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Can green tea be used to reverse compromised bond strength after bleaching?
Sandrine B Berger1, Renata P De Souza Carreira, Ricardo D Guiraldo
1Department of Restorative Dentistry, School of Dentistry, University of North Parana, Londrina, Brazil. berger.sandrine@gmail.com
European Journal of Oral Sciences
|July 12, 2013
Summary
Green tea extract can serve as an effective antioxidant for bleached enamel, improving microtensile bond strength before dental bonding procedures. This study found green tea comparable to sodium ascorbate in preserving bond strength after bleaching.
Area of Science:
- Dental Materials Science
- Biomaterials
- Nanotechnology
Background:
- Dental bleaching with carbamide peroxide can compromise enamel bond strength.
- Antioxidants are used to mitigate the adverse effects of bleaching on adhesion.
- Green tea possesses antioxidant properties that may benefit dental applications.
Purpose of the Study:
- To investigate the antioxidant effect of green tea on the microtensile bond strength (μTBS) of bleached enamel.
- To compare the efficacy of green tea with sodium ascorbate as an antioxidant treatment before bonding.
- To evaluate the impact of green tea on the adhesion of dental restorative materials to bleached enamel.
Main Methods:
- Human third molars were divided into six groups: control, bleaching only, bleaching + sodium ascorbate (SA), bleaching + green tea (GT), SA only, and GT only.
- Bleaching involved 10% carbamide peroxide application for 14 days.
- Antioxidant treatments (SA or GT gel) were applied for 1 hour before bonding with Adper Single Bond 2 and Filtek Z350 XT.
- Microtensile bond strength was tested using a universal testing machine, and fracture modes were analyzed via SEM.
Main Results:
- Bleached enamel (Group 2) showed significantly reduced μTBS (22.6 MPa) compared to the control (33.2 MPa).
- Green tea treatment (Group 4: 31.6 MPa; Group 6: 32.2 MPa) and sodium ascorbate treatment (Group 3: 30.0 MPa; Group 5: 29.1 MPa) significantly improved μTBS compared to bleaching alone.
- Green tea demonstrated comparable efficacy to sodium ascorbate in restoring bond strength to bleached enamel.
Conclusions:
- Green tea acts as an effective antioxidant for bleached enamel, preserving microtensile bond strength.
- Green tea can be considered a viable alternative antioxidant for dental bonding procedures on bleached enamel.
- The findings support the use of natural antioxidants like green tea in restorative dentistry to enhance adhesion.
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