ANALYSIS OF POLYMERIZATION CONTRACTION IN COMPOSITES

复合材料聚合收缩分析

• 批准号: 3462313
• 负责人: RONALD L. SAKAGUCHI
• 金额: $ 9.93万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-08-01 至 1997-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3462313
• 关键词: biomaterial evaluation; biomechanics; composite resins; dental bonding material; dental occlusion; dental stress analysis; dentin; digital imaging; infrared spectrometry; oral facial restoration material; physical model; polymerization; robotics; scanning electron microscopy; tooth surface

There is mounting clinical and laboratory evidence that the flexure of the dental crown following intracoronal composite shrinkage may be related to a number of clinical and biological phenomena, including early dentin bond failure, crack initiation and propagation, and possibly post-operative symptoms. A major goal of this proposal is the determination of the extent and possible clinical significance of these effects in an in vitro experimental model with servohydraulic control and direct strain read out from intact and restored human teeth. The hypothesis to be tested is that polymerization contraction of composite restorative materials results in decreased longevity of the restoration due to internal stress development, early dentin bond failure, alterations in occlusal contacts, and crack initiation and propagation of the natural tooth structure. The biomechanics of composite polymerization kinetics and its effects on tooth structure will be investigated by: 1) strain gage characterization of polymerization contraction strain and stress, 2) evaluation of the deformation of the composite restored tooth through strain gage measurement, 3) evaluation of the response of the composite restored tooth during simulated occlusal loading in an artificial mouth and 4) validated finite element analysis of the restored tooth complex. It is hoped that these studies will increase the knowledge base of the biomechanical interactions internally, at significant boundaries and on the surface of the restored tooth complex. From this, new criteria in materials development can be determined and a sounder basis for materials choice, treatment planning, and fabrication of intracoronal restorations can be developed.

越来越多的临床和实验室证据表明， 冠内复合收缩后的牙冠可能是 与许多临床和生物学现象有关，包括早期 牙本质粘合破坏、裂纹萌生和扩展，并且可能 术后症状。 该提案的一个主要目标是 确定这些的程度和可能的临床意义 伺服液压控制的体外实验模型的效果 从完整和修复的人类牙齿中读出直接应变。 这 要检验的假设是复合材料的聚合收缩 修复材料会导致修复体寿命缩短 由于内应力的发展，早期牙本质粘结失效， 咬合接触的改变以及裂纹的萌生和扩展 天然牙齿结构。 复合材料的生物力学 聚合动力学及其对牙齿结构的影响将是 研究方式：1) 聚合反应的应变计表征 收缩应变和应力，2）评估变形 通过应变计测量复合材料修复牙齿，3）评估 复合修复牙在模拟咬合过程中的响应 加载到人工嘴中并 4) 验证有限元分析 修复后的牙齿复合体。 希望这些研究能够 增加内部生物力学相互作用的知识基础， 在重要的边界和修复牙齿的表面上 复杂的。 由此可以得出材料开发的新标准 为材料选择、治疗计划、 可以开发冠状修复体的制造。