– IgA, IgG, albumin, lysozyme, α‐amylase and glucosyltransferase were identified in the saliva coat which forms on hydroxyapatite exposed to whole saliva. It is suggested that these proteins may be involved in binding microorganisms to saliva coated hydroxyapatite in model studies.

A mechanism of concentration of fluoride (and phosphate) ions in plaque is suggested; calcium ions from saliva are bound to fixed acidic groups in the plaque, and fluoride (or phosphate) ions are attracted to the bound calcium as counterions. The principle was demonstrated by equihbrium dialysis of calcium-treated acidic ionic exchange material (Sephadex® SP and CM) against 1 part/10^ of fluoride. A part of the fluoride was found to be bound under these conditions.