A mandibular advancement device (102,302) includes a first brace member (104,304) structured to engage an upper dentition of a user, a second brace member (106,306) structured to engage a lower dentition of a user, and a number of coupling assemblies (108,308) each coupling the first brace member to the second brace member. Each of the number of coupling assemblies includes an actuating element (114,314) structured to automatically adjust a dimension (136,336) of the coupling assembly. The actuating element is selected from the group consisting of a biasing element (114) and a volume responsive material (314).