An orthodontic trainer (1) for assisting the correction of the misalignment of teeth comprising a base member (2) made of nylon having a generally U-shaped form corresponding to the outline of the jaw of a user and a teeth engaging member (5) that encases the base member (2). The base member (2) has an open frame structure with curved inner and outer elongate frame members (10, 12) interconnected at spaced intervals by transverse frame members (15). The continuous teeth engaging member (5) that is made of silicone rubber or PVC comprises a web (40) and inner and outer flanges (44, 45) projecting up and down from both upper and lower faces of the web (40). These flanges (44, 45) and the web (40) define upper and lower channels within which the upper and lower teeth of the user can be received.
