Interocclusal Distance
The vertical space between the occlusal surfaces of opposing teeth when the mandible is in the rest position, also termed the freeway space.
Full Definition
Interocclusal distance, commonly called freeway space, is the difference between the vertical dimension of rest and the vertical dimension of occlusion. It represents the gap between the upper and lower occlusal surfaces when the mandibular musculature is at physiological rest, typically 2–4 mm. This measurement is critical in prosthodontic planning, particularly for complete and partial denture construction, where loss of freeway space leads to muscular fatigue and discomfort. Editors must distinguish 'interocclusal distance' from 'vertical dimension of occlusion' (VDO), which refers to face height when the teeth are in contact.
Usage
Usage note: 'Freeway space' is widely used in British prosthodontic literature and is acceptable in semi-formal documents. 'Interocclusal distance' is preferred in formal academic writing.
In Context
- "The interocclusal distance was recorded as 3 mm, within the accepted physiological range." — Complete denture assessment clinic record
- "Inadequate freeway space following denture construction was identified as the cause of the patient's masticatory discomfort." — Prosthodontic case review