Comparison of two Scoring Methods for Root Surface Caries in Hamsters

Abstract

The aim of this investigation was to compare two methods of scoring root surface caries in hamster teeth. The experimental material was mandibles from hamsters which had been infected with Actinomyces viscosus, fed a caries-promoting diet, and received either 0, 1, 10, or 25 ppm fluoride in the drinking water during an 18-week experimental period (Stookey, 1986). Root surface caries on the lingual surfaces of mandibular first molars was scored according to the grid method of Doff et al. (1977) and by the quantitative planimetric method of Firestone et al. (1986). Data from both methods confirmed that 25 and 10 ppm fluoride were significantly more caries-inhibitory than 1 ppm fluoride, which, in turn, significantly reduced root surface caries compared with the 0 ppm control group. Correlation coefficients for caries scores (0.92) and ranking of the scores (0.88) for each animal between the two methods were highly significant (p < 0.0001). The planimetric measurement of root surface caries in hamsters was as sensitive as the grid-scoring method.