von Fraunhofer J A, Coffelt M T, Orbell G M
School of Dentistry, University of Louisville.
Angle Orthod. 1992 Winter;62(4):265-74. doi: 10.1043/0003-3219(1992)062<0265:TEOASA>2.0.CO;2.
The effect of artificial saliva and topical fluoride treatments on the force relaxation and change in force delivery by three brands of elastomeric chains over a 4 week period was studied. The effect of storage in air and in the different test media on the distraction to achieve forces of 150g and 300g was determined for the chains. The effect of the test media on load relaxation of the chains was also examined. Elastomeric chains exhibit good elastic behavior when distracted to an initial force of less than 300g. When forces exceeded 300g, permanent deformation occurred and the force delivery was less predictable. Exposure to artificial saliva and topical fluoride affected the elastic properties of the elastomeric chains and increased the distraction required to deliver both the 150g and 300g force. The increase in distraction for a force of 150g, however, was relatively small and probably insignificant in the clinical setting. The distraction required to produce 300g was significantly larger and appeared to be clinically significant. Pre-stretching the elastomeric chains by 100% of their initial length was not found to be advantageous in terms of the load relaxation behavior. There was less load relaxation found in chains that were immersed in distilled water and Acidulated Phosphate Fluoride than in chains exposed only to air.
研究了人工唾液和局部用氟化物处理对三种品牌弹性链在4周内的力松弛和力传递变化的影响。测定了弹性链在空气中和不同测试介质中储存对达到150g和300g力时的牵张的影响。还研究了测试介质对弹性链负荷松弛的影响。当弹性链被牵张至初始力小于300g时，表现出良好的弹性行为。当力超过300g时，会发生永久变形，力传递的可预测性降低。暴露于人工唾液和局部用氟化物会影响弹性链的弹性性能，并增加传递150g和300g力所需的牵张。然而，对于150g力而言，牵张的增加相对较小，在临床环境中可能无显著意义。产生300g力所需的牵张明显更大，似乎具有临床意义。就负荷松弛行为而言，将弹性链预拉伸至其初始长度的100%并无益处。与仅暴露于空气中的弹性链相比，浸入蒸馏水和酸性磷酸氟化物中的弹性链负荷松弛较少。
