Digital Porter Appliance for 3D printing, DLP, SLS, SLM and CNC millingThe W Arch or Porter appliance is fabricated using .036 wire. The appliance is activated by opening the apices and can be easily adjusted to provide more anterior or posterior expansion. The appliance should be manually opened 3-4 mm before insertion to provide proper forces. The expansion should continue at a rate of 2mm per month until the crossbite is overcorrected.Source:http://www.odlortho.com/produc... This digital orthodontic appliance was designed in 3Shape Appliance Designer and realistically rendered in KeyShot Pro 8.1