Shear bond strength and microleakage results for three experimental self-etching primer compositions for pit and fissure sealing

OBJECTIVES: This in vitro study evaluated the shear bond strength (SBS) and microleakage of three experimental self-etching primers for pit and fissure sealing. MATERIALS AND METHODS: The material used three formulations of an experimental fissure primer (EFP) applied without phosphoric acid etching (EFP-1/EFP-2/EFP-3) and one control group with sealant application after 30 s of acid etching. Four groups of sealants (n = 40 specimens/group) were tested for SBS, and a failure analysis was conducted after 1-day water storage, 3-month water storage, and 5000-fold thermocycling. In addition, microleakage was tested. RESULTS: The SBSs of the EFPs (range 8.2 MPa (standard deviation 4.2) to 15.4 MPa (5.4)) were generally significantly lower than those of conventional fissure sealing (range 15.6 MPa (4.4) to 19.1 MPa (6.2)). The SBS of EFP-3 was better than that of the EFP-1 or EFP-2 formulations. Microleakage was significantly lower in the control group (1.1 %) than in the EFP-1 (3.8 %) and lower than in EFP-3 (7.7 %) group. In the (multiple) linear regression analysis, material and aging significantly influenced SBS. CONCLUSIONS: The SBS of EFP-3 was 15 to 32 % lower than it was for the corresponding controls. CLINICAL RELEVANCE: The SBS is lower, but the main potential benefit of this new approach is a reduced application time in clinical practice.