Department of Fixed Prosthodontics, Tokyo Dental College.
Tokyo Dental Junior College.
Bull Tokyo Dent Coll. 2021 Mar 13;62(1):15-26. doi: 10.2209/tdcpublication.2020-0028. Epub 2021 Feb 15.
A range of experimental designs have been used in destructive testing of composite resin CAD/CAM crowns. Various materials have been adopted for the abutment in such tests, including human or bovine dentin, stainless steel, PMMA, and composite resin, the selection of which is made in accordance with study objective or preference of the researcher. The purpose of this study was to determine how the material selected for the abutment material affected fracture load and maximum displacement. Destructive tests were conducted on composite resin crowns of the same design. Three types of material were used for the abutments together with 2 types of adhesive material. Images of each sample were acquired before destruction using a microfocus X-ray CT scanner to confirm the feasibility of a non-destructive test.The load required to fracture the composite CAD/CAM resin crowns depended on the abutment material used, with a decrease being observed in the order of composite resin, stainless steel, and PMMA. Maximum displacement decreased in the order of PMMA, composite resin, and stainless steel. Differences in the material used for setting (adhesive resin or polycarboxylate cement) showed no effect on fracture load. These results indicate that the load required to achieve destruction of resin CAD/CAM crowns varies according to the abutment material used.
一系列实验设计已被应用于复合树脂 CAD/CAM 冠的破坏性测试中。在这些测试中，各种材料被用于基台，包括人或牛牙本质、不锈钢、PMMA 和复合树脂，其选择是根据研究目的或研究人员的偏好进行的。本研究的目的是确定用于基台材料的材料选择如何影响断裂载荷和最大位移。对具有相同设计的复合树脂冠进行了破坏性测试。使用三种类型的材料作为基台，同时使用两种类型的粘合材料。使用微焦点 X 射线 CT 扫描仪在破坏前获取每个样本的图像，以确认非破坏性测试的可行性。使复合 CAD/CAM 树脂冠断裂所需的载荷取决于所用的基台材料，按复合树脂、不锈钢和 PMMA 的顺序依次减小。最大位移按 PMMA、复合树脂和不锈钢的顺序减小。用于设置（粘合树脂或聚羧酸酯水泥）的材料的差异对断裂载荷没有影响。这些结果表明，实现树脂 CAD/CAM 冠破坏所需的载荷根据所用的基台材料而有所不同。
