Similar to the Hilgers/Pendex appliance in both use and design, the Grumrax Appliance can develop an arch laterally and has the functional capacity to distalize and rotate the molars at the same time. There are, however, a few design modifications that make this appliance quite unique. The first design distinction is the use of an R.P.E. screw...and the obvious absence of any palatal acrylic. The second is the attachment of the distalizing springs to the body of the R.P.E. screw via horizontal sheaths. The distalizing springs are fully removable, making them easier to initially activate and reshape throughout treatment. They can also be unilaterally activated. This design is also more hygienic -- an excellent choice for patients exhibiting already-compromised dental hygiene. Other advantages provided by the "M" Pendulum Spring, can be viewed in the "M" Pendex Appliance section. Note: When an increase in arch length and width are both needed, many practitioners prefer to idealize the position of the molars at the same time that they expand the arch. Others prefer to initiate molar distalization several weeks (2 to 4) after transverse changes begin. Either way, once these movements are accomplished, the bicuspids and cuspid will have to be brought back in the arch form one at a time using fixed mechanics.