Department of Biomaterials Science, University of Turku, Turku, Finland.
J Adhes Dent. 2011 Aug;13(4):333-40. doi: 10.3290/j.jad.a19653.
Rigid rod polymers (RRPs) can be used as reinforcing fillers, comparable to inorganic particulate fillers, with the exception that RRP fillers can be dissolved from the surface, thus potentially improving their adhesion to polymer matrix. This study evaluated the effect of water storage on the microtensile bond strength (μTBs) of composite resin to dentin using experimental RRP modified primers.
Experimental primers were fabricated by dissolving RRP (Parmax, 1240, Mississippi PolymerTechnologies, USA) into dichloromethane (DCM) and mixing it with the monomers bis[2-(methacryloyloxy)- ethyl]phosphate (BMEP) and 3(methacryloyloxy)-propyltrimethoxysilane (MPS). Three experimental primers were prepared with different proportions for each dentin substrate. The same commercial etch-and-rinse adhesive was used with each group. Surfaces of human molars were wet ground occlusally. The experimental primers were applied onto dentin prior to light polymerization of the incremental composite resin buildup. Teeth were sectioned after 48 h, 6 months, or 12 months of water storage and then tested with the microtensile tester (Dillon Quantrol, Bisco).
ANOVA revealed that the solvent:monomer ratio and RRP had a significant effect (p < 0.05) on bond strength in 48-h groups (3-way ANOVA). Increasing the solvent:monomer ratio and addition of RRP into primers increased the μTBS values. However, long-term water storage decreased the μTBS values in the high solvent:monomer ratio group. In the other groups, water storage did not decrease the μTBS values.
One-year water storage lowered the dentin bond strength obtained using the primer with a high solvent:monomer ratio, whereas no decrease of bond strength was observed for the other study groups or for the control group.
刚性棒状聚合物 (RRP) 可用作增强型填料，与无机颗粒状填料相当，不同之处在于 RRP 填料可从表面溶解，从而有可能改善其与聚合物基质的粘结性。本研究使用实验性 RRP 改性底涂剂评估了水储存对复合树脂与牙本质之间微拉伸粘结强度 (μTBs) 的影响。
通过将 RRP（Parmax，1240，密西西比聚合物技术公司，美国）溶解在二氯甲烷 (DCM) 中并与单体双[2-(丙烯酰氧基)乙基]磷酸酯 (BMEP) 和 3-(丙烯酰氧基)丙基三甲氧基硅烷 (MPS) 混合，制备实验性底涂剂。为每种牙本质基底制备了具有不同比例的三种实验性底涂剂。每组均使用相同的商业酸蚀-冲洗型粘结剂。将人的磨牙颌面湿磨。在光聚合逐步复合树脂堆积之前，将实验性底涂剂施加到牙本质上。水储存 48 h、6 个月或 12 个月后，将牙齿切割成试件，然后用微拉伸试验机（Dillon Quantrol，Bisco）进行测试。
方差分析显示，溶剂：单体比和 RRP 对 48 h 组的粘结强度有显著影响（p < 0.05）（3 因素方差分析）。增加溶剂：单体比并向底涂剂中添加 RRP 会增加 μTBS 值。然而，长期水储存会降低高溶剂：单体比组的 μTBS 值。在其他组中，水储存并未降低 μTBS 值。
一年的水储存降低了使用高溶剂：单体比底涂剂获得的牙本质粘结强度，而其他研究组或对照组的粘结强度没有下降。
