Short-term "in vivo" study on cellular DNA damage induced by acrylic Andresen activator in oral mucosa cells

Objectives: To analyse through comet assay and micronucleus test the viability and DNA damage occurred in buccal mucosa epithelial cells after a short-term exposure to Andresen activator resin monomers. Setting and Sample Population: Test group consisting of 26 subjects was treated with Andresen activator; 16 subjects who had never undergone orthodontic treatment were enrolled in the control group. Material & Methods: Buccal mucosa samples were collected before treatment and after 7, 15, 30, 60 and 90 days. The analyses performed on the cells included the following: cellular viability, comet assay and micronucleus test. Mean ± SD were calculated for cellular viability, tail moment, tail intensity, tail length, micronuclei, binuclear and bud cells. Significance (P < 0.05) was evaluated with Dunnett's test. Results: Cellular viability did not change during observational time, and its trend was similar to the controls. Tail moment and tail intensity significantly increased after 30 and 60 days, respectively, whereas tail length remained unchanged over time in the test group; the same parameters did not change in the control group. In the test group, micronuclei, binuclear and bud cells significantly increased after 30, 60 and 90 days, respectively. Conclusion: The resin monomers of the Andresen activator cause genotoxic effects detectable through comet assay and micronucleus test, but they do not produce clear cytotoxic effects after a 90 days exposure.