ATOMIC-FORCE MICROSCOPY STUDIES OF THE EFFECTS OF CHEMICALS ON THE DENTIN TISSUE

Atomic force microscopy (AFM) was used to monitor the effect of several chemicals on the dentin tissue. The action of three different etching agents, namely aqueous solutions of phosphoric acid, polyacrylic acid and EDTA (at clinically relevant concentrations) on dentin was followed in real time. The etched dentin was then treated with an aqueous solutions of glutaraldehyde and hydroxyethylmethacrylate (part of a commercial bonding agent), and the effect of the latter on the dentin morphology was studied as a function of the etching agent used. Results show different mode of actions of the chemicals tested, and that hydroxyethylmethacrylate undergoes a polymerization reaction on EDTA-treated dentin. More generally, it is shown that the use of AFM for real-time imaging of wet samples under normal pressure conditions can give important information on the effects of chemicals on the dentin tissue.