The Importance of the Freeway Space in ENT Evaluations of Airway Interferences

In the normal dental rest position, teeth are not in contact. The small vertical space between upper and lower teeth that normally occurs at rest is referred to as the dental freeway space, or interocclusal space. The normal freeway space measures 2-3mm at the molars, and 4-6mm at the incisors [1]. The most common causes of orofacial myofunctional disorders (OMDs) are airway interferences and allergies [2]. An OMD, whether the result of a digit habit or an altered oral posture such as a tongue protruding between the incisors, will hinge the mandible open, thus increasing the vertical rest position, or freeway space between the upper and lower jaws and teeth.