Fluoride retention following topical application of a new APF foam.

The oral retention of fluoride (F) following the topical application of a newly developed APF foam was compared with a conventional APF gel. Twenty adults aged 16-26 years participated in the study. Ten of the subjects received the F foam and gel treatments, on separate occasions, with a saliva ejector while another 10 subjects received the same treatment without saliva ejector. Approximately 4 g of the gel, and 0.9 g foam, were dispensed for each treatment. The amounts of fluoride applied, recovered from the mouths, and retained in the mouth were calculated for each treatment.