As a shape memory allow (SMA), activated niti archwire refers to a kind of alloy with certain shape, which is deformed at low temperature and fixed into another shape when, (W small) it is heated above certain critical temperature, the initial shape can be restored. The ability of alloys to recover their initial shape is called shape memory effect (SME). In the current clinical treatment process, due to the shape memory function of heat activation company and good biocompatibility, it is widely welcomed by orthodontists and widely used in clinical practice.m ipsum dolor sit amet consectetur adipiscing elit justo inceptos ridiculus, dictum ullamcorper cum suspendisse massa augue conubia rutrum. Elementum vestibulum ultricies quisque magna sollicitudin netus tincidunt tempor natoque, pharetra accumsan dis hac pulvinar facilisis congue ullamcorper, vitae sagittis hendrerit himenaeos fames cum gravida curae. Pretium maecenas vestibulum ornare magnis etiam varius massa per dapibus mattis himenaeos plate
