Dentinal caries, as distinguished from enamel caries (here and below), arises from metabolic disturbances which can be avoided or corrected through use of diet high in all recognized nutritional essentials. Individuals vary in efficiency of utilization of these essentials. This variation may account for differences in susceptibility, to caries, in persons living under apparently similar dietary conditions. Studies of mouth flora have shown that children, after definite arrest of extensive caries which had been in progress for years, may show high counts of acid-producing bacteria, especially B. acidophilus. In children receiving prescribed diets, the incidence of such organisms has paralleled the places for lodgment of debris and the lack of oral hygiene, but not the tendency to develop caries. Chemical analysis of saliva has revealed no correlation with activity or inactivity of caries. A correlation of metabolic balance studies with status of the teeth has indicated that retentions of calcium and phosphorus tend to be definitely higher in children having no caries, or arrested caries, than in those having active caries. As caries becomes arrested, these retentions from the same diet tend to become greater.
The progress of dentinal caries, in deciduous or permanent teeth of children, is arrested within 8 to 12 weeks following establishment of a diet designed to meet all recognized nutritional needs of the normal child, including liberal amounts of protective factors. This diet is more liberal in contents of protein, calcium and vitamins than diets usually eaten by children in any socio-economic level. No medicinal agent or concentrate is employed, excepting cod-liver oil—a teaspoonful daily for each child throughout the year. Arrest of caries persists as long as such a diet is used in its entirety; reactivation follows discontinuance in whole or part. No foods have been prohibited. Sugar or starch has not been observed to favor caries, unless use of either materially diminished the amounts of ingested protective foods. Gingival enamel which had become opaque, but not disintegrated, regained its former translucency. To gauge arrest, certain cavities have been left unfilled for months or years. With arrest, exposed dentin becomes stony hard, often in 8 to 12 weeks ; the cavity does not become larger, nor seem the worse for not being filled. Histologically such teeth show sclerosis of exposed dentin after arrest has occurred, whereas little or no sclerosis is observed in actively carious portions. Serumnal calculus tends to develop as caries becomes arrested, and to remain evident and recurrent as long as the child eats the prescribed diet. With change in diet, disappearance of serumnal calculus and reactivation of caries has been noted.
The studies mentioned above related to children under treatment in the Children’s Hospital, or under observation in the Children’s Clinic of the College of Dentistry. Facilities have included competent bacteriological, biochemical and metabolic personnel and equipment, with skilled medical and dental supervision of clinical aspects. Detailed records for more than 5000 dental observations have been used in correlating data, some representing successive observations on the same patients over periods of several years. In the main, attention has been directed to caries of dentin rather than of enamel. Distinction has been made between active and arrested dentinal caries on the basis of hardness or resistance of exposed dentin to an exploring tine. Arrested caries was characterized by dentinal hardness similar to that of porcelain cement ; lesser degrees were interpreted as representing corresponding activities.
References: Numerous since 1928; chiefly in J. Am. Med. Assoc., 1928; Am. J. Dis. Child., 1929 ; J. Am. Den. Assoc., 1930, 1935 ; J. Ia. State Med. Soc., 1932 ; J. Biol. Chem., 1933 ; J. Den. Res., 1933 ; J. Am. Diet. Assoc., 1935.