The effect of perinatal TCDD exposure on caries susceptibility in rats

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD), the model com-pound of polychlorinated dibenzo-p-dioxins and furans, is a potent toxicant with the ability to hamper development. Accidental exposure to TCDD has been linked with various developmental dental aberrations in humans, and experimentally it has been shown that TCDD causes, among other defects, hypomineraliza-tion of dental hard tissues in rodents. Here, we studied the effect of very low perinatal TCDD exposure on dental caries suscepti-bility and mineral composition of tooth enamel in rats. Pregnant line C rats (rat line developed in our laboratory) were dosed 0.03– 1.0 mg/kg TCDD on gestation day 15 and allowed to give birth and nurse until weaning on postnatal day 21. The offspring were challenged with cariogenic treatment including sugar-rich diet and three inoculations with Streptococcus mutans. Control groups involved animals with or without cariogenic challenge or TCD