Effect of hot chemical etching on bond strength of zirconia to resin / 华西口腔医学杂志

ABSTRACT

<p><b>OBJECTIVE</b>This study aims to evaluate the influence of hot chemical etching on short- and long-term shear bond strength (SBS) of zirconia to resin.</p><p><b>METHODS</b>Eighty zirconia ceramic slices were obtained and randomly divided into five groups based on the surface treatment to be applied--group A H2SO4/(NH4)2SO4 hot solution etching + application of Clearfil; group B HF/HNO3 hot solution etching + application of Clearfil; group C H2SO4/HF/HNO3 hot solution etching + Clearfil; group D alumina sandblasting + application of Clearfil; group E tribochemical silica coating + application of silane coupling agent. Eighty composite cylinders were bonded to pretreated ceramic slices using a bis-GMA-based resin cement. Specimens in each group were divided into two fractions the first half received 24 h water storage, and the second half received 40 d water storage. Then, SBS tests were conducted. Morphological analysis of sandblasted alumina and hot chemical-etched zirconia surfaces were performed by scanning electron microscopy(SEM).</p><p><b>RESULTS</b>Group E displayed the highest SBS before artificial aging, and no statistical difference was found among the other groups. After 40 d water storage, groups A, B, and E showed significantly higher SBS than groups C and D. SBS increased significantly after artificial aging in groups A and B. No significant variations were found before and after artificial aging in the other groups.</p><p><b>CONCLUSION</b>The experimental hot chemical etching solution provides enhanced bonding for zirconia than sandblasting, and the bond strengths remain stable after artificial aging.</p>