Does the whitening dentifrice containing activated charcoal interfere with the properties of dental enamel? Microhardness, surface roughness and colorimetry analyzes

It was concluded that the use of a whitening toothpaste containing activated charcoal caused deleterious effects on the enamel Ra, but did not affect the microhardness of the substrate, besides promoting a color change inferior to the regular non-bleaching toothpaste or 10% carbamide peroxide.