Before revision: The NTI-TSS is a small transparent plastic device which is, in its most widely used form, worn over the two front teeth at night, and intended to prevent contact of the canines and molars.
After revision: The NTI-TSS is a small transparent plastic device which is, in its most widely used form, worn over the front four teeth, of either arch, at night, and intended to prevent contact of the canines and molars.