Work of adhesion of resin on treated lithia disilicate-based ceramic

Objective. This study is to test the hypothesis that chemical etching and silane coating of a ceramic surface will influence the work of adhesion (W-A) of adhesive resin to dental ceramic. Methods. A hot-pressed lithia disilicate-based ceramic was used as a model material to investigate the influence of probing media and surface treatments on W-A using a dynamic contact angle analyzer. Eighty ceramic specimens were randomly divided into eight experimental groups and treated as follows: (1 and 3) as polished; (2 and 4) etched with 9.5% hydrofluoric acid (HF) for 1 min; (5) etched with 4% acidulated phosphate fluoride (APF) for 2 min; (6) silane coated; (7) etched with HF for 1 min and silane coated; (8) etched with APF for 2 min and silane coated. Advancing and receding contact angles (theta(a) and theta(r)) were measured using high purity water (gamma = 72.6 mN/m) for groups 1 and 2, and a liquid resin (gamma = 39.7 mN/m) for groups 3 - 8 as probing liquids. Results. The liquid resin medium yielded a lower W-A than water. Silanization produced a significantly lower W-A (p < 0.001) than non-silanated surfaces. Etching atone consistently yielded a greater W-A for all surface treatments (p < 0.001). Significance. The silanated ceramic surface exhibited a tower surface energy and did not enhance bonding to the liquid resin by work of adhesion. (C) 2003 Academy of Dental Materials. Published by Elsevier Ltd. At[ rights reserved.