EVALUATION OF TOXICITY AND EFFICACY OF ORAL ANTISEPTICS RELATED TO DENTAL CELL RESOURCES

Background The objective of this work was to verify the influence of oral antiseptics on cells from human exfoliated deciduous teeth (SHEDs), to establish antisepsis protocols of lower cytotoxicity. Methods 5 × 104 cells were inserted into 24-well plates under culture conditions for 48 hours, divided as group C (control); group BM (peroxide), 3 wells with 1:1 antiseptic/culture medium solution and 3 wells with 1:10 antiseptic/culture medium solution); CP group (triclosan, 1:1 and 1:10); group PP (chlorhexidine, 1:1 and 1:10). Two microbiological tests were also performed, agar diffusion test (AD) and minimum inhibition concentration (MIC). For the AD test, 9 Petri dishes containing Mueller-Hinton agar were prepared in which strains of E. faecalis were inoculated and divided into 4 parts, in which paper discs embedded in the antiseptics were placed (peroxide, chlorhexidine and triclosan, with 50%, 75% and 100% concentrations). The MIC test was performed with Mueller-Hinton broth, with E. faecalis (to McFarland‘s 0.5 scale). 10 mμ of antiseptics were inoculated in these tubes. After 72 h, the samples were read at a spectrophotometer. Data was submitted to two way ANOVA and Tukey test (p≤0.05). Results At the inverted microscope, group C presented cells that appeared closer and with a spreading aspect, besides viability of 92.3% (flow cytometry). In the BM group, the identification of cellular limits were not clear (1:1 with 69% viability), with round cell morphology, closer and non-adherent cells (1:10 with 95% viability). In the CP group the cells were smaller, separated and with few elongations (1:1 with 46.8% viability) – similar with group C (1:10 with 60.1%). In the PP group, cells were small and separated, with a spreading aspect (1:1 with 95.7% viability, and 1:10 with 100% viability). At the microbiological tests, all solutions presented antiseptic properties, although the CP group presented the lowest antimicrobiological results. Conclusion The group with the least morphological influence on the cells was PP. However, due to mutagenicity effect, chlorhexidine-based antiseptics should be avoided when cells are submitted to culture processing. At 1:10 dilution, peroxide-based antiseptic provided excellent viability (95%), although important morphological changes were seen. Regarding the microbiological tests, even at different concentrations and results, all antiseptics in this study were considered effective in eliminating E. faecalis.