University of São Paulo School of Dentistry, Department of Biomaterials and Oral Biology, Av. Prof. Lineu Prestes, 2227, São Paulo, SP 05508-000, Brazil.
University of São Paulo School of Dentistry, Department of Biomaterials and Oral Biology, Av. Prof. Lineu Prestes, 2227, São Paulo, SP 05508-000, Brazil.
Dent Mater. 2024 Jul;40(7):1047-1055. doi: 10.1016/j.dental.2024.05.008. Epub 2024 May 20.
To investigate the effect of hydrophilic/permeable polymer matrices on water sorption/solubility (WS/SL), Ca release, mechanical properties and hydrolytic degradation of composites containing dicalcium phosphate dihydrate (DCPD) particles.
Six composites were tested, all with 10 vol% of glass particles and either 30 vol% or 40 vol% DCPD. Composites containing 1BisGMA:1TEGDMA in mols (at both inorganic levels) were considered controls. Four materials were formulated where 0.25 or 0.5 of the BisGMA/TEGDMA was replaced by pyromellitic dianhydride glycerol dimethacrylate (PMGDM)/ polyethylene glycol dimethacrylate (PEGDMA). Composites were tested for degree of conversion (FTIR spectroscopy), WS/SL (ISO 4049) and Ca release (inductively coupled plasma optical emission spectroscopy). Fracture toughness (FT) and biaxial flexural strength/modulus (BFS/FM) were determined after 24 h and 60 days in water. The contributions of diffusional and relaxational mechanisms to Ca release kinetics were analyzed using the semi-empirical Salim-Peppas model. Data were analysed by ANOVA/Tukey test (alpha: 0.05).
WS/SL was higher for composites containing PMGDM/PEGDMA compared to the controls (p < 0.001). Only at 40% DCPD the 0.5 PMGDM/PEGDMA composite showed statistically higher Ca release than the control. Relaxation diffusion was the main release mechanism. Initial FT was not negatively affected by matrix composition. BFS (both DCPD fractions) and FM (30% DCPD) were lower for composites with hydrophilic/permeable networks (p < 0.01). After 60 days in water, composites with PMGDM/PEGDMA presented significant reductions in FT, while all composites had reductions in BFS/FM.
Increasing matrix hydrophilicity/permeability significantly increased Ca release only at a high DCPD fraction.
研究亲水性/可渗透聚合物基质对含二水磷酸氢钙（DCPD）颗粒的复合材料的水吸附/溶解度（WS/SL）、Ca 释放、力学性能和水解降解的影响。
测试了 6 种复合材料，均含有 10%体积的玻璃颗粒和 30%或 40%体积的 DCPD。含有 1BisGMA:1TEGDMA 的摩尔比（在两种无机水平下）的复合材料被认为是对照。有 4 种材料的配方中，BisGMA/TEGDMA 的 0.25 或 0.5 被均苯四甲酸二酐甘油二甲基丙烯酸酯（PMGDM）/聚乙二醇二甲基丙烯酸酯（PEGDMA）取代。通过傅里叶变换红外光谱法（FTIR 光谱法）、WS/SL（ISO 4049）和 Ca 释放（电感耦合等离子体发射光谱法）测试了复合材料的转化率。在水中 24 小时和 60 天后，测定了断裂韧性（FT）和双轴弯曲强度/模量（BFS/FM）。使用半经验 Salim-Peppas 模型分析 Ca 释放动力学中扩散和弛豫机制的贡献。数据通过方差分析/Tukey 检验（α：0.05）进行分析。
与对照相比，含有 PMGDM/PEGDMA 的复合材料的 WS/SL 更高（p<0.001）。仅在 40% DCPD 下，含有 0.5 PMGDM/PEGDMA 的复合材料的 Ca 释放明显高于对照。弛豫扩散是主要的释放机制。初始 FT 不受基质组成的负面影响。对于具有亲水性/可渗透网络的复合材料，BFS（两种 DCPD 分数）和 FM（30% DCPD）均较低（p<0.01）。在水中 60 天后，含有 PMGDM/PEGDMA 的复合材料的 FT 显著降低，而所有复合材料的 BFS/FM 均降低。
增加基质的亲水性/渗透性仅在高 DCPD 分数下显著增加 Ca 释放。
