Abstract：
OBJECTIVE: To investigate the effect of hydrophilic/permeable polymer matrices on water sorption/solubility (WS/SL), Ca2+ release, mechanical properties and hydrolytic degradation of composites containing dicalcium phosphate dihydrate (DCPD) particles.
METHODS: 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 Ca2+ 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 Ca2+ release kinetics were analyzed using the semi-empirical Salim-Peppas model. Data were analysed by ANOVA/Tukey test (alpha: 0.05).
RESULTS: 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 Ca2+ 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.
CONCLUSIONS: Increasing matrix hydrophilicity/permeability significantly increased Ca2+ release only at a high DCPD fraction.
METHODS: 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 Ca2+ 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 Ca2+ release kinetics were analyzed using the semi-empirical Salim-Peppas model. Data were analysed by ANOVA/Tukey test (alpha: 0.05).
RESULTS: 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 Ca2+ 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.
CONCLUSIONS: Increasing matrix hydrophilicity/permeability significantly increased Ca2+ release only at a high DCPD fraction.
摘要：
目的：为了研究亲水性/渗透性聚合物基质对水吸附/溶解度（WS/SL）的影响，Ca2+释放，含有二水合磷酸二钙（DCPD）颗粒的复合材料的机械性能和水解降解。
方法：测试了六种复合材料，均具有10体积%的玻璃颗粒和30体积%或40体积%的DCPD。以摩尔形式（两种无机水平）含有1BisGMA：1TEGDMA的复合材料被视为对照。配制了四种材料，其中0.25或0.5的BisGMA/TEGDMA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）代替。测试复合材料的转化度（FTIR光谱），WS/SL(ISO4049)和Ca2+释放(电感耦合等离子体发射光谱)。在水中24小时和60天后测定断裂韧性（FT）和双轴弯曲强度/模量（BFS/FM）。使用半经验Salim-Peppas模型分析了扩散和松弛机制对Ca2释放动力学的贡献。通过ANOVA/Tukey检验(α:0.05)分析数据。
结果：含有PMGDM/PEGDMA的复合材料的WS/SL高于对照组（p<0.001）。仅在40%DCPD下,0.5PMGDM/PEGDMA复合物显示统计学上比对照更高的Ca2+释放。松弛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/可渗透网络的复合材料，BFS（两种DCPD级分）和FM（30％DCPD）较低（p<0.01）。在水中60天后，具有PMGDM/PEGDMA的复合材料的FT显着降低，而所有复合材料的BFS/FM均有所降低。
结论:增加基质亲水性/渗透性仅在高DCPD分数时显著增加Ca2+释放。
方法：测试了六种复合材料，均具有10体积%的玻璃颗粒和30体积%或40体积%的DCPD。以摩尔形式（两种无机水平）含有1BisGMA：1TEGDMA的复合材料被视为对照。配制了四种材料，其中0.25或0.5的BisGMA/TEGDMA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）代替。测试复合材料的转化度（FTIR光谱），WS/SL(ISO4049)和Ca2+释放(电感耦合等离子体发射光谱)。在水中24小时和60天后测定断裂韧性（FT）和双轴弯曲强度/模量（BFS/FM）。使用半经验Salim-Peppas模型分析了扩散和松弛机制对Ca2释放动力学的贡献。通过ANOVA/Tukey检验(α:0.05)分析数据。
结果：含有PMGDM/PEGDMA的复合材料的WS/SL高于对照组（p<0.001）。仅在40%DCPD下,0.5PMGDM/PEGDMA复合物显示统计学上比对照更高的Ca2+释放。松弛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/可渗透网络的复合材料，BFS（两种DCPD级分）和FM（30％DCPD）较低（p<0.01）。在水中60天后，具有PMGDM/PEGDMA的复合材料的FT显着降低，而所有复合材料的BFS/FM均有所降低。
结论:增加基质亲水性/渗透性仅在高DCPD分数时显著增加Ca2+释放。
