The present invention is a thermally formable plastic anatomical form for dentistry and a holder for the same. The holder is specially adapted to accommodate the plastic form in that it is heat resistant and features a bite guide to assure an even distribution of the plastic around the teeth of the patient and thickened occlusal surfaces to register specific tooth impressions more readily. The form according to the present invention may be used in any conventional dental work where a form may be needed, such as tray creation and stone molds, or may be utilized with therapeutic plastics so as to become a therapeutic dental device in and of itself.