Evaluation of Micro Tensile Bond Strength between Surface Treated Zirconia and Ceramic: An Invitro Study

Abstract

Purpose:The purpose of the present study was to compare the micro tensile bond strength at the core – veneer interface of zirconia restorations after using Al₂O₃ airborne particle abrasion, chemical etching with 5:5 mixed solution of hydrofluoric acid and nitric acid and both sandblasting and chemical etching. MATERIALS AND METHODS:-A total of 60 specimens of sintered zirconia ceramic of size 10×5×5 mm were used for the experiment. Sixty samples were randomly divided into four groups according to the surface treatment method used. Group 1(control): CAD/CAM milled surface without any surface treatment. Group 2: Al₂O₃ airborne particle abrasion was performed using a sandblasting machine with 110µ particle size. Group 3: Chemical etching using 5:5 mixed solution of hydrofluoric acid and nitric acid for 2 hrs. Group 4: sandblasting with Al₂O₃ particles and chemical etching with 5:5 mixed solution of hydrofluoric acid and nitric acid. Sectioning of specimens was done until 1×1×14 mm³ microbars were obtained. The microbar with metal bars was attached to the opposing arms universal testing machine. RESULTS:-The highest mean micro tensile bond strength value was measured in the sandblasting, and chemical etching group (46.4 MPa), and the lowest value was measured in the control group (30.84 MPa). CONCLUSIONS:-There is a significant increase in the mean micro tensile bond strength between experimental groups and the control group. There is also a considerable increase in value in group 4 from groups 2 and 3. But there is no significant difference between group 2 and group 3.