Auger electron spectroscopy of iron in dental pellicle from stainers and non-stainers.

Stainers and non-stainers were selected on the basis of their individual tendency to develop extrinsic tooth discolorations from a chlorhexidine mouth rinse. Pellicle was allowed to form in vivo on dental enamel slabs in both stainers and non-stainers. The slabs were then exposed to chlorhexidine 0.2% and a neutral iron salt solution extraorally either once or until a brownish discoloration appeared from the stainers. The pellicle was examined for its content and distribution of iron by Auger electron spectroscopy (AES). Pellicle from stainers showed higher concentrations of iron than pellicle from non-stainers.