Inhibition of experimental caries by oat hullss

Abstract

THERE is agreement in previous reports that inhibition of experimental caries is accomplished by adding oat hulls to a cariogenic diet. This effect is demonstrated in two studies using the cotton rat (TAKETA and PHILLIPS, 1957; VOGEL, THOMPSON and PHILLIPS, 1962). Likewise in the cotton rat, rice, pecan, peanut and cottonseed hulls inhibit caries (MADSEN and EDMONDS, 1962, 1963). There is but one report pertinent to the white rat in which oat hulls inhibited caries. In this study the diet contained mainly yellow corn grits and ground yellow corn, ingredients productive of occlusal surface caries (BUTTNER and MULLER, 1959). None of these observations involve smooth surface carious lesions. It appeared of interest to present additional data relative to the white rat using diet 585 which produced mainly occlusal fissure caries, and 374 which induced only smooth surface caries. The results are discussed also in relation to the cariostatic effect of organic phosphates. The essential components of diet 585 were whole milk powder, 30 per cent; corn grits, 42 per cent, and cane sugar, 25 per cent (STEPHAN et al., 1952). Diet 374 contained ground dry bread, 76 per cent, and commercial cerelose, 18 per cent, as essential ingredients (MCCLURE, 1960). Finely ground oat hulls were added as 15 per cent or 8 per cent of the entire diet. Weanling Sprague-Dawley rats of both sexes were housed two per screen-bottomed cage, ate and drank distilled water ad Ii&turn, and were on experiment 70-90 days. The essential data are presented in the table. While reduction in caries varied in these four experiments (Table l), there seems little doubt that the oat hulls were responsible for a significant inhibition of caries, indicated particularly by the reduction in caries severity scores. In all four trials the number of carious teeth was also reduced. In one study (exp. 2), the oat hulls reduced the number of carious rats 755 per cent. In the three other studies, this incidence was reduced approximately 20.0 per cent. Thus it appears that oat hulls proved effective in inhibiting the smooth surface type of caries produced by diet 374 and in agreement with previous studies, reduced the occlusal caries produced by diet 585. The oat hulls were finely ground, indicating as has been reported by TAKETA and PHILLIPS (1957) that their physical state was not the factor in their cariostatic