Cytotoxic effects of different concentrations of a carbamide peroxide bleaching gel on odontoblast-like cells MDPC-23.
This study evaluated the cytotoxic effects of a carbamide peroxide (CP) bleaching gel at different concentrations on odontoblast-like cells. Immortalized cells of the MDPC-23 cell line (30,000 cells/cm(2)) were incubated for 48 h. The bleaching gel was diluted in DMEM culture medium originating extracts with different CP concentrations. The amount (microg/mL) of hydrogen peroxide (H(2)O(2)) released from each extract was measured by the leukocrystal violet/horseradish peroxidase enzyme assay. Five groups (n = 10) were formed according to the CP concentration in the extracts: G1-DMEM (control); G2-0.0001% CP (0.025 microg/mL H(2)O(2)); G3-0.001% CP (0.43 microg/mL H(2)O(2)); G4-0.01% CP (2.21 microg/mL H(2)O(2)); and G5-0.1% CP (29.74 microg/mL H(2)O(2)). MDPC-23 cells were exposed to the bleaching gel extracts for 60 min and cell metabolism was evaluated by the MTT assay. Data were analyzed statistically by one-way ANOVA and Tukey's test (alpha = 0.05). Cell morphology was examined by scanning electron microscopy. The percentages of viable cells were as follows: G1, 100%; G2, 89.41%; G3, 82.4%; G4, 61.5%; and G5, 23.0%. G2 and G3 did not differ significantly (p > 0.05) from G1. The most severe cytotoxic effects were observed in G3 and G4. In conclusion, even at low concentrations, the CP gel extracts presented cytotoxic effects. This cytotoxicity was dose-dependent, and the 0.1% CP concentration caused the most intense cytopathic effects to the MDPC-23 cells.
Department of Restorative Denstistry, Piracicaba School of Dentistry, State University of Campinas-UNICAMP, Piracicaba, São Paulo, Brazil.
Adriano Fonseca
AF
de Lima
Fernanda Campos Rosetti
FC
Lessa
Maria Nadir
MN
Gasparoto Mancini
Josimeri
J
Hebling
Carlos Alberto
CA
de Souza Costa
Giselle Maria
GM
Marchi
D000077463:Carbamide Peroxide; D002460:Cell Line; D003743:Dental Enamel / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004338:Drug Combinations; D005782:Gels; D006801:Humans; D006861:Hydrogen Peroxide / Q000737:chemistry; D008855:Microscopy, Electron, Scanning / Q000379:methods; D009804:Odontoblasts / Q000166:cytology* / Q000187:drug effects; D010545:Peroxides / Q000737:chemistry*; D013778:Tetrazolium Salts / Q000737:chemistry; D013844:Thiazoles / Q000737:chemistry; D013997:Time Factors; D014073:Tooth Bleaching / Q000009:adverse effects* / Q000379:methods; D014075:Tooth Discoloration / Q000517:prevention & control / Q000628:therapy; D014508:Urea / Q000031:analogs & derivatives* / Q000737:chemistry
D004338:Drug Combinations; D005782:Gels; D010545:Peroxides; D013778:Tetrazolium Salts; D013844:Thiazoles; D000077463:Carbamide Peroxide; D014508:Urea; D006861:Hydrogen Peroxide; C022616:thiazolyl blue