固化模式对双重固化流动复合树脂聚合能力影响的研究

Influence of curing mode on polymerization of dual cured flowable resin composites

目的探讨光固化和化学固化模式对双重固化流动复合树脂聚合能力的影响。方法本研究于2011年12月至2012年3月在南京大学口腔医学院修复实验室完成。将双重固化流动复合树脂核材料A(Luxa Core)、B(Clearfil DC Core)和双重固化树脂水门汀C(DUOLINK)3种材料在光固化和化学固化2种固化模式下各制作5个试件,共制作30个试件。试件固化后0.5、24和120h,分别测量其表面努氏显微硬度以判断聚合度;固化后120h的试件用无水乙醇浸泡24h,再次测量其表面硬度,计算浸泡前后硬度降低百分比值以判断聚合的交联密度。采用单因素方差分析和独立样本t检验对数据进行统计学分析。结果 3种材料在2种固化模式下,硬度值均随测量时间的增加而增大(P<0.05),固化后120h硬度值达到最大;固化后120h的硬度值均是光固化模式的显著高于化学固化模式的[A材料:光固化模式(63.88±3.85)MPa,化学固化模式(39.26±0.89)MPa,P<0.05;B材料:光固化模式(66.94±0.97)MPa,化学固化模式(44.18±1.84)MPa,P<0.05;C材料:光固化模式(64.21±1.07)MPa,化学固化模式(50.69±1.47)MPa,P<0.05]。3种材料固化后120h的硬度值经无水乙醇浸泡24h后均出现显著降低(P<0.05),其中A和B材料在化学固化模式下的硬度降低百分比值显著大于光固化模式下的,而C材料在2种固化模式下的硬度降低百分比值差异无统计学意义[A材料:光固化模式(19.58±1.72)%,化学固化模式(25.18±2.82)%,P<0.05;B材料:光固化模式(17.74±1.75)%,化学固化模式(24.56±1.78)%,P<0.05;C材料:光固化模式(23.10±2.50)%,化学固化模式(23.72±1.65)%,P=0.658]。结论固化模式能够对双重固化流动复合树脂的聚合能力(聚合度和交联密度)产生显著影响。

Objective To investigate the influence of light and chemical curing mode on polymerization capability （de- gree of polymerization and cross-link density） of dual cured flowable resin composites. Methods The plexiglas circles （ inner diameter： 5mm, height：2mm ） were respectively injected and filled by dual cured flowable resin composite core build-up materials [ A （ Luxa Core ） , B （ Clearfil DC Core ） ] and dual cured resin cement [ C （ DUOLINK ） ], then specimens for chemical curing mode were stored untreated at 37℃ in the dark , while specimens for light curing mode were immediately light-irradiated for 20 seconds before storage. Surface hardness numbers were detected at 0.5,24 and 120 hours post-curing time to compare degree of polymerization indirectly .After that the specimens were soaked in 100% ethanol for 24 hours and percentage of reduction of hardness was recorded to compare cross-link density indirectly. Data were analyzed by One-way ANOVA and independent T test. Results For the 3 materials hardness of both curing mode increased with the post-cunng time t,r 〈 u.u3） and attained to the maximum values at 120 hours post-curing time. Hardness of light-curing mode at 120 hours post-curing time was greater than that of chemical-curing mode [material A： light-cured mode （61.27 ± 2.14） MPa, chemical-cured mode （39.26 ± 0.89） MPa,P 〈 0.05 ; material B： light-cured mode （66.94 ± 0.97） MPa, chemical-cured mode （ 44.18 ± 1.84） MPa, P 〈 0.05 ; material C ： light-cured mode （64.21 ± 1.07） MPa, chemical-cured mode （51.39 ± 1.22） MPa, P 〈 0.051. After soaking significant difference of percentage of reduction of hardness were detected between the 2 modes [material A： light-cured mode （19.58 ± 1.72）%, chemical-cured mode （25.18 ± 2.82）%, P 〈 0.05 ; material B： light-cured mode （17.74 ± 1.75）%, chemical-cured mode（24.56 ± 1.78）%, P 〈 0.05 ） ; material C ： light-cured mode （23.10 ± 2.50）%, chemical-cured mode（23.72 ± 1.65）%, P = 0.658]. Conclusion For dual cured flowable resin composites, curing mode exerts distinct influence on the degree of polymerization and cross-link density.