A jaw exerciser for providing passive motion therapy such as that used totreat trismus is provided.The jaw exerciser has a user-adjustable distance between the upper jaw supportand the lowerjaw support. The jaw exerciser includes a shaft, a first or upper jaw supportframe including a firstjaw support, a second or lower jaw support frame including a second jawsupport, a distanceadjuster which may be in the form of a jack screw for manually adjusting thedistance betweenthe first jaw support and the second jaw support, and a retaining screw. Thejack screw may bereceived by the second or lower jaw support frame and engage the first orupper jaw supportframe. Removable bite pads may optionally be provided for installing on thefirst jaw support andthe second jaw support.
