Yap A U, Mudambi S, Chew C L, Neo J C
Department of Restorative Dentistry, Faculty of Dentistry, National University of Singapore, 5 Lower Kent Ridge Road, Singapore 119074, Republic of Singapore.
Oper Dent. 2001 May-Jun;26(3):295-301.
This study investigates the mechanical properties (hardness, flexural strength and compressive strength) of a new light-cured resin-modified glass ionomer cement (Fuji II LC Improved). Effects of the increased powder:liquid ratio on mechanical properties and the correlation between different mechanical properties were also studied. Mechanical properties of the cement at manufacturer's recommended powder:liquid ratio (F), 2% (F2) and 4% (F4) increased powder weight were measured after one day, one week and one month storage in distilled water at 37 degrees C. Hardness testing (KHN; n = 5) was done with a digital microhardness tester (load = 500 g, dwell time = 15 seconds). Flexural and compressive strength testing (MPa; n = 5) were conducted based on ISO 4049 and BS6039, respectively. Results were analyzed using ANOVA/Scheffe's test (p < 0.05) and Pearson's correlation (p < 0.01). The maximum mechanical properties of Fuji II LC Improved were achieved at one week. The hardness, flexural and compressive strength at one week was significantly higher than at one day. A decrease in all mechanical properties was observed at one month. Mechanical properties were significantly affected by increased powder:liquid ratio. After one month storage, significance was as follows: Hardness--F, F2 > F4; Flexural strength--F4 > F, F2 and F > F2; Compressive strength--F, F2 > F4 and F2 > F. A significant very strong and negative correlation was observed between flexural and compressive strengths (r = 0.97).
本研究调查了一种新型光固化树脂改性玻璃离子水门汀（富士II LC改进型）的机械性能（硬度、弯曲强度和抗压强度）。还研究了粉液比增加对机械性能的影响以及不同机械性能之间的相关性。在37摄氏度的蒸馏水中储存一天、一周和一个月后，测量了制造商推荐粉液比（F）、粉重增加2%（F2）和4%（F4）时该水门汀的机械性能。使用数字显微硬度计（载荷 = 500 g，保压时间 = 15秒）进行硬度测试（努氏硬度；n = 5）。弯曲强度和抗压强度测试（MPa；n = 5）分别根据ISO 4049和BS6039进行。结果采用方差分析/谢费检验（p < 0.05）和皮尔逊相关性分析（p < 0.01）。富士II LC改进型的最大机械性能在一周时达到。一周时的硬度、弯曲强度和抗压强度显著高于一天时。在一个月时观察到所有机械性能均下降。机械性能受粉液比增加的显著影响。储存一个月后，显著性如下：硬度——F、F2 > F4；弯曲强度——F4 > F、F2且F > F2；抗压强度——F、F2 > F4且F2 > F。弯曲强度和抗压强度之间观察到显著的极强负相关性（r = 0.97）。
