Methodology for testing the micro-shear bond strength of dual-cure resin cement to pretreated zirconia surface

The aim of this study was to evaluate the micro-shear bond strength of dual-cure resin cement to zirconia surface pretreated with different tech-niques. Twenty-four sintered Y-TZP zirconia discs (Kuraray Noritake Dental Inc.) with a diameter and thickness of 11.8 mm and 5.0 mm, respectively, were used for the present study divided into four groups according to the pre-treatment procedures: 1) control group without any pretreatment; 2) MDP (10-methacryloyloxydecyl dihydrogen phosphate) primer treated; 3) sandblasted with 50 & mu;m Al2O3 at 2 bar, and 4) MDP treated in combination of sandblast-ing. The micro-shear bond strength was measured by applying an axial load on the bonded interface using a universal testing machine LMT 100 (LAM Technologies, Italy). An original methodology of elaboration of specimens for testing was developed. Statistical analysis was performed with SPSS 11.5 Inc., Chicago, IL, USA, Excel 7.0 VB. One-way analysis of independent samples (ANOVA) was used to analyze the data with the level of significance p < 0.05. The Bonferroni's multiple comparison test was used to reduce the instance of false positive results. The impact of surface pre-treatment procedures on bond strength was studied and the best combination was revealed.