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Dental adhesives hydrolyze in the mouth. this study investigated the water sorption (SoR), solubility (SoL) and cytotoxicity (cYto) of experimental adhesives containing nitrogen-doped titanium dioxide nanoparticles (n_tio 2). Specimens (n = 15/group [SOR, SOL]; n = 10/group [CYTO]) of unaltered Clearfil SE Protect (CSP), OptiBond Solo Plus (OSP), Adper Scotchbond (ASB) and experimental adhesives (OSP + 25% or 30% of N_TiO 2) were fabricated, desiccated (37 °C) and tested for SOR and SOL according to ISO Specification 4049 (2009). CYTO specimens were UV-sterilized (8 J/cm 2) and monomer extracted in growth medium (1, 3 or 7 days). Human pulp cells were isolated and seeded (0.5 × 10 4) for MTT assay. SOR and SOL data was analyzed using GLM and SNK (α = 0.05) and CYTO data was analyzed with Kruskal-Wallis and SNK tests (α = 0.05). SOR and SOL values ranged from 25.80 μg/mm 3 (30% N_TiO 2) to 28.01 μg/mm 3 (OSP) and 23.88 μg/mm 3 (30% N_TiO 2) to 25.39 μg/mm 3 (25% N_TiO 2). cYto results indicated that pulp cells exposed to experimental materials displayed comparable viabilities (p > 0.05) to those of OSP. Experimental materials displayed comparable SOR, SOL and CYTO values (p > 0.05) when compared to unaltered materials. N_TiO 2 incorporation have not adversely impacted SoR, SoL and cYto properties of unaltered adhesives. Resin composite restorations are currently the most prevalent medical intervention in human beings with more than five hundred million restorations placed globally every year 1. Such popularity amongst patients and clinicians precipitates from their mercury-free compositions 2 , outstanding esthetic properties, and their minimally invasive and ultra-conservative restorative techniques 3. Their clinical use involves the removal of demineralized and bacteria-contaminated tooth structure, application of phosphoric acid (37%, 15-30 s), and the subsequent application of a primer and a dental adhesive resin in preparation for the intraoral fabrication of the resin composite restoration 4. The formation of the hybrid layer starts with the penetration of uncured monomers into water-rich, mineraldepleted areas of dentin, followed by the envelopment of exposed collagen fibrils, and the subsequent in situ polymerization by on-demand visible light irradiation 5. Its successful completion 6 should allow for the establishment of a crosslinked 7 and hermetically sealed 3-dimensional polymer-collagen network 6 capable of reducing microleakage, bacterial invasion, marginal staining, secondary caries and pulpal irritation 8. However, because these materials contain both hydrophilic and hydrophobic moieties in a single product 9 , they tend to become chemically unstable when placed in contact with moist dentin 10. The physical manifestation of such instability is translated into materials that phase-separate 11 and display inadequate degrees of conversion 12 .

Background and objective:Previous studies have demonstrated an association between the IL10 promoter rs6667202 (C > A) single-nucleotide polymorphism (SNP) and grade C, stage 3 or 4 periodontitis (Perio4C) in the Brazilian population, where the altered A allele was detected more frequently in these patients. However, no functional analysis of this variation has yet been performed. Thus, the objective of this preliminary study was to evaluate the functionality of rs6667202 in gingival fibroblasts (GFs) of individuals with Perio4C and with periodontal health (PH) stimulated with Aggregatibacter actinomycetencomitans protein extract (AaPE).Methods: Patients with PH and Perio4C were segregated according to their genotype (AA, AC, or CC), and a biopsy was performed to establish the culture of the GFs.After GFs exposure to AaPE at 5 µg/ml for 1.5 h, RNA was extracted to analyze IL10 expression by qPCR. Aliquots of the cell's supernatant were subjected to immunoenzymatic analysis (MAGpix) to detect interleukin-10 (IL-10). Results:In PH, the genotypes AA and AC are related to less expression of IL10 (p = 0.027 and p < 0.0001) and less production of IL-10 (p = 0.002 and p = 0.001), when compared to CC. In Perio4C, there was no statistical difference between the genotypes (p > 0.05), although a lower IL-10 expression and release compared with PH CC was seen (p = 0.033 and p < 0.001). Conclusion:The rs6667202 SNP is functional in PH, as it decreases the expression and production of IL-10. In Perio4C, other factors may be masking its action by altering the IL-10's response.

Background Grade C, Stage 3–4 Periodontitis (Perio4C) is a rapidly destructive disease caused by an unequilibrated immune response that starts after the primary contact of the periodontopathogens with the gingival tissue. However, it is still unclear how this imbalanced response initiates and what is the role of the connective tissue cells in the progression of this disease. Thus, this study aims to assess the local immune response of Perio4C patients through the exposure of primary gingival fibroblast cells (GFs) with Aggregatibacter actinomycetemcomitans protein extract (AaPE) and the quantification of the inflammatory cytokines interleukin (IL)‐4, IL‐17, tumor necrosis factor (TNF)‐α, IL‐1β, interferon (IFN)‐γ, and IL‐10 super‐family members (IL‐10, IL‐19, and IL‐24) secreted by them. Methods Gingival biopsies from nine periodontally health (PH) and eight Perio4C patients were harvested, and the primary culture of GFs was obtained. The cells were exposed to AaPE (5 and 20 μg/ml) and 12‐myristate 13‐phorbol acetate and ionomycin – calcium salt (PMA). The supernatant was collected after 1.5 and 3 h, and a cytokine panel was evaluated. Results Clustering analysis indicated dissimilar and stimuli‐dependent cytokine production between Perio4C and PH subjects. Perio4C GFs presented lower production of IL‐4, TNF‐α, IFN‐γ, IL‐17, IL‐10, IL‐24, and IL‐19, while IL‐1β levels were similar to the PH group, leading to a disruption in the pro‐/anti‐inflammatory cytokine ratio (p < 0.05). IL‐1β and IL‐10 super‐family were the most discriminative representants for PH and Perio4C, respectively. Conclusion GFs from individuals with Perio4C tended to hypo‐respond to stimulation with AaPE, producing lower concentrations of some pro‐ and anti‐inflammatory molecules, trending to develop a pro‐inflammatory extracellular environment.