Department of Oral and Maxillofacial Surgery, University Medical Center Freiburg, Albert-Ludwigs-University of Freiburg, Hugstetter Str. 55, 79106, Freiburg im Breisgau, Germany.
Institute of Applied Materials, Applied Material Physics (IAM-AWP), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344, Eggenstein-Leopoldshafen, Germany.
J Mech Behav Biomed Mater. 2020 Jul;107:103759. doi: 10.1016/j.jmbbm.2020.103759. Epub 2020 Apr 3.
The interest in ceramic dental implants made of yttria-stabilized tetragonal zirconia polycrystals (Y-TZP) or alumina toughened zirconia (ATZ) has increased in recent years. However, in the light of aging, corrosion, and potential impurities of zirconia ceramics, the material composition of these implants and the associated term "metal-free" is persistently questioned. Thus, the present study aimed to conduct an elemental analysis of commercial zirconia dental implants to specify their elemental composition and to identify contaminants.
Nine commercial zirconia dental implant systems and corresponding material samples were analyzed using inductively coupled plasma-mass spectrometry (ICP-MS) and optical emission spectrometry (ICP-OES).
While the elemental composition was dominated by the main components Zr, Y and Al (in ATZ samples), all investigated samples contained impurities with Hf and contamination with alkali and alkali earth elements (Na, K, Mg, Ca), essential trace elements (e.g. Fe, Cu, Zn) but also potentially noxious metal elements (e.g. Ni, Cr). Furthermore, ultra-trace level contamination with the radionuclides U-238 and Th-232 was found in the majority of samples.
The results indicate that, although all the investigated Y-TZP and ATZ dental implants meet the currently relevant ISO standards and manufacturer's specifications, from an elemental point of view, they are not devoid of metals. Due to the lack of a universal definition and thresholds for the term "metal-free", the question of whether the examined zirconia dental implants can be holistically classified as "metal-free" or not remains a controversial, philosophical one.
近年来，对氧化钇稳定四方氧化锆多晶（Y-TZP）或氧化铝增韧氧化锆（ATZ）制成的陶瓷牙科种植体的兴趣日益增加。然而，鉴于氧化锆陶瓷的老化、腐蚀和潜在杂质问题，这些种植体的材料成分及其相关的“无金属”术语一直受到质疑。因此，本研究旨在对商业氧化锆牙科种植体进行元素分析，以确定其元素组成并识别污染物。
使用电感耦合等离子体质谱法（ICP-MS）和原子发射光谱法（ICP-OES）对 9 种商业氧化锆牙科种植体系统及其相应的材料样本进行分析。
尽管元素组成主要由 Zr、Y 和 Al（在 ATZ 样品中）组成，但所有研究样本均含有杂质 Hf，以及碱和碱土元素（Na、K、Mg、Ca）、必需微量元素（如 Fe、Cu、Zn）的污染，甚至可能还含有有害金属元素（如 Ni、Cr）。此外，在大多数样本中还发现了超痕量放射性核素 U-238 和 Th-232 的污染。
结果表明，尽管所有研究的 Y-TZP 和 ATZ 牙科植入物均符合当前相关的 ISO 标准和制造商规格，但从元素角度来看，它们并非不含金属。由于“无金属”术语缺乏通用定义和阈值，因此被检查的氧化锆牙科植入物是否可以被整体归类为“无金属”仍然是一个有争议的哲学问题。
