School of Dentistry, Federal University of Pelotas, Rua Gonçalves Chaves 457, Pelotas-RS, Brazil.
Dent Mater. 2013 Apr;29(4):413-8. doi: 10.1016/j.dental.2013.01.004. Epub 2013 Feb 9.
This study investigated the incorporation of calcium hydroxide (CH) and its effect on pH-neutralization and fundamental properties of model self-adhesive resin cements (SARCs).
Two-paste SARCs were obtained. Paste A: UDMA/Bis-GMA/TEGDMA/HEMA co-monomer, 25% phosphate monomer (GDMA-P), and 50% glass fillers; Paste B: UDMA/HEMA co-monomer, water, photoinitiators, and 60% glass fillers. CH was added at final concentrations of 0 (control), 0.25%, 0.5%, 1%, 2%, and 4%. Equal volumes of the pastes were mixed before testing. pH-neutralization of the eluate was followed during 24-h storage in distilled water. Other physico-chemical properties were evaluated only for the control and CH concentrations that neutralized the eluate. These evaluations included degree of CC conversion, film thickness, flexural strength/modulus, work-of-fracture, hardness, depth of cure, water sorption/solubility, and dentin bond strength. Statistical comparisons were conducted at a 5% significance level.
All CH concentrations above 0.25% caused pH increase of the eluate at 24h. The only CH concentrations leading to pH-neutralization were 2% and 4%. Compared with the control cement, the addition of 4% CH decreased the flexural strength, flexural modulus, work-of-fracture, CC conversion, and dentin bond strength. The cement with 2% CH had similar properties to the control cement, except for lower work-of-fracture and lower film thickness. Hardness, depth of cure, and water sorption were not affected by CH. The cement with 4% CH had lower solubility and film thickness than the other materials.
Incorporation of 2% CH to SARCs may lead to pH-neutralization without dramatically affecting other material properties.
本研究探讨了氢氧化钙（CH）的掺入及其对模型自粘接树脂水门汀（SARCs）的 pH 值中和及基本性能的影响。
获得了双糊剂 SARCs。糊剂 A：UDMA/Bis-GMA/TEGDMA/HEMA 共聚单体、25%磷酸盐单体（GDMA-P）和 50%玻璃填料；糊剂 B：UDMA/HEMA 共聚单体、水、光引发剂和 60%玻璃填料。CH 的终浓度分别为 0（对照）、0.25%、0.5%、1%、2%和 4%。测试前将糊剂等体积混合。在蒸馏水中储存 24 小时期间，跟踪洗脱液的 pH 值中和情况。仅对中和洗脱液的 CH 浓度和对照进行了其他理化性能评估。这些评估包括 CC 转化率、膜厚、弯曲强度/模量、断裂功、硬度、固化深度、吸水率/溶解度和牙本质粘结强度。在 5%的显著水平上进行了统计比较。
CH 浓度高于 0.25%的浓度均导致洗脱液在 24 小时时 pH 值升高。唯一能使 pH 值中和的 CH 浓度为 2%和 4%。与对照水门汀相比，添加 4%CH 降低了弯曲强度、弯曲模量、断裂功、CC 转化率和牙本质粘结强度。含 2%CH 的水门汀的性能与对照水门汀相似，只是断裂功和膜厚较低。硬度、固化深度和吸水率不受 CH 的影响。含 4%CH 的水门汀的溶解度和膜厚均低于其他材料。
将 2%CH 掺入 SARCs 可能会导致 pH 值中和，而不会显著影响其他材料性能。
