EFFECT OF SODIUM FLUORIDE ON BIOMECHANICAL AND HISTOMORPHOMETRIC BONE PARAMETERS: IDENTIFICATION OF VARIABLES THAT DETERMINE THE FRACTURE LOAD IN NaF-TREATED RATS

Osteoporosis and tooth decay are very significant public health problems. For their treatment, sodium fluoride (NaF) and monofluorophosphate are the drugs containing fluoride (F) most commonly used. Disorganization of bone tissue and the presence of inflammatory foci observed when NaF is administered could be the cause of the lack of effectiveness of F in the treatment of osteoporosis. The aim of this work was to evaluate the effect of different F doses on biomechanical and morphometric properties of trabecular and cortical bone. Twenty-four Sprague-Dawley rats were divided into 4 groups (n = 6/group): NaF20, NaF40, NaF80, which received orally 20, 40, or 80 mu mol NaF/lOOg bw/day for 30 days. The Control group received water without NaF. After treatment, tibias and femurs were extracted. Histopathological and histomorphometric parameters were evaluated in the left tibia. In the right tibia, bone mineral density (BMD) and cortical parameters were determined. The femurs were used for biomechanical tests to evaluate trabecular and cortical bone properties. Results are expressed as mean plus or minus SEM and differences were considered significant if p