Light-curable urushiol enhanced bisphenol A glycidyl dimethacrylate dentin bonding agent.

Objectives: The low durability of composite resin restorations can be attributed to the degradation of the resin dentin bonding interface. Owing to the presence of hydrophilic components in the adhesive, the integrity of the resin dentin bonding interface is easily compromised, which, in turn, leads to a reduction in bond strength. The hydrophilic nature of the adhesive leads to water sorption, phase separation, and leaching of the resin component. Therefore, hydrophobic adhesives could effectively be used to stabilize the integrity and durability of the resin dentin bonding interface.
Methods: We synthesized a novel hydrophobic dentin adhesive by partially replacing bisphenol A glycidyl dimethacrylate (Bis-GMA) with a light-curable urushiol monomer. The properties of the produced adhesive, including the degree of conversion, viscosity, contact angle, water sorption/solubility, and mechanical strength, were comprehensively examined and compared to those of the commercially adhesive Adper Single Bond ₂ as a positive control. The adhesive properties were determined using microtensile bond strength measurements, laser confocal microscopy, scanning electron microscopy observations, and nanoleakage tests. Finally, the novel adhesive was subjected to biocompatibility testing to determine its potential cytotoxicity.
Results: At a light-curable urushiol content of 20 %, the synthesized adhesive exhibited high degrees of conversion and hydrophobicity, low cytotoxicity, good mechanical properties, and outstanding adhesive strength.
Conclusions: The introduction of the light-curable urushiol into dentin adhesives can significantly enhance their hydrophobic, mechanical, and bonding properties, demonstrating potential to significantly improve restoration longevity.
Clinical Significance: The integration of light-curable urushiol has endowed the experimental adhesives with several enhanced functionalities. These notable benefits underscore the suitability of this monomer for expanded applications in clinical practice.
Competing Interests: Declaration of competing interest This manuscript has not been published or presented elsewhere in part or in entirety and is not under consideration by another journal. All study participants provided informed consent, and the study design was approved by the appropriate ethics review board. We have read and understood your journal's policies, and we believe that neither the manuscript nor the study violates any of these. There are no conflicts of interest to declare.
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