Property of sintering zirconia ceramics that is important for metal-free bridge restoration

烧结氧化锆陶瓷的特性对于无金属牙桥修复很重要

• 批准号: 18592142
• 负责人: TAMAKI Yukimichi
• 金额: $ 2.41万
• 依托单位: Showa University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2006
• 资助国家: 日本
• 起止时间: 2006 至 2007
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-18592142/
• 关键词: zirconia; CAD; CAM; fit; metal-free restoration; mechanical property; 曲げ強さ; セラミックス; ブリッジ; 適合性

Zirconium oxide (Zirconia: ZrO_2) has been expected as a new ceramics material because metal-free restoration is available in dentistry. However, it is well-known that zirconia contracted with sintering process at the high temperature. Additionally, zirconia was too hard to form the complex design by cutting tool. The purpose of this study was to investigate the marginal and internal fit of CAD/CAM-fabricated zirconia frameworks. Furthermore, mechanical property was also investigated under the storage in the thermal stress with 20, 000 cycle. Single crown copings (A: abutment), three-unit bridge frameworks (APA, P: pontic), four-unit bridge frameworks (APPA), and five-unit bridge frameworks (A_1P_1A_2P_2A_3) were fabricated with raw-stage zirconia blanks using a commercial CAD/CAM system(KATANA[○!R], Noritake Dental Supply Co. Ltd., Aichi, Japan). Crown copings and frameworks were cemented to their respective master abutment models, and thickness of the cement layer was measured at specific measuring points. Marginal and internal fit of both APA and APPA were within clinical acceptance. However, the marginal gap and thickness of the cement layer on the axial surface of the pontic side of APA and APPA were slightly higher than those of the non-pontic side. As for the marginal gap of A_1P_1A_2P_2A_3 framework, it was superior to those of APA and APPA because the center abutment supported the framework to prevent distortion. Consequently, the axis of the abutment portion (A2) of the framework was kept vertical, thereby resulting in an excellent marginal fit for A2. Thus, findings of this study clearly showed that framework design was important to preventing distortion of long frameworks during post-machining sintering. On the other hand, the three point bending strength of zirconia bar after thermal cycling was less than that of bars stored in the atmosphere. Within this limited data, it was suspected that zirconia might be influenced by the storing environment.

氧化锆（Zirconia：ZrO_2）作为一种新型的陶瓷材料，在牙科中已成为无金属修复体的理想材料。然而，众所周知，氧化锆在高温下烧结过程中会收缩。此外，氧化锆太硬，无法通过切削工具形成复杂的设计。本研究的目的是研究CAD/CAM制造的氧化锆支架的边缘和内部适合性。此外，还研究了20，000次循环热应力储存条件下的力学性能。单冠内冠（A：使用商业CAD/CAM系统（KATANA[○！R]，Noritake Dental Supply Co. Ltd.，日本爱知县）。将冠帽和框架粘固到各自的主基台模型上，并在特定测量点测量粘固剂层的厚度。阿帕和APPA的边缘和内部拟合均在临床可接受范围内。但阿帕和APPA桥体侧轴面的边缘间隙和骨水泥层厚度略高于非桥体侧。A_1P_1A_2P_2A_3支架的边缘间隙比阿帕和APPA支架的边缘间隙小上级，这是因为中央基台支撑了支架，防止了支架的变形。因此，框架的邻接部分（A2）的轴线保持垂直，从而导致A2的极好的边缘配合。因此，这项研究的结果清楚地表明，框架设计是重要的，以防止变形的长框架在加工后烧结。另一方面，氧化锆棒在热循环后的三点弯曲强度小于在大气中储存的棒。在此有限的数据中，怀疑氧化锆可能受到储存环境的影响。

项目成果

Form Reproductivity and Conformity of Different Preparation Model Using Developed Digitizing Software

使用开发的数字化软件形成不同制备模型的再现性和一致性

• 发表时间: 2007
• 作者: Jun;KUNII;Yasuhiro;HOTTA;Yukimichi;TAMAKI;et. al;堀田 康弘
• 通讯作者: 堀田 康弘

CM/CAMを用いたセラミックブリッジ-各種ブリッジ形態による適合性-

使用 CM/CAM 的陶瓷牙桥 - 与各种牙桥形式的兼容性 -

• 发表时间: 2007
• 作者: Jun;KUNII;Yasuhiro;HOTTA;Atsushi;Ozawa;Akihirio;FYJISHIMA;Yukimichi;TAMAKI;et. al;国井 淳
• 通讯作者: 国井 淳

Effects of post-sintering on the axial surface fit of CAD/CAM fabricated zirconia frameworks

后烧结对 CAD/CAM 制造氧化锆框架轴向表面配合的影响

• 发表时间: 2007
• 作者: Jun;KUNII・Atsushi;OZAWA;et. al.
• 通讯作者: et. al.

CAD/CAMを用いたセラミックブリッジ

使用 CAD/CAM 的陶瓷桥

• 发表时间: 2007
• 作者: Jun;KUNII;Yasuhiro;HOTTA;Yukimichi;TAMAKI;et. al;堀田 康弘;国井 淳
• 通讯作者: 国井 淳

CAD/CAMを用いたセラミックブリッジ-ジルコニアコーピングの適合性

使用 CAD/CAM 的陶瓷桥-氧化锆内冠兼容性

• 发表时间: 2006
• 期刊: 歯科材料・器械 25巻・5号
• 作者: 国井 淳;堀田康弘;玉置幸道;嶋倉裕介;川和忠治;宮崎 隆
• 通讯作者: 宮崎 隆