RESUMO
OBJECTIVE: To evaluate the effect of charcoal-based dentifrices on the color change (CC) and surface wear (SW) of resin composites. MATERIALS AND METHODS: Five dentifrices, including three toothpastes: Colgate total-12 (C12), Black is the new White (CPX), and Natural (NAT); and two powders: Carvvo (CVV) and Whitemax (WMX), were evaluated. Composite blocks (5x5x2mm- Z350 3 M/ESPE, shade A2) were subjected to 417 and 5004 brushing cycles. The CC (n = 7, CIEDE2000; ΔE00 ) was evaluated using a spectrophotometer. SW (n = 5) was assessed using profilometry. The dentifrice particles were characterized by scanning electron microscopy (SEM). RESULTS: In 417 brushing cycles, resin composite exhibited higher color change upon being exposed to NAT, CVV and WMC than to C12 (p ≤ 0.05). In 5004 brushing cycles, resin composite showed higher color change values when exposed to all dentifrices, except C12 (p ≤ 0.05). The powders promoted higher SW on resin composite than C12 in both evaluation times (p ≤ 0.05). In 417 cycles, WMX caused higher SW on composite than C12, CPX, and NAT (p ≤ 0.05). No significant different SW was found between powders and charcoal-based toothpastes after 5004 brushing cycles (p > 0.05). SEM showed larger particles for powder than for toothpaste dentifrices. CONCLUSION: Within the limitations of this study, both null hypotheses have been rejected. Resin composites exposed to charcoal-based dentifrices exhibited significantly (p ≤ 0.05) higher color change and surface wear than conventional toothpastes. CLINICAL SIGNIFICANCE: Color change and surface wear shown by charcoal dentifrices may compromise the longevity of restorations.
