Department of Prosthetic Dentistry, University Hospital, LMU Munich, Goethestraße 70, 80336, Munich, Germany.
Dental Team GmbH, Weißachener Str. 46, 83346, Bergen, Germany.
Clin Oral Investig. 2019 May;23(5):2331-2338. doi: 10.1007/s00784-018-2657-x. Epub 2018 Oct 6.
The purpose of the present study was to evaluate the retentive forces of CAD/CAM-fabricated polyetheretherketone (PEEK) secondary crowns on zirconia primary crowns over an artificial aging period representing 10 years of clinical service and compare them to electroformed secondary crowns made from pure gold.
Implant-supported zirconia primary crowns (N = 20) were CAD/CAM milled and provided either with electroformed secondary crowns (group ZE; N = 10) or CAD/CAM-fabricated PEEK secondary crowns (group ZP; N = 10). All secondary crowns were attached to a casted tertiary structure to ensure adequate stability. A universal testing machine was used to determine the retentive force values at baseline and after 1, 3, 5, and 10 years of simulated aging in the presence of artificial saliva. Data were analyzed applying Kolmogorov-Smirnov, Kruskal-Wallis, and Mann-Whitney U test. Level of significance was set at p < 0.05.
Retentive forces were not different for the groups ZE and ZP at baseline (median ZE 2.85 N; ZP 2.8 N; p ≤ 0.218). Because retentive force values changed significantly over simulation time for group ZE (Kruskal-Wallis; p ≤ 0.028), the values between the test groups ZE and ZP differed significantly (Mann-Whitney U) at 5 years (ZE 3.03 N; ZP 2.76 N; p ≤ 0.003) and 10 years (ZE 3.1 N; ZP 2.78 N; p ≤ 0.011).
PEEK secondary crowns exhibit stable retentive force values over 10 years of simulated aging showing no signs of deterioration while the retentive force values of electroformed secondary crowns increase over time.
PEEK might be a suitable alternative to proven metallic materials for the fabrication of secondary crowns.
本研究的目的是评估经过人工老化 10 年（相当于临床使用 10 年）后 CAD/CAM 制造的聚醚醚酮（PEEK）二次冠对氧化锆初级冠的固位力，并将其与纯金电铸的二次冠进行比较。
种植体支持的氧化锆初级冠（N=20）经 CAD/CAM 铣削后，分别用电铸的二次冠（ZE 组，N=10）或 CAD/CAM 制造的 PEEK 二次冠（ZP 组，N=10）进行处理。所有的二次冠都连接到铸造的三级结构上，以确保足够的稳定性。使用万能试验机在人工唾液存在的情况下，在基线时和 1、3、5 和 10 年模拟老化后测量固位力值。采用 Kolmogorov-Smirnov、Kruskal-Wallis 和 Mann-Whitney U 检验对数据进行分析。显著性水平设为 p<0.05。
ZE 组和 ZP 组在基线时的固位力没有差异（ZE 组中位数 2.85 N；ZP 组 2.8 N；p≤0.218）。由于 ZE 组的固位力值在模拟时间内显著变化（Kruskal-Wallis；p≤0.028），因此测试组 ZE 和 ZP 之间的值在 5 年（ZE 3.03 N；ZP 2.76 N；p≤0.003）和 10 年（ZE 3.1 N；ZP 2.78 N；p≤0.011）时差异显著（Mann-Whitney U）。
PEEK 二次冠在经过 10 年的模拟老化后表现出稳定的固位力值，没有恶化的迹象，而电铸的二次冠的固位力值随时间增加而增加。
PEEK 可能是制作二次冠的一种替代传统金属材料的合适选择。
