The ornamental design for a hinge for oral sleepappliance, as shown and described.
2.1is a perspective view of hinge for oral sleep appliance;
2.2is a front view thereof;
2.3is a rear view thereof;
2.4is a top view thereof;
2.5is a bottom view thereof;
2.6is a right view thereof;
2.7is a left view thereof; and
2.8is an enlarged view of 2.6.
In the reproductions, the broken lines are for the purpose of illustrating portions of the hinge for oral sleep appliance and form no part of the claimed design.