EVALUATION OF MEAN SHEAR BOND STRENGTH OF ORTHODONTIC METAL BRACKETS BONDED WITH FLOWABLE COMPOSITES USED WITH AND WITHOUT INTERMEDIATE BONDING RESIN: AN IN VITRO STUDY

Abstract

 Objectives of this study were to compare the mean shear bond strength (SBS) of orthodontic metal brackets bonded to etched enamel with flowable composites used with and without intermediate bonding resin and compare its mean bracket debond time on extracted human teeth. This study was randomized controlled trial. The current RCT study was conducted at Orthodontics Department, Armed Forces Institute of Dentistry, Rawalpindi. A total of 60 extracted human acid etched premolars were randomly allocated into two groups. In Group A, bonding resin was applied on etched tooth whereas in Group B application of bonding resin was avoided. After 24 hours storage in water at 37 0C, shear bond test was performed. Results showed that mean SBS for the Group A and Group B was 12.33 MPa and 11.70 MPa respectively. Intergroup comparison between two groups using Independent sample T-test showed no statistically significant difference in mean SBS. (p=0.320) Intergroup comparison also showed no statistically significant difference in time taken for brackets to debond from tooth surface. (p= 0.52) Keeping in view the study results of mean SBS and time required for brackets to debond, flowable composites with no intermediate bonding resin could be effectively applied for orthodontic bracket bonding. Thus reducing the chair side time, chances of contamination with saliva and providing acceptable clinical bond strength.