Efeito transdentinário de agentes químico-mecânicos na citotoxicidade e produção de radicais livres por células pulpares

Abstract

The aim of the study was to evaluate the cytotoxic effect and production of free radicals by human pulp cells of two enzymatic agents for chemical-mechanical removal of carious tissue. Cells were seeded in 24-well plates (50,000 cells/well) and after 24 hours, a metal device/dentin disc (3mm thick)/silicone ring assembly was inserted into each well. The materials were applied according to the groups: control without material; 35% hydrogen peroxide for 2 minutes; PapacárieDuo (PD) for 30 seconds; PD for 2 minutes; Brix3000 (BX) for 30 seconds and BX for 2 minutes (n=8). Viability tests (MTT), production of nitric oxide (ON, Griess reagent) and production of reactive oxygen species (ROS, probe DCFH-DA) were performed 24 hours after application of the materials. Data were submitted to one-way ANOVA statistical tests complemented by Tukey (p<0.05). For cell viability, the BX groups at both times did not differ from the control (p>0.05), while the PD group 30 seconds and 2 minutes showed a decrease in viability of 21.1% and 58.4% respectively (p<0 .05). As for the quantification of NO, there was no statistical difference between the different groups (p>0.05). For the quantification of ROS, the 30-second and 2-minute PD groups showed an increase of 171.2% and 75.1% respectively when compared to the control (p<0.05). It was concluded that the transdentinal action of the PD material presented cytotoxic potential and increased production of ROS by pulp cells, at application times of 30 seconds and 2 minutes.