正畸弓丝表面功能化修饰后抗腐蚀及抗菌性的研究

Corrosion resistance and antibacterial property of orthodontic arch wires after functionalized surface modification

目的表面修饰临床正畸不锈钢弓丝,比较修饰的不锈钢弓丝与未修饰的不锈钢弓丝的表面成分、表面形态、机械性能、抗腐蚀及抗菌性,为不锈钢弓丝的临床应用提供参考。方法选取不锈钢弓丝,尺寸为0.019英寸(0.48 mm)×0.025英寸(0.64 mm),以聚多巴胺为介质,共价接枝羧化壳聚糖修饰不锈钢弓丝。使用X射线能谱分析仪联合扫描电子显微镜分析表面成分,观察表面形态;使用显微硬度计测定微观硬度;使用CHI660C电化学工作站检测抗腐蚀性;采用WST试剂检测抗菌性。结果修饰的不锈钢弓丝表面含有C、N、O、Si、Cr、Mn、Fe元素,未修饰的不锈钢弓丝表面只含有Si、Cr、Mn、Fe元素;修饰和未修饰的不锈钢弓丝的微观硬度比较,差异无统计学意义;修饰的不锈钢弓丝比未修饰的不锈钢弓丝更具抗腐蚀性和抗菌性。结论通过聚多巴胺表面接枝羧化壳聚糖修饰正畸弓丝,机械性能没有明显改变,但能减轻弓丝腐蚀,抑制细菌生长,更利于正畸应用。

Objective To perform surface modification for clinical orthodontic stainless steel arch wires, compare surface components, surface patterns, mechanical properties, corrosion resistance, and antibacterial property between modified and unmodified stainless steel arch wires, and provide reference for the clinical application of stainless steel arch wires. Methods Stainless steel arch wires with the size of 0. 019 inch （0.48） × 0. 025 inch （0.64 mm） were used. Polydopamine was used as the medium and carboxymethyl chitosan （CMC） was covalently grafted on the surface of stainless steel arch wires. Surface components were analyzed and surface patterns were observed by energy dispersive X-ray analyzer and scanning electron microscope. Microhardness tester was used to test hardness of stainless steel arch wires. Electrochemical working station （CHI660C） was used to measure the corrosion resistance. WST reagent was used to detect the antibacterial property. Results The surface of modified stainless steel arch wires contained C, N, O, Si, Cr, Mn, and Fe, while the surface of unmodified stainless steel arch wires only contained Si, Cr, Mn, and Fe. The difference in microhardness between modified and unmodified stainless steel arch wires was not statistically significant. The corrosion resistance and antibacterial property of modified stainless steel arch wires were greater as compared withunmodified stainless steel arch wires. Conclusion The modification of orthodontic arch wires via polydopamine surface and grafted CMC can mitigate corrosion and inhibit the growth of bacteria without compromising the mechanical performance, so as to benefit the orthodontic application.