Determinants of the Durability of Resin-Dentin Bonds

树脂-牙本质粘结耐久性的决定因素

• 批准号: 6687957
• 负责人: DAVID H PASHLEY
• 金额: $ 39.09万
• 依托单位: AUGUSTA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-07-15 至 2007-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6687957
• 关键词: clinical research; collagen; composite resins; dental bonding material; dentin; extracellular matrix; human tissue; hydropathy; membrane permeability; monomer; solvents

DESCRIPTION: If resin composites are to provide a cost-effective alternative to silver fillings (dental amalgams), the adhesive bond between resins and dentin must be improved to increase its durability. To achieve adhesion of resins to dentin, the mineral phase is removed by acid etching. We posit that durable resin-dentin bonds require that stable resins fully replace the lost mineral volume. Such resin uptake requires extension of the collagen fibril matrix by water. Hydrophobic resins have been shown to be more stable when used as matrices for resin composites. Nevertheless, if hydrophobic monomers are applied to water-saturated dentin, they undergo phase changes and cannot penetrate the matrix. Hydrophilic monomers are more successful, but these bonds deteriorate over time by hydrolysis. Our recent work demonstrated that most of commercial adhesives cause a collapse of the water-saturated collagen matrix, that is largely due to their solvents having Hoy's solubility parameters for H-bonding forces (HHB) that are too low to prevent interpeptide H-bonding between collagen fibrils that occurs as the solvents replace water during monomer infiltration. We believe that the size of these interfibrillar spaces is critical because they serve both as diffusion channels for monomer infiltration and provide a protective resin coating for collagen fibrils. If the interfibrillar spaces collapse, there is little resin to protect the fibrils. We have ranked solvents and monomers for their HHB values. Ethanol has been shown to minimize matrix collapse, while acting as an excellent solvent for adhesive monomers. We have formulated a series of adhesive co-monomers that have a range of hydrophobicities/ hydrophilicities based on their HHB values, to test the hypothesis that hydrophobic resins provide more durable resin dentin bonds than current hydrophilic resins. The proposed studies provide a systematic sequence of experiments to select monomer/solvent combinations from a range of hydrophobic to hydrophilic resins, that minimize collapse of the matrix, maximize resin uptake between collagen fibrils, optimize resin dentin bond strength, while minimizing the permeability of resin-sealed dentin to water. We expect to minimize water sorption and maximize the long-term durability of resin-dentin bonds. This should provide important new insight into designing more durable resin-dentin bonds that can justify the placement of resin-based posterior composites.

产品说明：如果树脂复合材料是一种成本效益高的替代银填充物（牙科汞合金），树脂和牙本质之间的粘合剂结合必须得到改善，以增加其耐久性。为了实现树脂对牙本质的粘附，通过酸蚀刻去除矿物相。我们认为，持久的树脂-牙本质粘结需要稳定的树脂完全取代失去的矿物质体积。这种树脂吸收需要胶原纤维基质通过水的延伸。疏水性树脂已被证明在用作树脂复合材料的基质时更稳定。然而，如果将疏水性单体应用于水饱和的牙本质，则它们经历相变并且不能渗透基质。亲水性单体更成功，但这些键随着时间的推移因水解而劣化。我们最近的工作表明，大多数商业粘合剂导致水饱和的胶原基质的塌陷，这主要是由于它们的溶剂具有H-键合力（HHB）的Hoy溶解度参数，该溶解度参数太低而不能防止胶原原纤维之间的肽间H-键合，该键合发生在溶剂在单体渗透期间取代水时。我们认为，这些纤维间空间的大小是至关重要的，因为它们既作为单体渗透的扩散通道，又为胶原纤维提供保护性树脂涂层。如果纤维间空间塌陷，则几乎没有树脂来保护纤维。我们根据HHB值对溶剂和单体进行了排名。乙醇已被证明可以最大限度地减少基质塌陷，同时作为粘合剂单体的优良溶剂。我们已经配制了一系列粘合剂共聚单体，其具有基于其HHB值的一系列疏水性/亲水性，以测试疏水性树脂比当前亲水性树脂提供更持久的树脂牙本质粘结的假设。拟议的研究提供了一个系统的实验序列，以选择单体/溶剂组合从一系列的疏水性亲水性树脂，最大限度地减少基质的崩溃，最大限度地提高胶原纤维之间的树脂吸收，优化树脂牙本质粘结强度，同时最大限度地减少树脂密封的牙本质对水的渗透性。我们希望最大限度地减少吸水并最大限度地提高树脂-牙本质粘结的长期耐久性。这将为设计更持久的树脂-牙本质粘结提供重要的新见解，从而证明树脂基后牙复合材料的放置是合理的。