Clinical Methods to Measure VDO and VDR
A practical guide for complete dentures, implant prosthodontics, and full-mouth rehabilitation.
VDO = Teeth in contact
Subnasale (nose point)
VDR = Jaw at rest
Freeway Space = VDR - VDO
Normal = 2 to 4 mm
Gnathion (chin point)
Definitions
VDO (Vertical Dimension of Occlusion) is the distance between two facial points when the teeth are in
contact. VDR (Vertical Dimension at Rest) is the distance between the same points when the
mandible is relaxed.
Willis Gauge Method
Mark the base of the nose and chin. Measure at rest for VDR and with teeth touching for VDO.
Physiologic Rest Position
Ask the patient to swallow, say 'mmm', and relax the jaw. Record the average of three
measurements.
Phonetic Method
Use 'S' sounds to assess closest speaking space and 'M' sounds to establish rest position.
Esthetic Method
Check lower facial height, lip support, tooth display, and profile.
Swallowing Method
Observe the position where the patient naturally closes after swallowing.
Pre-Extraction Records
Use old photographs, study casts, previous dentures, or cephalometric records.
Patient Comfort
Confirm speech clarity, absence of muscle fatigue, and comfortable lip closure.
Clinical Formula
VDO = VDR - 2 to 4 mm. Example: VDR 72 mm gives a VDO of 68 to 70 mm.
Recommended Workflow
Determine VDR, subtract 2-4 mm, verify with phonetics, esthetics, and comfort.
Common Errors
Excessive VDO can cause lip strain and clicking teeth. Reduced VDO can cause a collapsed facial
appearance.