Desenvolvimento de compósito fotoativado para aplicação em coberturas periodontais temporárias

Abstract

The application of a material after periodontal surgery is recommended to reduce postoperative bleeding, to protect the wound area and to avoid the formation of excessive granulation tissue. The current trend is the development of new biomaterials eugenol-free for surgical application. The aim of this study was to develop and characterize a periodontal dressing based on photopolymerizable methacrylate monomers. For this purpose, a screening was made to determine the best formulation based on the ease of handling and the use of Exothane 8 , camphorquinone, silica and quartz particles. Three groups were tested: Gperio (Group of periodontal dressing Periobond®, Dentsply); Gbar (Group of periodontal dressing Barricaid®, Caulk), which served as the reference group and Gexp (Group of experimental material). The physical-mechanical performance of the experimental composite and the commercial references Periobond® and Barricaid® (control group) were tested using in vitro tests of tensile strength (n = 15) and sorption and solubility (n = 10). Cytotoxicity (MTT colorimetric assay) and genotoxicity by micronuclei (MN) tests were performed in a cell lineage of mouse fibroblasts 3T3/NIH, in triplicate, in order to characterize the biological response of these materials. Microbiological test assess the amount of viable bacteria of Enterococcus faecalis anaerobic and aerobic and total microorganisms. Data were subjected to statistical analysis based on the model of normal distribution and equal variance One-Way ANOVA, considering the value of P<0.05 as statistically significant. There were no statistically significant differences between the median values of Gexp and Gbar, for ultimate tensile strength. Regarding the sorption there was statistical difference between Gperio and Gexp and between Gperio and Gbar (P=<0.001). There was no difference when comparing Gbar and Gexp. The solubility showed no statistical difference between groups. In general, the cytotoxic effects of the materials were time dependent according to eluate extraction periods (24h, 48h and 7 days). No statistical difference at 24h between Gexp and Gperio. At 72h, differences were observed between Gexp and Gperio (P<0.001) with Gexp showing the best results. Similar results were seen between Gbar and Gperio (P<0.001). At 7 days, statistical difference was observed between Gbar and Gperio (P<0.05). In genotoxicity test no difference was found among the groups. In microbiological assay no statistical difference was found for E. faecalis anaerobic, E. faecalis aerobic and for total microorganisms. We conclude that Gexp experienced similar behavior to the commercial samples and can be possibly used as a periodontal dressing; however, more studies are needed at pre-clinical and clinical levels