OBJECTIVEThis study aims to investigate the effects of post-cure heat treatment (PCHT) on the bond strength of Ceramage composite resins for titanium casting using different surface treatments.

METHODSMetal specimens (n=30) were randomly divided into following five groups: polishing (group A), sandblasting (group B), acid etching after sandblasting (group C), PCHT after sandblasting (group D), and PCHT after sandblasting and acid etching (group E). The specimens were then processed and coated with Ceramage composite resins according to the grouping. After treatment, the shear bond strengths and microhardness of the specimens were evaluated. The fracture surface morphology of the titanium-Ceramage composite resin was observed using a scanning electron microscope.

RESULTSThe shear bond strengths of groups A to E were (5.92 +/- 0.54), (10.25 +/- 0.55), (14.97 +/- 0.88), (14.41 +/- 0.63), and (19.95 +/- 0.52) MPa, respectively. No statistical difference was found between groups C and D, whereas the rest of the groups showed statistically significant differences (P < 0.01). Visible polymerization residues were found on titanium porcelain metal surface of groups B to E. The microhardness values of groups D and E were higher than those of groups B and C (P < 0.05).

CONCLUSIONPCHT significantly improves the bond strength and surface microhardness of Ceramage composite resins for titanium casting.