Fracturing of the Molar Teeth in Caries-Susceptible and Caries-Resistant Albino Rats (Rattus Norvegicus)

Abstract

Resistance to mechanical breakage was tested by dropping an aluminum rod upon the cusps of the lower molars of caries-susceptible and caries-resistant rats. The lower molars of the resistant 60-day-old animals showed the greater resistance to mechanical fracturing. Unexpected dental caries appeared in some of the susceptible rats fed on the diet containing rice flour, before they were 60 days old. Staining of the lower molars of susceptibles suggested a high incidence of microscopic caries. Very few fractures were observed in the lower molar teeth of these 60-day-old susceptible rats, though dental caries appeared in nearly half of them. Therefore, fracturing was probably not an important factor in initiating dental caries in our rats.