Gerzina T M, Hume W R
Department of Restorative Dentistry, University of California, San Francisco 94143-0758.
J Dent Res. 1995 Jan;74(1):369-73. doi: 10.1177/00220345950740011301.
In previous work, the diffusion of monomers from composite and bonding resins through dentin was demonstrated in vitro. The monomers triethylene glycol dimethacrylate (TEGDMA) and 2-hydroxyethyl methacrylate (HEMA) were identified in samples from the pulp space. In the current study, we examined the effects of two levels of positive hydrostatic pressure on the passage of resin monomers through dentin in vitro from a composite-resin/bonding-resin combination to test the hypothesis that monomer diffusion is prevented by such pressure. An occlusal cavity prepared in the tooth crown was restored with the resins. Distilled water samples from the pulpal space were removed over time and analyzed for monomer content by high-performance liquid chromatography and mass spectrometry. Positive pulpal pressure reduced but did not prevent pulpward movement of diluent monomers that leach from bonding agents and from resin composites through dentin in vitro. The degree of reduction of diffusion was greater with TEGDMA than with the lower-molecular-weight monomer HEMA.
在之前的研究中，已在体外证实了复合树脂和粘结树脂中的单体通过牙本质的扩散。在牙髓腔样本中鉴定出了单体二甲基丙烯酸三乙二醇酯（TEGDMA）和甲基丙烯酸2-羟乙酯（HEMA）。在本研究中，我们检测了两种水平的正静水压力对树脂单体在体外从复合树脂/粘结树脂组合体通过牙本质的影响，以验证单体扩散会被这种压力阻止这一假设。在牙冠制备一个咬合面洞，并用树脂进行修复。随着时间的推移，从牙髓腔采集蒸馏水样本，并通过高效液相色谱法和质谱法分析单体含量。正牙髓压力减少了，但并未阻止稀释单体在体外从粘结剂和树脂复合材料中通过牙本质向牙髓方向的移动。与低分子量单体HEMA相比，TEGDMA的扩散减少程度更大。
