Curing models for photoactivated resin composites

描述(申请人提供)：光激活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剂。由于有限的光穿透性和较高的聚合收缩，这些修复体必须以增量的方式建立，以确保足够的物理性能(即转化率和硬度)和牙齿界面上的强大粘附力。我们假设，在现实的牙齿几何形状中，能够预测光激活复合材料的物理性质的固化模型可以被制作和验证。这样的固化模型将需要(1)知道复合材料的光学性质，(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性能联系起来。我们假设复合材料的光学性能在固化过程中发生变化，并且可以使用80%固化的阈值光剂量来预测复合材料的物理性能。我们期望，一个有效的固化模型将提高对复合材料配方如何影响固化的理解，并提供关于复合材料-牙齿界面处固化过程的关键信息。 为了验证我们的假设，我们将生产已知和不同类型、大小和组成、单体配方以及两种不同光敏剂的实验复合材料。固化和未固化复合材料的光学性能将作为光剂量的函数进行测量和量化。通过测量不同光强、不同时间固化后复合材料的物理性能，并与光剂量进行相关分析，确定80%固化阈值。光学性质测量和阈值将用于动态蒙特卡罗光传输模型，以预测物理性质。这些预测值将通过与使用光固化复合材料修复的牙洞准备进行比较来验证。

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.