Department of Operative Dentistry, Cairo University, Cairo, Egypt.
Oper Dent. 2011 May-Jun;36(3):281-92. doi: 10.2341/10-105-L. Epub 2011 Jul 8.
This study evaluated the microtensile bond strength (μ-TBS) of low-shrinkage composites with their corresponding adhesive systems, Filtek Silorane/Silorane adhesive (SIL, 3M ESPE AG, Seefeld, Germany) and Aelite LS/One-Step Plus (AL, BISCO Inc, Schaumburg, IL, USA) in cavities with different C-factors. Filtek Z250/Adper Single Bond Plus (Z, 3M ESPE, St Paul, MN, USA) was used as a control.
Standardized Class I cavities were prepared in extracted human molars after removing occlusal enamel. Cavities were assigned into six different C-factors by applying nail polish to four walls, three walls, two walls adjacent to each other, two walls opposite to each other, one wall, or no walls. Resin composites with their corresponding adhesive systems were applied according to manufacturer instructions. Specimens were sectioned to obtain four rectangular beams from the center of the restorations and μ-TBS was measured. Data were analyzed by Weibull survival analysis. Shrinkage stresses of the resin composites were determined after 30 minutes from the start of light-curing using a tensometer testing machine. Flexure elastic modulus was determined using standard procedures, in accordance with ISO 4049. Data for shrinkage stress and elastic modulus were analyzed by one-way analysis of variance followed by a Tukey multiple-comparisons test (p<0.05).
μ-TBS of both SIL and AL were not affected by different C-factors; however, the bond strength of Z decreased significantly when the C-factor increased. Shrinkage stress results were 0.94 ± 0.1, 1.79 ± 0.18, and 2.14 ± 0.23 MPa for SIL, AL, and Z, respectively. The flexural modulus of both the SIL and the AL was significantly lower than that of Z.
Increasing C-factor did not negatively affect the bond strength of low-shrinkage composites.
本研究评估了不同 C 因素下角腔中低收缩复合材料与其相应粘接系统的微拉伸粘接强度（μ-TBS）。使用 Filtek Silorane/Silorane 粘接剂（SIL，3M ESPE AG，Seefeld，德国）和 Aelite LS/One-Step Plus（AL，BISCO Inc，Schaumburg，IL，美国）作为对照，使用 Filtek Z250/Adper Single Bond Plus（Z，3M ESPE，明尼苏达州圣保罗）。
从去除咬合釉质的人磨牙中制备标准化的 I 类腔。通过在四个壁、三个壁、两个相邻壁、两个相对壁、一个壁或无壁上涂指甲油，将腔分为六个不同的 C 因素。根据制造商的说明，应用树脂复合材料及其相应的粘接系统。从修复体的中心部位切取四个矩形梁，以获得标本，测量 μ-TBS。使用威布尔生存分析对数据进行分析。使用张力试验机在光固化开始后 30 分钟时测定树脂复合材料的收缩应力。按照 ISO 4049 的标准程序测定弯曲弹性模量。用单因素方差分析和 Tukey 多重比较检验（p<0.05）对收缩应力和弹性模量数据进行分析。
SIL 和 AL 的 μ-TBS 不受不同 C 因素的影响；然而，当 C 因素增加时，Z 的粘结强度显著降低。收缩应力结果分别为 SIL、AL 和 Z 的 0.94±0.1、1.79±0.18 和 2.14±0.23 MPa。SIL 和 AL 的弯曲弹性模量均显著低于 Z。
增加 C 因素不会对低收缩复合材料的粘结强度产生负面影响。
