Advances in Dental Research, Vol 8, 239-245, Copyright © 1994 by International & American Associations for Dental Research
Saliva stimulation and caries prevention
W. M. Edgar, S. M. Higham and R. H. Manning
Department of Clinical Dental Sciences, School of Dentistry, Liverpool, England.
The protective role of saliva is demonstrated by the rampant caries seen in
human subjects with marked salivary hypofunction, and in desalivated
animals. In normal cases, however, the relationship between saliva flow and
coronal or root caries experience is doubtful, and to examine the concept
that stimulation of saliva might have protective effects against caries,
one must look beyond a simple correlation between caries and flow rate.
Protective properties of saliva which increase on stimulation include
salivary clearance, buffering power, and degree of saturation with respect
to tooth mineral. These benefits are maximized when saliva is stimulated
after the consumption of fermentable carbohydrates, by reducing the fall in
plaque pH leading to demineralization and by increasing the potential for
remineralization. Plaque acid production is neutralized, and experimental
lesions in enamel are remineralized, when gum is chewed to stimulate saliva
after a carbohydrate intake. The pH-raising effects are more easily
explained by the buffering action of the stimulated saliva than by
clearance of carbohydrates. The remineralization action depends upon the
presence of fluoride. These findings suggest that the protective actions of
saliva can be mobilized by appropriate salivary stimulation, and that in
addition to established procedures such as tooth cleaning and fluoride
regimens, eating patterns which lead to saliva stimulation to increase the
potential for saliva protection might be included in recommendations for
caries prevention. Confirmation of this concept in clinical tests is
required.
