Otro
Effects of light-curing time on the cytotoxicity of a restorative composite resin on odontoblast-like cells
Registro en:
Journal of Applied Oral Science. Bauru-sp: Univ São Paulo Fac Odontologia Bauru, v. 18, n. 5, p. 461-466, 2010.
1678-7757
S1678-77572010000500006
WOS:000284590700006
S1678-77572010000500006-en.pdf
Autor
Fabio Aranha, Andreza Maria
Aparecida Giro, Elisa Maria
Hebling, Josimeri
Rosetti Lessa, Fernanda Campos
de Souza Costa, Carlos Alberto
Resumen
This in vitro study evaluated the cytotoxicity of an experimental restorative composite resin subjected to different light-curing regimens. Methods: Forty round-shaped specimens were prepared and randomly assigned to four experimental groups (n=10), as follows: in Group 1, no light-curing; in Groups 2, 3 and 4, the composite resin specimens were light-cured for 20, 40 or 60 s, respectively. In Group 5, filter paper discs soaked in 5 mu L PBS were used as negative controls. The resin specimens and paper discs were placed in wells of 24-well plates in which the odontoblast-like cells MDPC-23 (30,000 cells/cm(2)) were plated and incubated in a humidified incubator with 5% CO(2) and 95% air at 37 degrees C for 72 h. The cytotoxicity was evaluated by the cell metabolism (MTT assay) and cell morphology (SEM). The data were analyzed statistically by Kruskal-Wallis and Mann-Whitney tests (p<0.05). Results: In G1, cell metabolism decreased by 86.2%, indicating a severe cytotoxicity of the non-light-cured composite resin. on the other hand, cell metabolism decreased by only 13.3% and 13.5% in G2 and G3, respectively. No cytotoxic effects were observed in G4 and G5. In G1, only a few round-shaped cells with short processes on their cytoplasmic membrane were observed. In the other experimental groups as well as in control group, a number of spindle-shaped cells with long cytoplasmic processes were found. Conclusion: Regardless of the photoactivation time used in the present investigation, the experimental composite resin presented mild to no toxic effects to the odontoblast-like MDPC-23 cells. However, intense cytotoxic effects occurred when no light-curing was performed. Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)