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Adhesive Precoated Bracket: Is It Worth Using? Long-term Shear Bond Strength: An In Vitro Study.
Weerada Vorachart1, Nonglak Sombuntham1, Kulthida Parakonthun1
1Orthodontic Division, Department of Pedodontics and Preventive Dentistry, Faculty of Dentistry, Srinakharinwirot University, Bangkok, Thailand.
European Journal of Dentistry
|February 17, 2022
Summary
This study compared conventional metal brackets with adhesive precoated brackets, finding the latter had lower initial bond strength that increased over time. Thermal aging did not impact the failure pattern of either bracket type.
Area of Science:
- Orthodontics
- Dental Materials Science
Background:
- Conventional metal brackets rely on separate adhesives for bonding.
- Adhesive precoated brackets offer a potentially simplified chairside procedure.
Purpose of the Study:
- To compare the long-term shear bond strength (SBS) of conventional adhesive on metal brackets versus adhesive precoated brackets *in vitro*.
- To evaluate the adhesive remnant index (ARI) after debonding.
Main Methods:
- Ninety maxillary premolars were bonded with either Transbond PLUS Color Change Adhesive (TP) or Flash-Free adhesive precoated brackets (APC FF).
- Samples underwent different thermal cycling regimens before SBS and ARI measurements.
- Two-way ANOVA and Chi-square tests were used for statistical analysis.
Main Results:
- Adhesive precoated brackets (APC FF) exhibited significantly lower SBS than conventional adhesive (TP), except after 10,000 thermocycles.
- No significant differences in ARI were found between groups or subgroups.
- An ARI score of 1 was most common, indicating minimal adhesive remnants.
Conclusions:
- The shear bond strength of adhesive precoated brackets increases with time.
- Thermal aging does not influence the failure pattern of either bonding system.
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