An enamel biopsy method has been developed which involves polishing off about 0.2 mg enamel from accessible surfaces of single teeth. This is accomplished with a rotating midget felt cone impregnated with silicon carbide. The cone is coated with glycerine which traps and forms a slurry with the ground enamel particles. The slurry and the felt cone are transferred to a plastic test tube and subjected to F and Ca analysis, employing an F electrode and atomic absorption spectrophotometry. Findings showed that the levels of F in intact anterior teeth from the same individual usually were similar, and that mean concentrations varied from 400 to 2500 ppm in the anterior teeth of the different persons studied. A second biopsy taken from the same tooth surface showed lower concentrations of F than the first biopsy, confirming previous findings in extracted teeth of F gradient in enamel. It was calculated that a layer of enamel between 1 and 2μ in thickness usually was removed by the biopsy procedure. Patients have no objection because the treatment is similar to a pumice prophylaxis and produces a highly polished surface. The biopsy procedure is harmless to the patient, takes little chair time and is simple to perform.