ABSTRACT
STATEMENT OF PROBLEM: The adhesion between titanium and ceramic is less optimal than conventional metal-ceramic bonding, due to reaction layer form on cast titanium surface during porcelain firing. PURPOSE: This study characterized the effect of titanium-ceramic adhesion after gold and TiN coating on cast and wrought titanium substrates. MATERIAL AND METHOD: Six groups of ASTM grade II commercially pure titanium and cast titanium specimens(13mm x 13mm x 1mm) were prepared(n=8). The conventional Au-Pd-In alloy served as the control. All specimens were sandblasted with 110micrometer Al2O3 particles and ultrasonically cleaned for 5min in deionized water, and dried in air before porcelain firing. An ultra-low-fusing dental porcelain(Vita Titankeramik) was fused on titanium surfaces. Porcelain was debonded by a biaxial flexure test at a cross head speed of 0.25mm/min. The excellent titanium-ceramic adherence was exhibited by the presence of a dentin porcelain layer on the specimen surface after the biaxial flexure test. Area fraction of adherent porcelain(AFAP) was determined by SEM/EDS. Numerical results were statistically analyzed by one-way ANOVA and Student- Newman-Keuls test at alpha=0.05. RESULTS: The AFAP value of cast titanium was greatest in the group 2 with TiN coating, followed by group 1 with Au coating and the group 3 with Al2O3 sandblasting. Significant statistical difference was found between the group 1, 2 and the group 3 (p.05). The AFAP values of the cast titanium and the wrought titanium were similar. However the group treated with Al2O3 sandblasting showed significantly lower value (p<.05).