The protective splint is a simple, inexpensive, vacuum formed appliance that can be used on either the maxillary or mandibular arch. Because it is vacuum formed, the occlusal facets are automatically duplicated in the appliance. Due to the thin nature of the material, a minimum bite opening of 1 to 2mm is possible. This is important for those patients who cannot tolerate a significant change in their vertical dimension. However, because it is thin, it will not hold up under excessive bruxing forces.