Fluoride concentration in whole saliva and separate gland secretions in schoolchildren after intake of fluoridated milk.

Fluoride concentration in whole saliva and in separate gland secretions was studied after a 7-day fluoridated milk regimen (1mg F per day) in 12 healthy schoolchildren aged 10-13 years. A 2-week fluoride-free run-in period preceded the tests in order to establish the endogenous baseline levels. Unstimulated and stimulated whole saliva and stimulated parotid and submandibular-sublingual saliva were collected at 1, 3, 6, 12 and 24h after F-milk ingestion, and fluoride concentrations were determined with an ion-selective electrode. Typical time-dependent excretion curves were obtained in all collected secretions. The fluoride levels were significantly elevated 1 and 3h in whole saliva and up to 6h in the gland secretions after intake of fluoridated milk when compared to baseline values. When acid-stimulated, the submandibular-sublingual glands were the major contributors of fluoride in the oral cavity. In conclusion, the results of this study demonstrate that fluoride ingested with milk is excreted through the salivary glands, indicating that the bioavailability of fluoride from milk equals that of other vehicles.