Biomechanical analysis of anterior RBFPDs under static, dynamic and static-thermal coupled loadings

• Main Authors: Jian-Jia Chen, 陳建嘉
• Other Authors: Chun-Li Lin
• Format: Others
• Language: zh-TW
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/06093781929811155571

碩士 === 長庚大學 === 醫療機電工程研究所 === 92 === The geometric shape and mechanical structure of resin fixed partial denture, compared to traditional fixed partial denture, are relatively complex and unstable. The over low fixation intensity between the denture and abutment affects the denture/abutment interface system, and closely relates to the design of the denture, varied occlusion movements (static or dynamic), change of oral cavity temperature, and other biomechanics factors. This study used reverse engineering and computer-assisted technology to construct a computer 3D finite element model for resin fixed partial denture for upper incisor. After using astringent test to find the optimal grid partition, this study investigated the biomechanical problems resulted from varied structures of resin fixed partial denture (the length of the bridge), occlusion load direction (axial and lateral), and complicated mastication load inside the oral cavity (static, dynamic, thermal coupling). The analysis on static movement finds that longer bridge would lead to high stress to the dentures. Thus, the length of the bridge has significant effect on the overall intensity of the denture under static clenching load, and the effect of lateral load exceeds that of axial load. The thermal coupling analysis shows that temperature load at 15℃ is more likely to result in higher stress for the denture than at 45℃. In addition to masticatory force endured by the denture, when the temperature load increases, the overall stress increases significantly. The stress trend of the denture, due to thermal expansion factor, causes the stress corresponding to the bridge length opposite from the results of static analysis. In terms of the materials, full-porcelain denture shows lower stress under inferior thermal coupling lateral load than metal-porcelain denture. Thus, for clinical prosthesis, full-porcelain resin fixed partial denture is a sound choice for both aesthetics and strength purposes. The dynamic analysis shows that short application time results in higher stress to the denture. The length of the bridge is significant to the overall strength of denture under application time of 0.01sec. Thus, the clinical practice shall take into consideration of distance from the operation spot in order to choose appropriate treatment.