Oral effects of sugars and sweeteners.

Increasingly, sweeteners are being used in the diets of caries-prone individuals to reduce sugar intake. Such substitution deprives the bacteria in the dental plaque of the sugars many of them use to produce the acids that cause demineralization of tooth tissue and development of the caries lesion. Sweeteners are particularly effective replacements for dietary sugars because they also stimulate the flow of saliva which can, through several mechanisms, prevent demineralization and even bring about remineralization of already demineralized enamel, dentine or cementum. More saliva means that more of its nitrogen-containing substances will reach the dental plaque where they can be degraded by plaque bacteria and thus produce base and the alkaline conditions that are conducive to a shift from tooth demineralization to tooth remineralization. At the same time, the additional saliva brings to the plaque more calcium and phosphate ions, the necessary ingredients for the remineralization process. At alkaline pH, saliva also provides a source of easily solubilized calcium phosphate that, in association with salivary carbohydrate protein, becomes part of the dental plaque. Because it is dissolved by acid more easily than is the calcium phosphate of the tooth, plaque calcium phosphate acts as a substitute for the tooth tissues when periods of acid attack occur following sugar ingestion. It is proposed that diagnostic tests be developed that can conveniently determine the acid-base and demineralization-remineralization potentials of different dental plaques and that these tests be used to determine the extent to which sugars in the diets of caries-active individuals be replaced with sweeteners.