Rest vertical dimension is the lower face height measured from chin point to nasospinale, with the mandible in rest position.

垂的概念可以是指下颌位于姿势位时这两个志点之的，主要与肌功能有关。

The length of the face determined by the distance of separation of jaws. The reference mark are nasospinale and chin point .The distance of these two marks is VD.

临床上，面下部垂的志点一般用鼻下点和颏下点，这两点分别位于口裂的上、下方。