THE EFFECT OF 2 SUCROSE DIETS ON FORMATION OF DENTIN AND PREDENTIN INGROWING RATS

The effect of two high-sucrose diets on dentinal caries, dentin format ion, and the predentin width was studied in Sprague-Dawley rats. Rats were weaned at the age of 3 weeks and for 4 weeks fed a non-cariogenic commercial rat food (R36) for control, a high-sucrose Stephan-Harris (S-H) diet, or a new high-sucrose (sR36) diet in which most of the bar ley and wheat flour of the control R36 diet were replaced by sucrose. The areas of dentinal caries, the areas of dentin formation, and the w idth of predentin and dentin were quantified. Both high-sucrose diets induced dentinal caries, and both reduced dentin formation and increas ed the width of predentin compared with the control diet. Moreover, ra ts fed the S-H high-sucrose diet showed significantly greater progress ion of caries and reduction of dentin formation relative to rats fed t he new high-sucrose diet, sR36. The high-sucrose diet thus was a subst rate for caries-inducing microbes and a significant, but possibly not the exclusive, substrate for host modulation of odontoblast function.