Alberto Laura H J, Kalluri Lohitha, Esquivel-Upshaw Josephine F, Duan Yuanyuan
Department of Biomedical Materials Science, University of Mississippi Medical Center, Jackson, MS 39216, USA.
Department of Restorative Dental Sciences, Division of Prosthodontics, University of Florida, Gainesville, FL 32611, USA.
Ceramics (Basel). 2022 Mar;5(1):34-43. doi: 10.3390/ceramics5010004. Epub 2022 Jan 5.
All-ceramic fixed dental prostheses (FDPs) tend to fracture at the connector regions due to high stress concentration at these areas influenced by their design. This study was performed as an adjunct to an existing clinical study to evaluate the influence of the different radii of curvature of gingival embrasure on the stress distribution of a three-unit all-ceramic implanted supported FDP. Three three-dimensional (3D) models were created by scanning two titanium dental implants, their suitable zirconia abutments, and a patient-retrieved dental prosthesis using a micro-CT scanner. The radius of curvature of the gingival embrasure for the distal connector of the FDP was altered to measure 0.25 mm, 0.50 mm, and 0.75 mm. A finite element analysis (FEA) software (ABAQUS) was used to evaluate the impact of different connector designs on the distribution of stresses. Maximum Principal Stress data was collected from the individual components (veneer, framework, and abutments). The radius of curvature of gingival embrasure had a significant influence on the stress distribution at the assessed components. The tensile peak stresses at all structures were highest in the 0.25 mm model, while the 0.50 mm and 0.75 mm models presented similar values and more uniform stress distribution.
全瓷固定义齿（FDPs）由于其设计导致连接区域应力集中，往往在这些区域发生断裂。本研究作为一项现有临床研究的补充，旨在评估龈缘不同曲率半径对三单位全瓷种植支持固定义齿应力分布的影响。通过使用微型CT扫描仪扫描两颗钛牙种植体、其合适的氧化锆基台以及一副患者取出的义齿，创建了三个三维（3D）模型。将FDP远端连接体的龈缘曲率半径改变为0.25毫米、0.50毫米和0.75毫米进行测量。使用有限元分析（FEA）软件（ABAQUS）评估不同连接体设计对应力分布的影响。从各个部件（饰面、支架和基台）收集最大主应力数据。龈缘曲率半径对评估部件的应力分布有显著影响。在0.25毫米模型中，所有结构的拉伸峰值应力最高，而0.50毫米和0.75毫米模型呈现出相似的值且应力分布更均匀。
