Diolosà Marina, Donati Ivan, Turco Gianluca, Cadenaro Milena, Di Lenarda Roberto, Breschi Lorenzo, Paoletti Sergio
Department of Medical, Surgical, and Health Sciences, University of Trieste , Piazza dell'Ospitale 1, 34129 Trieste, Italy.
Biomacromolecules. 2014 Dec 8;15(12):4606-13. doi: 10.1021/bm5014124. Epub 2014 Nov 13.
This study aimed at investigating the effect of a methacrylate-modified chitosan on the durability of adhesive interfaces to improve the clinical performance of dental restorations. Chitosan was modified with methacrylic acid (Chit-MA70) on 16% of the amino groups. Viscosity, rheology, and (1)H NMR spectroscopy were performed to characterize the modified polysaccharide. Chit-MA70 was blended into a primer of an "etch-and-rinse" experimental adhesive system and tested on human teeth. The presence of methacrylate moieties and of residual positive charges on the polysaccharide chain allowed Chit-MA70 to covalently bind to the restorative material and electrostatically interact with demineralized dentin. The Chit-MA70 containing an adhesive system showed values of the immediate bond strength (26.0 ± 8.7 MPa) comparable to the control adhesive system (25.5 ± 8.7 MPa). However, it was shown that upon performing thermo-mechanical cycling treatment of the dental restoration on human teeth, the adhesive with the methacrylate-modified chitosan, in variance with the control adhesive, did not show any decrease in the bond strength (28.4 ± 8.8 MPa). The modified chitosan is proposed as a component of the "etch-and-rinse" adhesive system to efficiently improve the durability of dental restorations.
本研究旨在调查甲基丙烯酸酯改性壳聚糖对粘结界面耐久性的影响，以改善牙科修复体的临床性能。壳聚糖用甲基丙烯酸（Chit-MA70）对16%的氨基进行改性。通过粘度、流变学和¹H NMR光谱对改性多糖进行表征。将Chit-MA70混入一种“酸蚀冲洗”实验性粘结系统的底漆中，并在人牙上进行测试。多糖链上甲基丙烯酸酯部分和残余正电荷的存在使Chit-MA70能够与修复材料共价结合，并与脱矿牙本质发生静电相互作用。含Chit-MA70的粘结系统的即时粘结强度值（26.0±8.7 MPa）与对照粘结系统（25.5±8.7 MPa）相当。然而，结果表明，在对人牙上的牙科修复体进行热机械循环处理后，与对照粘结剂不同，含甲基丙烯酸酯改性壳聚糖的粘结剂的粘结强度没有任何下降（28.4±8.8 MPa）。改性壳聚糖被提议作为“酸蚀冲洗”粘结系统的一个组分，以有效提高牙科修复体的耐久性。
