Design and Development for the Customization of Orthodontic Mini-screw Surgical Guide under Biomechanical Consideration for Open Bite Patients
| Autor: | Yu-Tzu Wang, 王鈺詞 |
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| Rok vydání: | 2014 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 102 In recent years, mini-screw has been commonly used to achieve absolute anchorage during orthodontic treatment. However, when mini-screw is implanted in maxilla, there are many factors that can cause mini-screw unstable or damage surrounding structures. The purpose of this study is to develop the precision customization of orthodontic mini-screw surgical guide (under biomechanical consideration), and prove the performance by using the validated testing and clinical trial. First, the 3D digital geometry of the maxillary alveolar bone and tooth were reconstructed by using computed tomography images and reverse engineering, it could be applied to design surgical guide and implant mini-screw position. According to analysis result of the computer aided engineering (CAE), it can find not only the maximal Von-Mises strain, maximal principle strain and displacement of the interface between mini-screw and bone tissue, but also the displacement of the mini-screw head. Therefore, the ideal inserted path was performed according to the analysis results. After that, increasing guide hole and depth limiting device of the mini-screw and removable devices of the surgical guide by using computer aided design (CAD) on the surgical guide model. Final, surgical guide is made by 3D printing technology. In order to prove the indications of the surgical guide, it must be performed the functional test and clinical test. Results showed that, when the mini-screw inserted into palatal alveolar bone with 30 degree angle between the vertical (group A), the maximal Von-Mises strain around the bone tissue of the mini-screw was 1174μ. When the mini-screw inserted into palatal alveolar bone with horizontal direction (group B) the maximal Von-Mises strain around the bone tissue of the mini-screw was 694μ. Group B is greater than the A group but both were under critical strain level (4000μ). The ratio of group A to group B of the displacement between bone and mini-screw was found more than 3.2 times, and the mini-screw head displacement was found more than 100 times. Results showed that the group A is greater than group B. This study implied that the biomechanical response needs to be considered when using mini-screws as the skeletal anchorages. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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