KU Leuven-BIOMAT, Department of Oral Health Sciences, KU Leuven (University of Leuven), Belgium.
J Dent. 2012 Apr;40(4):295-303. doi: 10.1016/j.jdent.2012.01.004. Epub 2012 Jan 16.
Polymerization shrinkage causes stress at the tooth-restoration interface. The magnitude of the stress depends upon several factors, such as the configuration factor (C-factor) of the cavity, the polymerization-conversion rate and filling technique. The aim of this study was to investigate the effect of curing time and filling method when high C-factor cavities were filled with low-shrinking composites.
Three low-shrinking (Filtek Silorane, 3M ESPE: FS; N'Durance, Septodont: N'D; Kalore, GC: Ka) and one conventional composite (Z100, 3M ESPE) were bonded into standardized occlusal Class-I cavities using either a two-step self-etch adhesive (Silorane System Adhesive, 3M ESPE: SSA) or a one-step self-etch adhesive (G-Bond, GC: GB). Five experimental groups were formed according to the employed adhesive/composite combination (SSA/FS, SSA/Z100, GB/N'D, GB/Ka, GB/Z100), and further divided into three subgroups conforming to curing time and filling technique (20 s/bulk; 80 s/bulk; 80 s/layered). For each subgroup, non-trimmed 1 mm×1 mm sticks were prepared from five teeth to measure the micro-tensile bond strength (μTBS) to cavity-bottom dentine.
The two-step self-etch adhesive SSA generated higher bond strengths than the one-step self-etch adhesive GB, irrespective of the filling method. When GB was used, bulk filling with a low-shrinking composite revealed the highest bond strengths. For all composites, the layering method provided the highest bond strengths.
The two-step self-etch adhesive Silorane System Adhesive (3M ESPE) performed better than the one-step self-etch adhesive G-Bond (GC), regardless of the composite used. When the latter all-in-one adhesive was used, effects of shrinkage stress became more apparent.
聚合收缩会在牙体修复界面产生应力。该应力的大小取决于多个因素，如窝洞的结构因子（C 因子）、聚合转化率和充填技术。本研究旨在探讨高 C 因子窝洞用低收缩复合材料充填时固化时间和充填方法的影响。
采用两步自酸蚀粘结剂（Silorane System Adhesive，3M ESPE：SSA）或一步自酸蚀粘结剂（G-Bond，GC：GB）将三种低收缩（Filtek Silorane，3M ESPE：FS；N'Durance，Septodont：N'D；Kalore，GC：Ka）和一种传统复合树脂（Z100，3M ESPE）黏结到标准化的窝沟Ⅰ类洞型中。根据所使用的粘结剂/复合树脂组合（SSA/FS、SSA/Z100、GB/N'D、GB/Ka、GB/Z100）将实验分为 5 组，再根据固化时间和充填技术进一步分为 3 个亚组（20 s/整块；80 s/整块；80 s/分层）。每组 5 个牙制备 1 mm×1 mm 的非修剪条，测量与窝洞底部牙本质的微拉伸粘结强度（μTBS）。
两步自酸蚀粘结剂 SSA 的粘结强度均高于一步自酸蚀粘结剂 GB，与充填方法无关。当使用 GB 时，低收缩复合材料的整块充填显示出最高的粘结强度。对于所有复合材料，分层法提供了最高的粘结强度。
两步自酸蚀粘结剂 Silorane System Adhesive（3M ESPE）的性能优于一步自酸蚀粘结剂 G-Bond（GC），与使用的复合树脂无关。当使用后者的全酸蚀粘结剂时，收缩应力的影响更加明显。
