Acid is a potent factor in destruction of tooth structure, in caries or erosion. Acids decalcify enamel, robbing it of basic elements. Acids in excess on specific dental areas are there destructive. Acid-yielding foods are important factors in interproximal caries. Elimination from the mouth of acid-yielding residual materials reduces caries and erosion. Addition of mineral salts to saliva reduces the destructive action of acids in caries and erosion, and provides chemical combinations that replace some of the lost structure—remineralizes decalcified areas. The remineralizing formula of Andresen dissolves in saliva, combines with acid exudate, and permeates and calcifies porous enamel- areas caused by erosion. This recalcification or remineralization reduces sensitivity in eroded areas, and checks rampant caries in areas of hypocalcification. This principle of remineralization may be helpful in hardening poorly calcified teeth, and in correcting posteruptive fissures. Dentifrices leave residues between teeth. Each persists despite careful rinsing, and acts as a nucleus to which food particles adhere for further fermentation and acid formation. Andresen’s effervescent dentifrice does not deposit such a residue—excess, if left in the interproximal spaces, is an advantage owing to prolonged action by gradual solution in saliva, leaving the interproximal spaces clean.
Recalcification of bones in the human body, by intake and assimilation of calcium, has been helpful in rickets and other conditions of decalcification, including teeth whose calcium content is below par. Calcium has been prescribed as a corrective for soft or brittle teeth. Among the outstanding clinical evidences of tooth decalcification is erosion. Irritated periodontal tissues cause acidity of gin‑gival exudate, which erodes the tooth surface on which it concentrates. Saliva as an acid medium does not cause erosion, otherwise erosions would occur on all teeth bathed by it. Use of alkalies to reduce oral acidity is contraindicated, because mouth fluids cannot be maintained in a high state of alkalinity for any length of time. Alkalies used for this purpose depress salivary secretion. Reduction in flow of saliva increases concentration of acid exudates, and promotes tooth destruction. Recalcification or remineralization of eroded tooth-surfaces, by use of irradiated inert oils over a prolonged period, promotes unhealthy calcium deposition in some organs. Correction of irritating factors lessens acid production around teeth.
Reference: Den. Items Int., 1939.