In vitro comparison of shear bond strength of transbond XT and heliosit orthodontic as direct bracket bonding adhesives

ABSTRACT

Heliosit Orthodontic was developed to ease the bonding procedure of orthodontic attachments by eliminating the need for primer application both on the bracket base and the etched tooth surface. The aim of this study was to determine the shear bond strength of Heliosit Orthodontic and then compare it with the control group of Transbond XT. The study consisted of two groups A and B of 80 human premolar teeth each bonded with mesh based metal brackets. The bonding agent used in group A was Transbond XT and that of group B was Heliosit Orthodontic, Every effort was made to control the cofounding variables including light tip distance, force of application of bracket, storage of teeth before and after bonding and orientation of bracket in the acrylic block this was followed by debonding of the brackets by shearing in a universal testing machine. It was found that the mean shear bond strength of Transbond XT was 25.5 MPa and that of Heliosit orthodontic was 10.54 MPa. The t-test revealed that there was a significant difference between the shear bond strength of the two groups. In conclusion the bond strengths of both the composites tested were greater than the recommended values of Reynolds for the composites to be clinically useful. It is recommended that the bond strength and the viscosity of the Heliosit Orthodontic be increased for it to be clinically as efftctive as Transbond XT