An orthodontic appliance that is particularly useful for correcting a class occlusion is disclosed. The appliance includes a mounting arrangement for mounting over an upper arch of a user having a front region and two arm regions extending rearward from the front region. The mounting arrangement includes an outer wall and an inner wall and a web extending there between. The outer wall, the web and the inner wall collectively define an upper channel within which the upper arch and teeth of a user are received to mount the appliance. They also define a lower channel for receiving the lower arch and teeth. The outer wall has an upper portion spaced forward of the upper arch teeth and gums forming an outer spacing formation for holding the buccal mucosa away therefrom. The appliance also includes a tongue elevator on a lower portion of the inner wall for raising position corresponding to an arch form will tend to return to the desired arch form. Further the resilient flexibility assists fitting of the appliance.