An in vitro study of the distribution of silver and fluoride following application of 40 per cent silver fluoride solution to dentine

An in vitro test system involving application of 40 per cent silver fluoride solution to prepared cavities of moderate depth in extracted teeth failed to demonstrate the passage of significant amounts of fluoride into the dental pulp, despite a very high concentration of fluoride (100 000 ppm) in the applied solution. The test system used may not be conducive to quantitative investigation of ionic transfer because of disruptions to pulp circulation and fluid flow through dentine following tooth extraction. For this reason, the results are inconclusive as to whether or not application of 40 per cent silver fluoride as a cavity varnish or liner, and its use in the 'atraumatic' technique for treating deep caries, can be considered safe clinical procedures.