Bond Strength and ARI Evaluation of Anti-Cariogenic Bonding Materials

Objective: With the increased potential for enamel demineralization during orthodontic treatment, a bonding material with anti-cariogenic properties and clinically acceptable bond strength could have a profound impact upon orthodontics. The purpose of this study was 1) to determine if the bond strength of anti-cariogenic orthodontic bonding materials is clinically acceptable, and 2) to evaluate the enamel-adhesive-bracket interface after bracket debonding. 

Method: This study’s sample consisted of sixty extracted human premolar teeth randomly assigned to 6 groups (n=10).  Two types of anti-cariogenic orthodontic bonding materials, GAC’s NeoBond® Light Cure Adhesive and SeLECT Defense’s™ Light-Cure Orthodontic Adhesive, were compared against Transbond™ PLUS Color Change Adhesive by 3M. Victory Series mandibular first premolar brackets by 3M were bonded to all teeth which were mounted in epoxy resin. One half of each group was tested on an Instron 5566 universal debonding machine to assess the shear bond strength. The other half was debonded with the appropriate pliers and the tooth surface was examined at 3.5X magnification and scored according to the Adhesive Remnant Index (ARI).  Teeth  with  an ARI grade of  zero  were  examined  on  a  SEM to  determine  any  enamel  fracture.   

Result: No  statistically  significant  differences  in  bond  strength  among  the  bonding materials  were  found (F_2,27 = 1.69, p=0.203). The mean shear bond strength for GAC’s NeoBond® Light Cure Adhesive was 7.13±2.40 MPa. The mean shear bond strength for SeLECT Defense’s™ Light-Cure Orthodontic Adhesive was 5.28±2.08 MPa. The mean shear bond strength for Transbond™ PLUS Color Change Adhesive by 3M was 7.00±2.95 MPa. There was no significant difference in the three groups’ mean ARI (Kruskal-Wallis test = 0.86, p=0.650) with all samples except one testing either a 2 or 3. 

Conclusion: There were no statistically significant differences in the shear bond strength or the ARI among the three adhesives tested, and all exhibited clinically acceptable bond strengths.