Enamel biopsies for F analysis were performed on the mesial, buccal, distal and lingual surfaces of contralateral pairs of premolars extracted from 104 10- to 14-year-old children. Five successive etchings, each of 5 s duration, were carried out on the mesial and buccal surfaces with 2 M HClO4, and 5 successive etchings, each of 2 s duration, were performed on the distal and lingual surfaces using 0.5 M HClO4. The F concentrations were adjusted to standardized depths and the F concentrations at individual and cumulative etch depths determined. The caries experience of the children was expressed as filled teeth (FT) or filled surfaces (FS). Highly significant correlations (p = 0.0001) between age and FT and FS were obtained. No significant relationship between dental caries experience and enamel F concentration was established in the present study except for a significant correlation between dental caries and the enamel F concentration in the outermost 10 μm on the buccal aspects of the premolar teeth