Analysis of plaque formation susceptibility in ODUS/Odu

Abstract

Since 1972, we have bred naturally occurring gingivitis rats (ODUS/Odu) in our laboratory. They were originally derived from the Wistar-Kyoto strain, and are now in the 84 th generation. The animals were given a commercial powdered diet and tap water ad libitum from five weeks after birth. They had heavy plaque formation on the mandibular incisors and developed both periodontal pockets and gingivitis. We investigated plaque formation susceptibility in these rats using ODUS/Odu and ACl/NJcl, both of which were fed a commercial powdered diet. We obtained first filial generation (F₁) rats, second filial (F₂) rats and backcross rats, and judged their plaque index by the method of Ito et al.
The F₁ rats did not exhibit plaque formation throughout the experimental period. Plaque formation was seen in 50% of the F₂ rats, and 87.4% of the backcross rats. These results suggested that plaque formation susceptibility may be regulated by three autosomal recessive genes.Shika Igaku(J Osaka Odontol Soc) 2003 Dec; 66(4): 377-383.