Vertical dimension: a dynamic concept based on facial form and oropharyngeal function.

Craniofacial vertical dimension is a more accurate measure of facial proportion than mere measurement of the mid and lower part of the face. Craniomaxillary dimension is skeletally determined, whereas facial height of the lower part of the face is partly dependent on the vertical dimension of occlusion. Alterations in the vertical dimension of occlusion can dramatically affect the esthetics of the soft facial tissue. The "Golden Proportion" quantitatively defines ideal measured relationships and encourages a scientific appreciation of beauty. Faces with deficiencies in lower facial balance (brachyfacial) often exhibit insufficient height of the occlusal plane. The scientific literature has suggested a pliability of skeletal muscle allowing for physiologic variance in vertical facial height. Temporomandibular joint compliance is demonstrated with elevations in resting muscle length. Facial balance and location of the occlusal planes are the primary determinants for establishing an appropriate vertical dimension of occlusion.