An oral apparatus for mandibular jaw manipulation which in some embodiments may comprise: an upper tray configured to receive a plurality of maxillary teeth and a lower tray configured to receive a plurality of mandibular teeth. The upper tray may optionally have one or more upper anchor members configured as upper anchor members coupled to the upper tray. The lower tray may optionally have one or more lower anchor members configured as lower anchor members coupled to the lower tray. Each upper anchor member, which may be adjustable, may be configured to contact a lower anchor member, which may be adjustable, to adjust the positional relationship between the mandible and the maxilla of a mouth when a user wearing the oral apparatus closes their mouth to bring the upper and lower anchor members into contact with each other.
