Alqahtani Fawaz, AlAmar Mohammed
Department of Prosthodontics, College of Dentistry, Prince Sattam Bin Abdulaziz University, Al-Kharj, Saudi-Arabia.
Department of Prosthodontics, Ministry of Health, Riyadh, Saudi Arabia.
Eur J Dent. 2020 Feb;14(1):157-160. doi: 10.1055/s-0040-1702260. Epub 2020 Mar 13.
The objective was to assess modes of failures under static load (SL) among titanium (Ti) and one- and two-piece zirconia abutment (ZA) .
The Ti abutments were digitally scanned for the fabrication of the one- and two-piece zirconia abutment specimens. This was done to standardize the design of the one-piece abutment and make it the blueprint of the Ti abutment. Twenty-one implant abutments and 21 implant replicas were categorized into three groups as follows: group 1 (Titanium group), group 2 (one-piece ZA group), and group 3 (two-piece ZA group). A 250K-cycle, linear fatigue-load, reaching 10 to 210 Newton (N), was put on all specimens using an all-electric dynamic test instrument and the specimens were loaded until fracture.
Assessment of mode of fracture among the groups was done visually. Significance was based below 0.05.
Screw fracture ( = 7) and abutment bending at the apical part ( = 7) occurred in the Ti group. In the one-piece zirconia group, screw and abutment fractures occurred in seven and seven cases, respectively. In the two-piece zirconia group, screw fracture ( = 7) above the Ti zirconia junction (transgingival segment) and abutment fracture ( = 7) were determined as the failure modes.
In conclusion, all abutments underwent failures under SL ; and the mode of failure modes varied among the different abutment designs used.
评估钛（Ti）基台以及一体式和两件式氧化锆基台（ZA）在静态载荷（SL）下的失效模式。
对钛基台进行数字扫描，以制作一体式和两件式氧化锆基台标本。这样做是为了规范一体式基台的设计，并使其成为钛基台的蓝图。将21个种植体基台和21个种植体复制体分为以下三组：第1组（钛组）、第2组（一体式ZA组）和第3组（两件式ZA组）。使用全电动动态测试仪器对所有标本施加25万次循环、线性疲劳载荷，载荷范围为10至210牛顿（N），并对标本加载直至断裂。
通过肉眼评估各组之间的骨折模式。显著性基于0.05以下。
钛组发生螺钉骨折（=7）和基台根尖部弯曲（=7）。在一体式氧化锆组中，分别有7例发生螺钉和基台骨折。在两件式氧化锆组中，钛氧化锆交界处（龈上段）上方的螺钉骨折（=7）和基台骨折（=7）被确定为失效模式。
总之，所有基台在静态载荷下均发生失效；并且在所使用的不同基台设计中，失效模式各不相同。
