Research on residual alveolar bone in fluorosis rats

Objective: To evaluate the effect of fluorosis on residual alveolar bone of rats. Methods: Sixty SPF rats aged 45 days were randomly divided into four groups: control group, low-dose group, medium-dose group and high-dose group. Rats in the four groups took normal food and drank distilled water, sodium fluoride of 50 mg/L, 100 mg/L and 200 mg/L, respectively. All molars in left maxillary bone were extracted after 2 months. Each rat in the four groups was killed at one or two month after tooth extraction. The mandible residual bone of each rat was removed to evaluate the expression of alkaline phosphatase (ALP) with histochemical staining. Results: The results demonstrated that the positive expression of ALP was significantly elevated with the increase of osteoblasts in control group and low-dose group, but decreased with the decline of osteoblasts in medium-dose group and high-dose group. The decline of the counted number of positive cells showed that the expression significantly lowered in high-dose group. Compared with that at one month, the counted number of positive cells at month two after tooth extraction was significantly lower in all drug groups. Conclusion: Chronic fluoride poisoning accelerates the damage of alveolar bone in rats.