“…Fluoride rinses and tablets have, however, reduced caries without significant increase in en amel fluoride [Shern et al, 1977;Aasenden et al, 1972], Consequently, the importance of fluoride content in enamel has recently been questioned, and it has been suggested that fluoride content in local environment surrounding the tooth may be more im portant [Fejerskov et al, 1981;Larson, 1977]. This may be also important with fluoride varnishes, since fluoride from the varnish is released slowly, and the fluoride content of oral fluids and plaque may thus be increased for a longer time.…”