Reuling N, Wisser W, Jung A, Denschlag H O
Department of Prosthodontic Dentistry, Dental School, University of Marburg, F.R.G.
J Biomed Mater Res. 1990 Aug;24(8):979-91. doi: 10.1002/jbm.820240802.
An experimental animal model was developed to investigate the release of metal ions from nonprecious dental alloys. Cast specimens of five Ni-Cr-alloys and Co-Cr-alloys were implanted intramuscularly in rabbits for periods of 2, 4, 8, and 12 weeks. The concentrations of nickel, chromium, cobalt, and molybdenum in the implant-loaded muscles were determined by electrothermal atomic absorption spectrometry (AAS) and neutron activation analysis (NAA). Reference muscle samples of each animal were analyzed to determine the individual control values. Significant increases in the tissue concentrations of these metals occurred in the immediate vicinity of the implants. Concentration gradients of the corrosion products were found between the implant contact tissue and the implant periphery (p less than 0.001). Tissue concentrations of nickel and chromium correlated (r less than 0.7). Microprobe analysis before and after implantation of the alloy specimens indicated an even corrosive loss of the alloy surfaces and changes in the surface element distributions. Advantages and limitations of this animal model are discussed, as well as its application in future studies.
建立了一种实验动物模型,以研究非贵金属牙科合金中金属离子的释放情况。将五种镍铬合金和钴铬合金的铸造标本肌肉内植入兔子体内,时长分别为2周、4周、8周和12周。通过电热原子吸收光谱法(AAS)和中子活化分析(NAA)测定植入合金的肌肉中镍、铬、钴和钼的浓度。分析每只动物的对照肌肉样本以确定个体对照值。在植入物紧邻区域,这些金属的组织浓度显著增加。在植入物接触组织与植入物周边之间发现了腐蚀产物的浓度梯度(p小于0.001)。镍和铬的组织浓度具有相关性(r小于0.7)。合金标本植入前后的微探针分析表明合金表面存在均匀的腐蚀损耗以及表面元素分布的变化。讨论了该动物模型的优点和局限性,以及其在未来研究中的应用。