Comparative Evaluation Of Surface Treatments On The Shear Bond Strength Of Low Fusing Porcelain To Titanium Alloy: An In Vitro Study

Abstract

Aim:  Aim of this study was to evaluate and compare the effect of various surface treatments on the shear bond strength between a low-fusing porcelain and titanium alloy.Material and methods: A total 40 specimens of titanium alloy were prepared according to ISO standards 9693; TR 11406 (5mmx4mmx4mm) in a milling lathe. The samples were equally divided into 4 Groups. Group A was not subjected to any treatment and was considered as control.  Group B were subjected to sandblasting with 110 μm Al₂O₃ particles. Group C were subjected to laser etching and Group D were coated with AlN. The bonding agent was applied on all samples and fired according to the manufacturer’s instructions. Low-fusing porcelain was fired onto the surface of the specimens. Later the shear bond strength were evaluated using a Universal testing machine. The obtained data was analysed using One way ANOVA among the various groups and Multiple Group comparison was done using Post Hoc Tukey’s HSD Test. The failure modes were also evaluated under Scanning Electron Microscope (SEM). Results:  The highest mean bond strength value was found in the sandblasted group (34.01 ± 1.05 MPa) followed by the laser group(27.16 ± 1.1 MPa), the AlN group(15.02 ± 0.93 MPa), and then control group(15.04 ±0.82 MPa). There was a significant difference in bond strength for sandblasted group and laser group when compared to the control group (P<001). AIN surface treatment provided no beneficial effect to the Titanium -Ceramic bond strength compared to untreated specimens(P=1)                    

SEM analysis indicated a predominance of cohesive failure in sandblasting and laser group. Conclusions: Among the three surface treatments, sandblasting showed highest bond strength between titanium and ceramic. There was no significant difference between laser etching and sand blasting surface treatment. Clinical significance : For improving the bonding of low fusing porcelain to Titanium alloys Sand blasting and Laser etching can be employed.