“…In both flat and highly rough surfaces, the absorption does not depend on the ion, molecular, or particle size of the adsorbate. However, for rough surfaces such as carious teeth (Gonzalez-Gonzalez, 1997), it is expected that D values between 2 and 3 reveal the absorbate/adsorbate size-dependent behavior of kinetics and thermodynamics due to changes in absorbent accessible surface area (Adamson & Gast, 1997). Therefore, the gas-phase concentration of the metal compounds is not the only parameter that has an effect on their sorption by caries-like teeth, and further studies are need to gain a better understanding of this phenomenon.…”