Single oral acute fluoride exposure causes changes in cardiac expression of oxidant and antioxidant enzymes, apoptotic and necrotic markers in male rats.

Several studies have shown that acute fluoride (F(-)) exposure impairs cardiac function, but the molecular mechanism is not clear. In order to study this, male Wistar rats were treated with single oral doses of 45 and 90 mg/kg F(-) for 24 h. A significant accumulation of F(-) was found in the serum and myocardium of experimental rats. F(-) treatment causes myocardial necrosis as evident from increased levels of myocardial troponin I, creatine kinase, lactate dehydrogenase and aspartate transaminase. In addition, F(-) induces myocardial oxidative stress via increased reactive oxygen species, lipid peroxidation, protein carbonyl content and nitrate levels along with decreased in the levels of enzymatic (superoxide dismutase 2, catalase, glutathione peroxidase and glutathione s transferase pi class) and non-enzymatic (reduced glutathione) antioxidants. Notably, F(-) triggers myocardial apoptosis through altered Bax/Bcl2 ratio and increased cytochrome c, caspase 3p20 and terminal deoxynucleotidyl transferase dUTP nick end labeled positive cells. An increased cardiac expression of Nox4 and p38α MAPK in F(-) treated rats indicates the oxidative and apoptotic damage. Moreover, ultra-structural changes, histopathological and luxol fast blue staining demonstrates the degree of myocardial damage at subcellular level. Taken together, these findings reveal that acute F(-) exposure causes cardiac impairment by altering the expression of oxidative stress, apoptosis and necrotic markers.

Controlling the fluoride dosage in a patient with compromised salivary function.

BACKGROUND: High-concentration topical fluorides are used commonly to with compromised salivary function due to irradiation and chemotherapy. CASE DESCRIPTION: The authors describe a 50-year-old man with previously treated cancer who was using tray-applied topical fluoride gel. He complained of gastric symptoms, difficulty in swallowing, leg muscle soreness and knee joint soreness. A computed tomographic scan revealed thickening of the esophageal walls. An upper endoscopy revealed abnormal motility. The motility test indicated high-amplitude peristalsis and hypertensive lower esophageal sphincter, and urine testing indicated high levels of systemic fluoride. The patient's fluoride regimen was altered, and within a short period his urinary fluoride levels returned to normal and his symptoms resolved. CLINICAL IMPLICATIONS: Clinicians prescribing home-applied high-concentration fluorides need to be cognizant of the symptoms of fluoride toxicity, carefully monitor the patient's compliance with the treatment regimen, and adjust the dosage or mode of application to control the total ingested dose of fluoride.

Practitioner's guide to fluoride.

The current health care trend is to provide evidence-based recommendations and treatment. Many literature reviews have shown fluoride's effectiveness against caries. The current use of fluoride in the prevention of dental caries is based on community, professional, and individual strategies. Personalized fluoride regimens should include a risk analysis and a review of the patient's current fluoride exposure. The future of fluoride may be found in its slow release and retention in the oral cavity through various modalities. Because of the many uncertainties still associated with fluoride, further research is needed.

Systemic fluoride. Sources, amounts, and effects of ingestion.

Fluoride may be ingested from a variety of sources, including many foods and beverages. Fluoride intake varies greatly among individuals and is dependent on dietary constituents and use of fluoride products. Although ingestion of toxic amounts of fluoride is rare, the prevalence of dental fluorosis has increased in North America, suggesting that the levels of fluoride ingestion need to be closely monitored. Care should be taken to avoid excessive ingestion of fluoride dentifrice by preschool-aged children by placement of a small, pea-sized quantity on the tooth-brush. Dietary fluoride supplements should be considered a targeted, preventive procedure only for those at elevated caries risk, and before prescribing them, careful consideration should be given to other fluoride sources, including home and child-care water supplies, foods, and beverages.