The Quad Helix provides continuous, controlled force for a variety of applications. It may be used for rotation or stabilization of molars, expansion or contraction of the arch, and even to assist in thumb, finger or tongue habit control. The principle advantage of the Quad Helix is that it allows for a differential amount of expansion in the anterior and posterior region of the arch. The appliance can either be soldered to the bands or attached via vertical or horizontal brackets. When it is soldered (as shown), all desired expansion must be adjusted into the appliance prior to cementation. If you choose the fixed/removable approach, adjustments can be made throughout treatment. Hint: Should you choose to use the soldered design, always request that the working model be returned with the appliance. The appliance can then be activated out of the mouth, seated back on the model, and tied with dental floss -- across the arch from lingual arm to lingual arm -- into a passive position. Once the appliance is fully seated and the cement has set, the dental floss can be cut and removed.