an upper arch adapted to receive at least some of the user's upper teeth, the upper arch having a midline that aligns substantially with the mesial plane of the user's mouth when the upper arch is inserted in the user's mouth;

a hook coupled to the upper arch proximate the midline of the upper arch, the hook comprising an end having an anterior surface adapted to be directed in an anatomically anterior direction when the upper arch is inserted in the user's mouth; and

a lower arch:

adapted to receive at least some of the user's lower teeth;

having a midline that aligns substantially with the mesial plane of the user's mouth when the lower arch is inserted in the user's mouth;

having a lingual surface adapted to be positioned lingual to the user's lower teeth when the lower arch is inserted in the user's mouth; and

comprising a recess in the lingual surface of the lower arch proximate the midline of the lower arch, the recess having a posterior surface adapted to be directed in an anatomically posterior direction when the lower arch is inserted in the user's mouth, the recess adapted to receive and position the end of the hook such that the anterior surface of the end of the hook contacts the posterior surface of the recess to pull the lower arch forward in the anatomically anterior direction to facilitate improved breathing.