The pellicle and erosion.

All tooth surfaces exposed to the oral environment are naturally coated by the acquired salivary pellicle. The pellicle is composed of adsorbed macromolecular components from saliva, gingival crevicular fluid, blood, bacteria, mucosa and diet. The pellicle (formed in situ/in vivo) functions as a semipermeable network of adsorbed salivary macromolecules and provides partial protection against acidic challenges; however, it cannot completely prevent demineralization of the tooth surface. The physiological pellicle reduces calcium and phosphate release from the enamel, and much less from the dentinal surface. With high probability, calcium- and phosphate-binding peptides and proteins adsorbed in the basal pellicle layer are of main relevance for the erosion-reducing effects of the natural salivary pellicle. Improvement of the pellicle's protective properties by dietary components (e.g. polyphenolic agents) might be a promising erosion-preventive approach that, however, needs validation by in situ experiments.