What is “vertical dimension”?

Vertical dimension (VD) is the distance between the maxilla (upper jaw) and the mandible (lower jaw) when the teeth are closed together. In simple terms, it is the measurement of the face including the jaw.

The vertical dimension can be described as correct, reduced or excess:

Correct VD means that your teeth only come together when you eat or swallow. Try this simple test: Bring your lips lightly together. Now, relax as you usually would. Ideally, you should now have a small “freeway” space between your upper and lower teeth that measures about one to two millimetres. You will have this space whether you have dentures or your own natural teeth.

Reduced VD is seen when your teeth are excessively worn or when your dentures have been made incorporating an over-closed VD. Your jaw now has to move up farther than it normally would before your teeth come into contact. Your previously full lips will flatten out when you bite down and you will notice your face crunching up.

Persons who refuse to wear their upper and/or lower dentures will also notice that their jaws over close when they bite down. Reduced VD may result in more wrinkles in the mouth area, less biting force, and trauma to the TMJ (upper jaw joint). It can also contribute to hearing loss if allowed to persist for years.

Excess VD occurs when you have no freeway space and your teeth are in contact when your jaw is relaxed. This can cause a strain on your jaw’s muscles giving you an expressionless look, and increase the rate of shrinkage of your ridges.

NOTE:

Some injuries caused by an incorrect VD may be irreversible.