An advanced thermoplastic orthodontic retainer is disclosed. The prior art includes a clear piece of thermoplastic material of uniform thickness which is then heated to a soft state and adapted to a stone model of a patients teeth. The present invention incorporates a gradient of thickness of the plastic running from one end to the other. This gradient will exist in the final retainer, and it will take into account the normal pattern of opening and closing of the jaw during which the posterior segment is open less than the anterior segment when the teeth are close to contacting. The present invention retains the ease of fabrication, low cost, and aesthetics of the currently prescribed removable appliance while improving the durability and functionality. Dentists and orthodontists can use the present invention to prevent the unwanted side effects of the prior art including but not limited to posterior open-bites.
