Fractal Analysis of Ceramic FPDs

陶瓷 FPD 的分形分析

• 批准号: 8839510
• 负责人: JASON A GRIGGS
• 金额: $ 38.58万
• 依托单位: UNIVERSITY OF MISSISSIPPI MED CTR
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-03 至 2020-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8839510
• 关键词: Affect; Benchmarking; Ceramics; Clinical; Dental Porcelain; Dental crowns; Diagnosis; Dimensions; Elements; Environment; Failure; Fixed Partial Denture; Fractals; Fracture; Geometry; Glass; Goals; Industry; Literature; Location; Macor; Measures; Methods; Modeling; Nitrogen; Oral cavity; Orthopedic Surgery procedures; Patients; Phase; Plant Roots; Process; Property; Prosthesis; Prosthodontic specialty; Protocols documentation; Residual state; Scientist; Semiconductors; Silicon Dioxide; Specimen; Stress; Structure; Surface; Techniques; Technology; Testing; Time; Water; Work; Zirconium; improved; innovation; pressure; public health relevance; silicon nitride; tool; zirconium oxide

DESCRIPTION (provided by applicant): The fracture surfaces of ceramic prostheses can be characterized using fractal geometry to provide a wealth of information about the material properties and the conditions that were present at the time of failure. This potentially useful too is not widely employed because the current methods of fractal analysis are labor intensive, technique sensitive, and statistically biased. Our team has developed a new failure analysis method. It is an automated, unbiased method of rapidly and precisely measuring the fractal dimensional increment (D*) of fracture surfaces. The proposed project aims to validate this tool as an enabling technology to allow (1) determination of the failure origin in multilayered structures and (2) determination of material fracture toughness, both of which are useful in improving material processing. Furthermore, prior work leads us to hypothesize that both (1) and (2) can be determined from analyzing the D* of any fragment of a broken prosthesis - even when the failure origin has been lost or damaged. In addition, when the critical flaw is visible on the fracture surface, we should be able to estimate the stress at failure, which will be useful in diagnosing parafunction and/or the presence of an atypical residual stress. We will test the accuracy of this technique by comparing our results on two benchmark materials (silica glass and NIST standardized Si3N4) to the values in the literature for the same materials. We will test the utility of this technique by verifying our ability to detect which of three commercially availale dental ceramics is the failure origin in bilayered specimens (glass-ceramic veneered with porcelain, zirconia veneered with porcelain, and zirconia veneered with glass-ceramic). There are three overall goals of the proposed project: (1) Validate our innovative technique for use on monolithic and bilayered flexure beam specimens having a standard geometry with known failure stress levels. (2) Validate our innovative technique for use on all-ceramic fixed partial dentures (both crowns and three-unit FPDs). (3) Determine the effects of test conditions that deviate from the clinical case (monotonic vs. cyclic loading and wet vs. dry environment). The resulting information will have a high potential impact on the field of prosthodontics and may also be applicable to ceramic components used in orthopedic surgery and the automotive, aerospace, and semiconductor industries.

描述（由申请人提供）：可以使用分形几何形状来表征陶瓷假体的断裂表面，以提供有关材料特性和失败时存在的条件的大量信息。这种潜在有用的也不是广泛使用的，因为当前分形分析的方法是劳动密集型，技术敏感和统计学上的偏见。我们的团队开发了一种新的失败分析方法。它是一种快速和精确测量断裂表面的分形尺寸增量（D*）的自动化方法。拟议的项目旨在验证该工具作为一种使技术允许（1）确定多层结构中的故障来源，以及（2）确定材料断裂韧性，这两者都有助于改善材料处理。此外，先前的工作使我们假设（1）和（2）可以通过分析破裂的假体的任何碎片的d*来确定 - 即使失败的起源丢失或损坏。另外，当临界缺陷在 断裂表面，我们应该能够估计失败时的应力，这将在诊断副函数和/或存在非典型残留应力的情况下有用。我们将通过比较两种基准材料（二氧化硅玻璃和NIST标准化的SI3N4）与文献中相同材料的值进行比较，以测试该技术的准确性。我们将通过验证我们检测到三个商业上可用的牙齿陶瓷中哪个的能力来测试该技术的实用性，这是双层标本中的失败起源（玻璃陶瓷饰有瓷器，镀有瓷器，氧化锆饰有瓷器，带有瓷器，含有镀膜的氧化锆）。拟议项目的总体目标有三个：（1）验证我们的创新技术，用于用于整体和双层弯曲光束样品，具有具有已知故障应力水平的标准几何形状。 （2）验证我们的创新技术用于全陶瓷固定局部义齿（冠和三单元FPD）。 （3）确定偏离临床病例的测试条件的影响（单调与周期性负荷和湿环境与干燥环境）的影响。最终的信息将对肢体牙齿的领域产生很大的潜在影响，也可能适用于用于骨科手术和汽车，航空航天和半导体行业的陶瓷组件。