Effect of charcoal-based dentifrices on the surface integrity and gloss of lithium disilicate glass-ceramics

Objectives To evaluate the effects of commercially available charcoal-based dentifrices on the surface roughness and gloss retention of glazed lithium disilicate glass-ceramics subjected to simulated toothbrushing. Materials and Methods Seventy-two glazed lithium disilicate specimens (IPS e.max CAD, Ivoclar) were randomly assigned to three groups (n = 24): Carvvo (CV), Curaprox Black is White (CPBW), and Colgate Total 12 (C12 – control). Toothbrushing simulations were performed for 5.000, 10.000, and 20.000 cycles. Surface roughness (Ra) and gloss (GU) were measured at baseline and after each brushing interval. Three-dimensional profilometry and scanning electron microscopy (SEM) were used for qualitative surface characterization. Abrasive particles were analyzed using SEM. Results Charcoal-based dentifrices increased surface roughness and reduced gloss values of glazed ceramics, with CV showing the highest abrasiveness. CPBW demonstrated intermediate effects, while C12 preserved surface integrity and even enhanced gloss. Three-dimensional profilometry and SEM confirmed more pronounced surface wear in groups CV and CPBW. Abrasive particles from charcoal-based dentifrices were irregular, larger, and sharper compared to the spherical and uniform particles in C12. Conclusions Charcoal-based dentifrices significantly compromise the surface quality of lithium disilicate glass-ceramics by increasing roughness and reducing gloss, which may affect esthetics and long-term performance. Conventional dentifrice had no deleterious effect on ceramic surfaces. Clinical Relevance The routine use of charcoal-containing toothpastes by patients with ceramic restorations may accelerate surface wear and reduce optical properties, compromising the longevity and esthetic outcomes of restorative treatments.