KU Leuven, Department of Materials Engineering, Kasteelpark Arenberg 44, B-3001 Leuven, Belgium`; KU Leuven, Department of Oral Health Sciences, BIOMAT - Biomaterials Research Group & UZ Leuven (University Hospitals Leuven), Dentistry, Kapucijnenvoer 7 block a, B-3000 Leuven, Belgium.
Periodontics and Ceramic Implantology (private Practice), 1401N Tustin Ave Suite #345, Santa Ana, CA 92705, USA.
Dent Mater. 2022 Oct;38(10):1633-1647. doi: 10.1016/j.dental.2022.08.004. Epub 2022 Sep 3.
Analyzing factors that may have led to fracture of zirconia implants by macro/micro-fractography.
Six one-piece and ten two-piece full-ceramic zirconia implants from two manufacturers, Z-Systems and CeraRoot, were retrieved after clinical failure. The time-to-failure ranged from 3 to 49 months. Optical and scanning electron microscopy (SEM) were used to analyze the fracture planes at the macro- and microscopic level. Treatment planning, surgical protocol, fracture-origin location and characteristic fracture features were assessed.
The fracture of all implants seemed to have been primarily due to overload in bending mode, while the fracture-initiation sites varied for the one- and two-piece implants. The fracture of all one-piece implants originated in the constriction region between two threads in the endosseous implant part. For two-piece implants, the abutment neck, internal abutment-implant connections and inner threads were found to be the main fracture-initiation sites. Surface defects at the root area for one-piece implants and damages at the abutment surface for two-piece implants were connected to the fracture origins. Importantly, the clinical failures of implants were often found to result from combined effects related to patient aspects, treatment planning/protocols, a high bending moment at the weakest link, implant-surface conditions and specific implant designs.
This study provided information to be considered for future optimization of treatment planning and the surgical protocol for zirconia implants. Optimization of the surface conditions and the zirconia-starting powder were also suggested.
通过宏观/微观断口学分析导致氧化锆种植体断裂的因素。
从两个制造商 Z-Systems 和 CeraRoot 中取出 6 个一体式和 10 个两件式全陶瓷氧化锆种植体，这些种植体在临床失败后被取出。失效时间从 3 到 49 个月不等。使用光学显微镜和扫描电子显微镜（SEM）来分析宏观和微观层面的断裂面。评估了治疗计划、手术方案、骨折起源位置和特征性骨折特征。
所有种植体的骨折似乎主要是由于弯曲模式下的过载引起的，而一体式和两件式种植体的骨折起始位置不同。所有一体式种植体的骨折都起源于骨内种植体部分两个螺纹之间的缩窄区域。对于两件式种植体，发现基台颈部、内部基台-种植体连接和内螺纹是主要的骨折起始部位。一体式种植体根部区域的表面缺陷和两件式种植体基台表面的损伤与骨折起源有关。重要的是，种植体的临床失败通常被发现是由于与患者方面、治疗计划/方案、最薄弱环节的高弯矩、种植体表面状况和特定种植体设计相关的综合因素造成的。
本研究提供了信息，可用于未来优化氧化锆种植体的治疗计划和手术方案。还建议优化表面条件和氧化锆起始粉末。
