Kerosuo H, Moe G, Kleven E
Department of Dental Materials, University of Bergen.
Angle Orthod. 1995;65(2):111-6. doi: 10.1043/0003-3219(1995)065<0111:IVRONA>2.0.CO;2.
Five identical samples, each consisting of a fixed appliance, a headgear and a quad-helix for one-half of a dental arch, were immersed in 0.9% sodium chloride for 2 hours, 24 hours and 7 days. A control appliance was subjected to dynamic test conditions in a specially built "oral simulator" under similar test conditions. A significant release of nickel was detected from the quad-helix during the first two hours in static conditions, whereas during the following two periods significantly less nickel was released from the quad-helix than from the other appliances. The fixed appliance with simulated function showed a significantly higher cumulative release of nickel than the similar appliance in static conditions, 44.2 micrograms (SD 22.8) and 17.1 micrograms (SD 3.4). The total amounts of chromium released from the fixed appliance were significantly lower than those of nickel. No difference in the release of chromium was seen between the static and dynamic conditions. The results indicate certain differences in the amount and pattern of nickel release from different stainless steel orthodontic appliances in vitro. The release rate of nickel from dynamically loaded fixed appliances was found to be accelerated compared with that released under static conditions. Caution should be exercised when applying the results to the in vivo situation.
五个相同的样本，每个样本由一个固定矫治器、一个头帽和用于半侧牙弓的四螺旋扩弓器组成，将其浸泡在0.9%的氯化钠溶液中2小时、24小时和7天。一个对照矫治器在特制的“口腔模拟器”中于类似测试条件下进行动态测试。在静态条件下，最初两小时内从四螺旋扩弓器中检测到大量镍释放，而在随后两个时间段内，四螺旋扩弓器释放的镍明显少于其他矫治器。具有模拟功能的固定矫治器在静态条件下镍的累积释放量明显高于类似矫治器，分别为44.2微克（标准差22.8）和17.1微克（标准差3.4）。固定矫治器释放的铬总量明显低于镍。在静态和动态条件下，铬的释放没有差异。结果表明不同不锈钢正畸矫治器在体外镍释放量和模式存在一定差异。发现动态加载的固定矫治器镍的释放速率比静态条件下释放的速率加快。将这些结果应用于体内情况时应谨慎。
