Department of Prosthetic Dentistry and Dental Materials Sciences, Dental School and Clinics, Saarland University, Homburg, Saarland, Germany.
Clin Oral Investig. 2011 Apr;15(2):157-63. doi: 10.1007/s00784-009-0377-y. Epub 2010 Jan 19.
The aim of the study was to evaluate the influence of artificial aging on the fracture behavior of straight and angulated zirconia implant abutments (ZirDesign™; Astra Tech, Mölndal, Sweden) supporting anterior single crowns (SCs). Four different test groups (n = 8) representing anterior SCs were prepared. Groups 1 and 2 simulated a clinical situation with an ideal implant position (left central incisor) from a prosthetic point of view, which allows for the use of a straight, prefabricated zirconia abutment. Groups 3 and 4 simulated a situation with a compromised implant position, requiring an angulated (20°) abutment. OsseoSpeed™ implants (Astra Tech) 4.5 mm in diameter and 13 mm in length were used to support the abutments. The SCs (chromium cobalt alloy) were cemented with glass ionomer cement. Groups 2 and 4 were thermomechanically loaded (TCML = 1.2 × 10⁶; 10,000 × 5°/55°) and subjected to static loading until failure. Statistical analysis of force data at the fracture site was performed using nonparametric tests. All samples tested survived TCML. Artificial aging did not lead to a significant decrease in load-bearing capacity in either the groups with straight abutments or the groups with angulated abutments. The restorations that utilized angulated abutments exhibited higher fracture loads than the restorations with straight abutments (group 1, 280.25 ± 30.45 N; group 2, 268.88 ± 38.00 N; group 3, 355.00 ± 24.71 N; group 4, 320.71 ± 78.08 N). This difference in load-bearing performance between straight and angulated abutments was statistically significant (p = 0.000) only when no artificial aging was employed. The vast majority of the abutments fractured below the implant shoulder.
本研究旨在评估人工老化对直型和角度型氧化锆种植体基台（ZirDesign™；Astra Tech，Mölndal，瑞典）支撑前牙单冠（SCs）的断裂行为的影响。共制备了 4 个不同的实验组（n=8），代表前牙SCs。第 1 组和第 2 组从修复角度模拟了理想的种植体位置（左侧中切牙），允许使用直的预制氧化锆基台。第 3 组和第 4 组模拟了种植体位置受损的情况，需要使用角度型（20°）基台。使用直径为 4.5 毫米、长度为 13 毫米的 OsseoSpeed™种植体（Astra Tech）支撑基台。SCs（铬钴合金）用玻璃离子水门汀粘结。第 2 组和第 4 组进行热机械加载（TCML=1.2×10⁶；10,000×5°/55°）并在静态加载直至失效。使用非参数检验对断裂部位的力数据进行统计分析。所有测试样本均通过 TCML。在使用直基台的组或使用角度基台的组中，人工老化均未导致承载能力显著下降。使用角度基台的修复体的断裂载荷高于使用直基台的修复体（组 1，280.25±30.45 N；组 2，268.88±38.00 N；组 3，355.00±24.71 N；组 4，320.71±78.08 N）。只有在不进行人工老化的情况下，直基台和角度基台之间的这种承载性能差异才有统计学意义（p=0.000）。绝大多数基台在种植体肩部以下断裂。
