An orthotic device (100) for retaining a patients mandible in an advancedor protrusive position comprises an intraoral anterior mandibular abutmentsurface (125) for resisting mandibular retraction by abutting the gingiva coveringthe mandible and an extramaxillary anterior maxillary abutment surface (115)against which the intraoral anterior mandibular abutment surface (125) is braced.In order to resist rotation of the dental orthotic produced by the interactionof the intraoral anterior mandibular abutment surface and the extramaxillaryanterior maxillary abutment surface, the orthotic device is provided with anintraoral posterior maxillary abutment surface (140). The relative positionsof the maxillary and/or mandibular abutment surfaces may be adjusted to suitthe requirements of the user.
