Date of Graduation
School of Dentistry
Background and Objectives: In today’s time, there is an increasingly crowded field of competition vying over a small subset of the population. Now, more than ever it is imperative to compete with efficiency and esthetics. Each step for orthodontic bonding procedures increases the chance for error to occur. However, orthodontic bracket, etchant, sealant, and adhesive material has the ability to improve bond strength and final outcome for the patient and provider. The aim of this study was to determine effective bonding protocols for Advanced Clarity APC™ Flash-Free Brackets and to determine if adhesive remains on enamel or orthodontic bracket after debond.
Experiment Design and Methods: A sample of 105 extracted human premolars were randomly divided to seven groups. Group 1 (control) stainless-steel APC™ II Adhesive Coated bracket bonded with phosphoric acid etch, Transbond™ MIP, Group 2 ceramic APC™ Flash-Free adhesive bracket with phosphoric acid etch and Transbond™ MIP, Group 3 ceramic APC™ Flash-Free adhesive bracket bonded with Transbond™ plus, Group 4 ceramic APC™ Flash-Free adhesive bracket bonded with phosphoric acid etch, Transbond™ plus, Group 5 ceramic APC™ Flash-Free adhesive bracket bonded with phosphoric acid etch, Assure Plus, Group 6 ceramic APC™ Flash-Free adhesive bracket bonded with phosphoric acid etch, Assure Plus, Pro Seal L.E.D., and Group 7 ceramic APC™ Flash-Free adhesive bracket bonded with Transbond™ Plus, Pro Seal L.E.D.. Orthodontic brackets were bonded to the facial surface of the premolar and placed in a thermocycler for 24 hours with baths of 5oC and 55oC. After 24 hours of thermocycling, the bracket was debonded with an Instron machine calculating shear bond strength (SBS). The bracket and tooth interface was looked under 10x magnification to determine the adhesive remnant index (ARI) and the nature of debond failure.
Results: To compare the difference in SBS and ARI scores between groups, we utilized one-way ANOVA followed by Tukey honestly significant difference (HSD) test. All statistical tests were two-sided and p-value of less than 0.05 was considered statistically significant. There was a significant difference in mean SBS between different groups (p-value
Conclusion: All groups except group 7 have clinically acceptable SBS to withstand occlusal forces during orthodontic treatment. APC™ Flash-Free adhesive has an inconsistent adhesive remnant index, however, there is a tendency for adhesive to remain on enamel after bracket debond.
Bernstein, Carl, "Effect of Shear Bond Strength with Novel APC™ Flash-Free Brackets and Different Bonding Protocol: An In Vitro Study" (2019). Graduate Theses, Dissertations, and Problem Reports. 3913.