Curing models for photoactivated resin composites

描述（由申请人提供）：光活化复合材料用于许多生物材料应用，但最常见的是作为牙科修复材料。由于有限的光穿透和高聚合收缩率，这些修复体必须逐步建立，以确保足够的物理性能（即转换程度和硬度）和在牙齿界面的强附着力。我们假设一个固化模型可以预测光活化复合材料在现实牙科几何形状中的物理特性，并可以进行验证。这样的固化模型将需要(1)知道复合材料的光学特性，(2)预测复合材料中的光剂量（辐照度W时间），以及(3)将传递的光剂量与固化复合材料的物理特性联系起来。我们假设复合材料的光学性质在固化过程中发生变化，并且复合材料的物理性质可以使用80%固化的阈值光剂量来预测。我们期望一个经过验证的固化模型将提高对复合材料配方如何影响固化的理解，并提供有关复合材料-牙齿界面固化过程的关键信息。

DESCRIPTION (provided by applicant): Light-activated composite materials are used in many biomaterial applications, but most commonly as dental restoratives. Due to limited light penetration and high polymerization shrinkage, these restorations must be built up in increments to ensure both adequate physical properties (i.e., degree of conversion and hardness) and strong adhesion at the tooth interface. We hypothesize that a curing model that predicts the physical properties of light-activated composites in realistic dental geometries can be made and validated. Such a curing model would require (1) knowing the optical properties of the composite, (2) predicting the light dose (irradiance W time) in the composite, and (3) relating the delivered light dose to the cured composite's physical properties. We hypothesize that the composite's optical properties change during curing and that the composite's physical properties can be predicted using a threshold light dose for 80% curing. We expect that a validated curing model will improve understanding of how composite formulation affects curing and provide crucial information about the curing process at the composite-tooth interface. To test our hypotheses, we will produce experimental composites with known and varied ller types, sizes and compositions, monomer formulations, and with two different photosensitizers. Optical properties of cured and uncured composites will be measured and quantified as a function of light dose. The physical properties of composites cured at different irradiances and times will be measured and correlated with light dose to determine the 80% curing threshold. The optical property measurements and thresholds will be used in a dynamic Monte Carlo light transport model to predict physical properties. These predicted values will be validated by comparison with dental cavity preparations that have been restored with photo-cured composites.