nanoparticles and fluoride anticaries agent (AgF) on staining dental enamel. Materials and Methods. An experimental AgF solution was prepared and compared to silver diamine fluoride (SDF). First, the AgF was characterized and the stability was evaluated by transmission electron microscopy (TEM). Streptococcus mutans, Enterococcus faecalis, and Escherichia coli strains were used to evaluate the minimum inhibitory and bactericidal concentration and cytotoxicity performed using L929 fibroblastic cells by MTT test. Caries‐like lesions induced by pH‐cycling in human enamel were obtained, and then, the superficial microhardness, cross‐sectional microhardness (CSMH), scanning electron microscopy (SEM), and energy‐dispersive X‐ray spectroscopy (EDS) were performed. Photographic images were taken to analyze the enamel staining. Results. The AgF showed stableness in long term with bacteriostatic and bactericidal actions without cytotoxicity. Enamel remineralization, in surface and in depth (CSMH), was observed when the AgF was used, and it was similar to SDF. SEM showed enamel precipitation, and EDS observed the presence of P, Ca, Au, Ag, and Cl elements. Contrary to SDF, AgF did not stain the enamel. Conclusion. The nano silver fluoride anticaries agent tested presented long‐term stability, superficial and in‐depth remineralizing capacity with antimicrobial potential and biocompatibility and did not stain the enamel.

The acellular dermal matrix (ADM) was introduced in periodontology as a substitute for the autogenous grafts, which became restricted because of the limited source of donor's tissue. The aim of this study was to investigate, in vitro, the distribution, proliferation and viability of human gingival fibroblasts seeded onto ADM. ADM was seeded with human gingival fibroblasts for up to 21 days. The following parameters were evaluated: cell distribution, proliferation and viability. Results revealed that, at day 7, fibroblasts were adherent and spread on ADM surface, and were unevenly distributed, forming a discontinuous single cell layer; at day 14, a confluent fibroblastic monolayer lining ADM surface was noticed. At day 21, the cell monolayer exhibited a reduction in cell density. At 7 days, about to 90% of adherent cells on ADM surface were cycling while at 14 and 21 days this proportion was significantly reduced. A high proportion of viable cell was detected on AMD surface both on 14 and 21 days. The results suggest that fibroblast seeding onto ADM for 14 days can allow good conditions for cell adhesion and spreading on the matrix; however, migration inside the matrix was limited.

The aim of the present study was to evaluate the effect of systemic administration of probiotics (PROB) on the progression of experimentally induced oral and intestinal mucositis in rats immunosuppressed by chemotherapy (5-fluorouracil: 5-FU). Twenty-four rats were divided into the following groups (n=6): GC (control), GPROB, G5FU and G5-FU/PROB. Groups GPROB and G5-FU/PROB received 1 g of probiotic incorporated into each 100 g of feed (Bacillus subtilis, Bifidobacterium bifidum, Enterococcus faecium and Lactobacilllus acidophilus), beginning 30 days before oral mucositis induction. Groups G5FU and G5-FU/PROB received 60 mg/kg of 5-FU on days 0 and 2. The left oral mucosa of each animal was irritated by mechanical trauma (days 1 and 2). On days 3 and 7, three animals from each group were sacrificed, and their oral mucosa and small intestine were biopsied and processed for histopathological analysis. Groups G5-FU and G5-FU/PROB showed ulcerated oral lesions at day 3, with progression in group G5-FU and regression in group G5-FU/PROB at day 7. Histologically, less severe signs of inflammation in the oral mucosa were observed in group G5-FU/PROB than in group G5-FU. Regarding the intestine, villus-related defects of lesser magnitude were observed in group G5-FU/PROB, compared with group G5-FU. Group GPROB showed greater villus height than group GC. It can be concluded that probiotic supplementation reduced oral and intestinal inflammation in immunosuppressed rats with experimentally induced mucositis, and may protect the intestine from changes induced by chemotherapy, thus contributing to overall health.