The bonding of a polymeric fissure sealant to topical fluoride-treated teeth

The tensile bond strength of a polymeric fissure sealant to enamel treated with a variety of topical fluorides was determined. Application of acidulated phosphate fluoride solutions (APF) prior to and after acid etching reduces the tensile bond strength of Nuva Seal from 36-6+/-9-0 kg/cm2 to 4-9+/-3-3 kg/cm2 and 23-8+/-6-3 kg/cm2 respectively. The treatment of the etched enamel with freshly prepared 8% stannous fluoride solution prior to Nuva Seal application significantly increases the tensile bond strength to 55-7+/-17-1 kg/cm2. It is recommended that clinical procedures such as the application of fissure sealants, acid etch composite restorations and the direct attachment of orthodontic brackets, all of which involve etching of the enamel, should not be precedded by the topical application of APF solutions.