Department of Prosthodontics, Faculty of Dentistry, University of Niğde Ömer Halisdemir, Niğde, Turkey.
Department of Prosthodontics, Faculty of Dentistry, Ankara University, Ankara, Turkey.
J Esthet Restor Dent. 2022 Oct;34(7):1060-1067. doi: 10.1111/jerd.12944. Epub 2022 Jul 20.
Zirconia implants are assumed to satisfy the esthetic requirements that titanium implants cannot meet, however, there are not enough studies in the literature about narrow-diameter and angled zirconia implants that can be preferred especially in the anterior region. This in vitro study aimed to evaluate the fatigue resistance and fracture strength of narrow-diameter zirconia implants with angled abutments.
Forty-eight one-piece experimental zirconia implants and monolithic zirconia crowns were produced from 3-YTZP blanks. The implant diameters (3.0 or 3.7 mm) and the restoration types were determined according to three intraoral regions (upper central incisors, lower central incisors, and upper canine), and abutments were designed as straight or 15° angled. The samples were subjected to chewing simulation corresponding to 5 years of clinical performance and then the static loading test. The survival rates of groups were measured by the Kaplan-Meier log-rank test, and the fracture load values were estimated by using Kruskal-Wallis and Mann-Whitney U tests (p < 0.05).
All 3.0 mm diameter implants failed the fatigue test. The fatigue resistance of the implants with angled abutments was significantly lower than the straight abutments, and different crown designs were found to affect survival rates significantly. The fracture strengths of the surviving groups were above the maximum physiological chewing forces, and the differences were not significant.
The implant diameter, abutment angle, and restoration type have a significant effect on the fatigue behavior of zirconia implants.
The fracture strengths of the one-piece zirconia implants with a 3.7 mm diameter and a 15° abutment angle are above the chewing forces for the anterior intraoral region.
氧化锆种植体被认为能够满足钛种植体无法满足的美学要求，但文献中关于可优先用于前牙区的窄径和角度氧化锆种植体的研究还不够。本体外研究旨在评估带角度基台的窄径氧化锆种植体的疲劳强度和断裂强度。
从 3-YTZP 坯料中制作了 48 个一体式实验氧化锆种植体和整体氧化锆冠。根据三个口腔内区域（上中切牙、下中切牙和上尖牙）确定种植体直径（3.0 或 3.7mm）和修复类型，并设计直基台或 15°角度基台。样本经相当于 5 年临床性能的咀嚼模拟后进行静态加载试验。Kaplan-Meier 对数秩检验测量各组的存活率，Kruskal-Wallis 和 Mann-Whitney U 检验估计断裂载荷值（p<0.05）。
所有 3.0mm 直径种植体均未通过疲劳试验。带角度基台的种植体疲劳强度明显低于直基台，不同的冠设计对存活率有显著影响。存活组的断裂强度均高于最大生理咀嚼力，差异无统计学意义。
种植体直径、基台角度和修复类型对氧化锆种植体的疲劳行为有显著影响。
直径 3.7mm 和角度 15°基台的一体式氧化锆种植体的断裂强度高于前牙区的咀嚼力。
