VERTICAL JAW RELATION The length of the face

VERTICAL JAW RELATION • The length of the face is determined by the amount of separation of the jaws

CLASSIFIED Vertical dimension at rest The length of the face when the mandible is in rest position Vertical dimension at Occlusion Is established by the natural teeth when they are present and in occlusion

PHYSIOLOGICAL REST POSITION The mandible is in the physiological rest position when all the muscles that close the jaws and all those muscles that open the jaw are in a state of minimum tonic contraction sufficient to maintain posture

VERTICAL DIMENSION AT OCCLUSION CAN BE RECORDED USING THE FOLLOWING METHODS Mechanical methods. 1. Ridge relation a) distance from the incisive papillae to mandibular incisors b)Parallelism of the ridges 2. Measurement of former denture 3. Pre extraction methods: -Profile photographs -Radiography -Articulated cast -Facial measurements

PHYSIOLOGICAL METHOD Physiological rest position ( niswongers ) Phonetics Esthetics Silverman closest speaking space Swallowing threshold

FREEWAY SPACE It is a space between the maxilla and the mandible when the mandible is in the physiological rest position

Increased vertical dimension Decreased vertical dimension Elongation of the face TMJ disturbances pain and clicking Ridge resorption Hypertrophy of the muscles TMJ disturbance Angular chelitis Senile Appearance