Effect of disinfection techniques on physical-mechanical properties of a microwave-activated acrylic resin

Abstract The effects of disinfection by microwave irradiation and immersion in peracetic acid on the physical-mechanical properties of a microwave-activated acrylic resin were evaluated. Specimens of acrylic resin were divided into a control group (specimens not disinfected) and 2 test groups subjected to one disinfection method: microwave irradiation at 850 W for 1 minute or immersion in 50 mL of 0.2% peracetic acid for 5 minutes. Specimens were submitted to Knoop hardness, flexural strength, flexural modulus, Izod impact, water sorption and solubility, glass transition temperature, and degree of conversion tests. Microwave disinfection significantly increased the mean Knoop hardness, Izod impact strength, water sorption, water solubility and glass transition temperature, whereas the flexural properties remained unaffected. Microwave disinfection increased the degree of conversion. Peracetic acid disinfection showed no changes in any properties. Both disinfection techniques did not adversely affect the evaluated properties.

摘要：本研究评估了微波照射与过氧乙酸（peracetic acid）浸泡两种消毒方式对微波激活型丙烯酸树脂（microwave-activated acrylic resin）物理力学性能的影响。将丙烯酸树脂试样分为对照组（未接受消毒处理的试样）与2个试验组，分别采用一种消毒方式处理：其一为850W微波照射1分钟，其二为于50mL 0.2%过氧乙酸溶液中浸泡5分钟。随后对所有试样开展努普硬度（Knoop hardness）、弯曲强度、弯曲模量、艾佐德冲击（Izod impact）、吸水率与溶解性、玻璃化转变温度（glass transition temperature）以及转化率（degree of conversion）测试。结果显示，微波消毒可显著提升试样的平均努普硬度、艾佐德冲击强度、吸水率、水溶性及玻璃化转变温度，弯曲性能未受影响；同时微波消毒可提高试样的转化率。过氧乙酸消毒对各项被测性能均无显著改变。两种消毒技术均未对所评估的性能产生不利影响。