Self-adhesive restoratives as pit and fissure sealants: a comparative laboratory study

Abstract

OBJECTIVES: To evaluate the properties of self-adhesive restorative materials used as sealants in comparison with sealants with hydrophobic or hydrophilic monomers.
METHODS: The self-adhesive materials tested were Fusio (FS) and Vertise-Flow (VF) and the sealants Embrace Wetbond (EM/hydrophilic) and Helioseal-F (HS/hydrophobic). The properties tested were: (a) degree of cure (%DC, n: 5, ATR-FTIR), (b) extent of oxygen inhibition (n: 5, transmission optical microscopy), (c) flow (n: 5, ASTM D-4242 method), (d) hardness (VH0.2kp/10s dry/1w in water), (e) adaptation, microleakage and fissure penetration (n: 10, 1% fuschin dye, reflection optical microscopy and ESEM). Statistical analysis was performed by one-way ANOVA plus Tukey test (a-d), Fisher's exact and Kruskal-Wallis plus Tukey tests (e) at a 95% confidence level.
RESULTS: VF showed the highest %DC(76.1) followed by HS(68.7) and EM(61.3), FS(59.2). HS demonstrated the highest extent of oxygen inhibition (23μm vs. 13-10μm of the rest). EM and HS exhibited the greatest flow, followed by FS and VM. The VHN(0.2kp/10s) ranking before and after 1week water exposure was FS≥VF>EM≥HS. Water storage increased VF and reduced HS values. The lowest adaptation and microleakage scores were found in HS. FS and VF after alumina sandblasting showed the worst adaptation and leakage scores, that were improved after acid-etching. Improved fissure penetration was found in HS, EM and FS, VF after acid-etching.
SIGNIFICANCE: Although the self-adhesive materials presented improved setting characteristics, their low flow affected fissure penetration capacity. When combined with enamel acid-etching, adaptation and microleakage scoring were substantially improved in comparison with enamel sandblasting. The sealant with the hydrophobic monomers demonstrated the best sealing characteristics.