EVALUATION of Cytotoxic effects of GUEDES-PINTO'S PASTE AND CALCIUM HYDROXIDE

Objectives: The aim of this work was to evaluate the cytotoxicity in vivo and in vitro of Guedes-Pinto paste and calcium hydroxide, materials utilized in endodontic therapy deciduos teeth . Methods:We used the NIH 3T3 cell line (ATCC CRL 1658) for available cell viability and pulp fibroblasts (FP1), in studies in vitro. The materials were directly applied to coverslips that were placed in contact with the cultured cells. The control group was cultures that received plain coverslips. In long-term assay (cell survival), the experimental periods were 1, 3, 5, and 7 days, and in short-term assay (cell viability), the periods were 0, 4, 8, and 12 hrs. We determined cell number and cell viability (%) by counting the cells in a hemocytometer, using the Trypan blue dye exclusion assay and MTT. In studies in vivo, the materials were evaluate in the subcutaneous reactions of mice. Results: The analysis of the reaction of the exposed subcutaneous fabric from mice with Guedes-Pinto paste and calcium hydroxide paste with physiologic serum demonstrated that, in the Guedes-Pinto paste mice, less intense inflammatory reaction was observed. In the experiments in vitro, the data analyses obtained in our experiments allowed us to observe that groups treated with Guedes-Pinto paste had viable cells numbers and percentages lower than those of the control group, but allowed for more long-term cellular growth. Conclusion: Our study established the reduced cytotoxicity of Guedes-Pinto paste, in fibroblast culture tests, compared with calcium hydroxide paste with physiologic serum