THE INFLUENCE OF ORTHODONTIC BRACKET BASE DIAMETER AND MESH SIZE ON BOND STRENGTH

Abstract

Introduction- To enhance the retention of the adhesive to the metal base of orthodontic brackets, various chemical and mechanical retentive designs have been suggested.
Methodology- A total of 40 extracted human molars were collected and stored in a solution of 0.1% (wt/vol) thymol. The criteria for tooth selection included intact buccal enamel, no history of any pretreatment with chemical agents, eg, hydrogen peroxide, no cracks due to the presence of the extraction forceps, and no caries. Two types of brackets were used in this study. Twenty Ovation metal bracket series with a double-mesh base (Super-mesh) and an 81.50 gauge.
Results- The descriptive statistics for the two bracket types compared are presented in Table 2. The mean shear bond strength was 5.2 ± 3.9 MPa for the double-mesh brackets and 5.8 ± 2.8 MPa for the single-mesh brackets. The t-test comparisons indicated that these values were not significantly different from each other. The ARI scores comparison indicated that both bracket types had similar bracket failure modes and were not significantly different from each other.
Conclusion- The results indicated that the single- and double-mesh bracket bases evaluated in this study provided comparable shear bond strengths and bracket failure modes.