Sealing potential of a self-adhesive fissure sealant

Objectives: To test the null hypothesis that phosphoric acid does not improve the sealing ability of a new self-adhesive fissure sealant. Methods: 15 extracted molars stored in 0.4% chloramine T for 1 month were cleaned with pumice and randomly assigned to 3 groups (n=5): (1) Enamel Loc (ELOC, Premier Dental), a self-adhesive sealant applied as per manufacturer's instructions; (2) Enamel etched with 35% H₃PO₄ for 15 sec followed by the application of ELOC; (3) Enamel etched with 35% H₃PO₄ for 15 sec followed by the application of Clinpro (3M ESPE) as the control group. Teeth were thermocycled for 1,000 cycles (5-55^oC), isolated with nail polish except for the occlusal surface, left in 50% ammoniacal silver nitrate for 24h at 37^oC, then photo-developer for 8h. Each tooth was sectioned BL in four 1.0±0.2 mm thick slices. Silver infiltration was measured under a digital stereo microscope at X20 in rankings from 0 (no silver infiltration) to 3 (silver infiltration to the full fissure depth). Further analyses were carried out with backscattered FESEM. Medians (M) were analyzed with nonparametric tests (Mann-Whitney and Median tests, P<0.05, superscript letters). Results: