Determination of the flouride concentration profile in tooth enamel using a nuclear resonance technique

The ¹⁹F (p,αγ) ¹⁶O reaction has been used to measure the concentration profile of fluorine in tooth enamel. By observing the characteristic 6.13 MeV gamma ray with a high resolution Ge(Li) detector, the fluorine concentration was measured to a depth of 2.1 μm in teeth treated with K₂ZrF₆, NaF and acidulated fluorophosphate. The differential depth resolution was better than 0.1 μm at the surface of the teeth. Additional information on the average elemental concentration within the first 2 μm was obtained by observing the characteristic X-ray produced by 1.8 MeV protons. The exploratory data developed in this study have indicated that the highest uptake of fluoride was achieved through the application of K₂ZrF₆.