NOVEL ADHESIVE CARIOSTATIC CEMENTS

新型粘性止龋水泥

• 批准号: 6238466
• 负责人: SABINE H DICKENS
• 金额: $ 13.56万
• 依托单位: AMERICAN DENTAL ASSOCIATION FOUNDATION
• 依托单位国家: 美国
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-09-29 至 1998-09-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6238466
• 关键词: biomaterial development /preparation; calcium phosphate; composite resins; dental adhesive /sealant; dental caries inhibitor; dentin; dogs; root canal therapy

The goals of the proposed research are to develop a pulp-capping material that can also serve as a base/lining cement, consisting of tetra- and dicalcium phosphates (TTCP and DCPA), hydroxyapatite (HAp) and carboxylated monomers/polymers. The cement combines the advantages of light-curing, pulp-capping and glass ionomer cements. The cement is termed "Synthetic Dentin" (SD) because it is composed of calcium phosphates and a polymer. The specific aims of the proposal are: (1) to formulate cements with sufficient pH levels of 8-10 and 10-12 and diametral tensile strength (DTS) of 16 MPa, (2) to make a two-paste system of SD with physical properties that do not decline more than 20% within 6 months of storage, (3) to develop SD with adhesiveness to dentin while maintaining ideal pH and high strength by adjusting the composition of resin, fillers, (4) to introduce anticariogenicity, (5) to evaluate SD in vivo, by studying the stimulation of dentin bridging over exposed pulps in animal teeth, (5) to evaluate a dentin substitute for instrumental and/or toxicity analyses. The experimental design intends to optimize pH and strengths, which will be measured for two resin systems and four concentrations of TTCP with the two Ca/P ratios of 1.96 and 2.05. The resin systems consist of pyromellitic glycerol dimethacrylate and two carboxylated and one carboxyl-free diluent resin. To facilitate the use of SD, a two-paste system will be tested by 24 h DTS after 1, 3, and 6 months of storage. Factors influencing the adhesiveness of SD to dentin are: (i) the type of resin, (ii) the presence of water in the liquid phase, (iii) the filler type and (iv) concentration, and (v) the presence of internal stresses in the cured cement. A 2/5-1 fractional factorial design will be used to evaluate the effect of factors i-v on pH, DTS and the shear bond strength. Two selected formulations of SD will be tested in vivo on exposed pulps in dogs (7 teeth per formulation). Reproducibility of material properties of the dentin substitute will be assessed by permeability, XPS and IR spectroscopy.

本研究的目的是开发一种盖髓材料 也可以作为基础/衬里水泥，由四和 磷酸二钙（TTCP和DCPA）、羟基磷灰石（HAp）和 羧化单体/聚合物。 水泥结合了以下优点： 光固化、盖髓和玻璃离子水门汀。 水泥是 称为“合成牙本质”（SD），因为它是由钙 磷酸盐和聚合物。 该提案的具体目标是：（1）配制水泥， 8-10和10-12的足够pH水平和径向拉伸强度 (DTS)（2）制备了SD与物理 性能在储存6个月内下降不超过20%， (3)在保持理想pH值的情况下， 通过调整树脂、填料、（4） 引入抗龋性，（5）通过研究 刺激动物牙齿中暴露牙髓上的牙本质桥接，（5） 评价牙本质替代品的工具性和/或毒性 分析。 实验设计旨在优化pH值和强度， 测量两种树脂系统和四种浓度的TTCP， Ca/P比值分别为1.96和2.05。 树脂体系由以下组成： 均苯四酸甘油二甲基丙烯酸酯和两个羧基化和一个 不含羧基的稀释树脂。 为了方便SD的使用， 系统将在储存1、3和6个月后进行24小时恒温检测。 影响SD对牙本质附着力的因素有：（1）SD的类型 （ii）在液相中存在水，（iii）在液相中存在水。 填料类型和（iv）浓度，以及（v）内部 固化水泥中的应力。 2/5-1部分析因设计将 可用于评价因子i-v对pH、pH值和剪切力的影响 粘结强度 将对两种选定的SD制剂进行体内试验 在狗的暴露牙髓上（每种制剂7颗牙齿）。 重现性 牙本质替代物的材料特性将通过 渗透性、XPS和IR光谱。