Doi H, Takeda S
Department of Biomaterials, Osaka Dental University.
Shika Zairyo Kikai. 1990 May;9(3):375-86.
Dissolution of components from pure Ni, pure Ti, NiTi alloy and 316 L stainless steel was examined in Eagle's minimum essential medium to evaluate the effects of dynamic condition, pH, extraction period and filtration on the corrosion behaviour. Extraction medium was pH 3.5, 7.0 and 9.5. Extraction was done under static and gyrating conditions of 160 rpm, 200 rpm and 230 rpm for 3 and 7 days. Under static conditions, nickel was eluted from pure Ni and NiTi alloy at pH 3.5. Nickel and iron were slightly eluted from 316 L stainless steel at pH 3.5. However, dissolution of components from alloys was greater under dynamic conditions and with longer extraction periods. Dissolution of components, particularly of nickel at pH 3.5, was the highest from pure Ni, NiTi alloy and 316 L stainless steel. Following filtration with a 0.22 micron filter, the amount of metal decreased. Titanium was not detected in the filtrate under the conditions tested. The finding that a considerable amount of nickel was detected in the extract and filtrate indicated that the element was present in both a soluble and particulate form, especially at pH 3.5. The present results demonstrate that extraction under dynamic conditions is useful for investigating the degradation of metallic materials for medical and dental use.
在伊格尔氏最低限度基本培养基中检测了纯镍、纯钛、镍钛合金和316L不锈钢中各成分的溶出情况，以评估动态条件、pH值、提取时间和过滤对腐蚀行为的影响。提取介质的pH值分别为3.5、7.0和9.5。在静态以及160转/分钟、200转/分钟和230转/分钟的旋转条件下进行提取，提取时间为3天和7天。在静态条件下，pH值为3.5时，镍从纯镍和镍钛合金中溶出。pH值为3.5时，镍和铁从316L不锈钢中略有溶出。然而，在动态条件下以及提取时间更长时，合金中各成分的溶出量更大。各成分的溶出，尤其是pH值为3.5时镍的溶出，在纯镍、镍钛合金和316L不锈钢中最高。用0.22微米过滤器过滤后，金属量减少。在所测试的条件下，滤液中未检测到钛。在提取物和滤液中检测到大量镍这一发现表明，该元素以可溶和颗粒两种形式存在，尤其是在pH值为3.5时。目前的结果表明，动态条件下的提取有助于研究用于医疗和牙科的金属材料的降解情况。
