Manuals_files/CD Manual 12.pdf - Removable Prosthodontics

Maxillo-mandibular Relationships - 29
Occlusal Vertical Dimension (OVD) is the distance between the maxilla and mandible
when the teeth or wax rims are in contact in centric position
PRP = ID + OVD
Technique
1. Use an indelible stick to make one dot on the philtrum, just below the columella of the
nose and another on the chin.
2. Measure the distance between the dots at physiologic rest position and also at the occlusal
vertical dimension. The patient should be sitting upright without head support - jaw
position is affected by posture.
3. The patient should open and close until lips barely touch - physiologic rest position.
Place a finger below the patient’s chin, then have patient close until wax rims touch - you
should feel movement of the mandible through the freeway space as a double check on
the measurements you made.
4. If insufficient interocclusal distance is present- remove wax from one or both of the rims
5. Use closest speaking space to confirm the occlusal vertical dimension- when speaking
sibilant sounds ("s", "z", sh", ch"), the rims should be at least 1 mm apart
6. Use large wax formers, #7 and Cottrel wax spatulas and wax, and red-handled knife
(scalpel) with Bunsen burner and torch to adjust rims.
7. Rims should make flat contact evenly along the entire length of the occlusal surface.
This is extremely critical. If the rims touch in one area first, the patient can be forced
into an eccentric or strained position.
8. If the patient does not contact evenly over the entire occlusal surface, scribe lines parallel
to the opposing occlusal surface on the facial sides of the maxillary and mandibular rims.
These guides should be used to parallel the rims during reduction.