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Updated: Jun 8, 2026
14:53
Techniques for the Evolution of Robust Pentose-fermenting Yeast for Bioconversion of Lignocellulose to Ethanol
Published on: October 24, 2016
Ethanol wet-bonding challenges current anti-degradation strategy.
F T Sadek1, R R Braga, A Muench
1Department of Dental Materials, School of Dentistry, University of São Paulo, SP, Brazil.
Journal of Dental Research
|October 14, 2010
Summary
Chlorhexidine effectiveness in preventing hybrid layer degradation is compromised by water during dentin bonding. Biomimetic water replacement is key for long-term resin-dentin bond durability.
Area of Science:
- Dental Materials Science
- Biomaterials Engineering
- Adhesive Dentistry
Background:
- Chlorhexidine (CHX) is used as a matrix metalloproteinase (MMP) inhibitor to prevent hybrid layer degradation in dentin bonding.
- Incomplete water removal during wet-bonding procedures may compromise CHX's long-term effectiveness.
- The integrity of the hybrid layer is crucial for the longevity of resin-dentin bonds.
Purpose of the Study:
- To test the hypothesis that wet-bonding with water or ethanol does not affect chlorhexidine's efficacy in preventing hybrid layer degradation over 18 months.
- To evaluate the influence of water or ethanol wet-bonding on the stability of resin-dentin bonds pre-treated with chlorhexidine diacetate (CHD).
Main Methods:
- Acid-etched dentin was bonded using commercial adhesives under simulated pulpal pressure.
- Wet-bonding was performed with water or ethanol, with or without prior chlorhexidine diacetate (CHD) treatment.
- Bond strength and transmission electron microscopy (TEM) evaluations were conducted after 24 hours and after aging for 9 and 18 months in artificial saliva.
Main Results:
- Bonds created using ethanol wet-bonding on saturated dentin showed no degradation over time, preserving hybrid layer integrity.
- Bonds pre-treated with CHD and water wet-bonded showed preserved hybrid layer integrity at 9 months but severe degradation at 18 months.
- The null hypothesis was rejected, indicating that water presence significantly impacts CHX effectiveness.
Conclusions:
- The long-term effectiveness of chlorhexidine as an MMP inhibitor is compromised by water during dentin bonding.
- Biomimetic water replacement from collagen intrafibrillar spaces is proposed as a strategy to enhance the longevity of resin-dentin bonds.
- Optimizing water management during bonding is critical for durable adhesive restorations.
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