The prognosis of a dental restoration is directly
determined by the amount of remaining tooth structure.
51 For generalized loss of vertical tooth height, the
clinician is faced with the dilemma of limited remaining
tooth structure that is necessary for adequate retention
and resistance of the restoration. The original tooth
height determines the active preparation height,
which can be defined as the vertical distance between
the preparation margin and the occlusal-axial line
angle. In order to avoid compromising the preparation
height, increasing the OVD should be considered to
provide adequate space to accommodate the restorative
material. The merit behind this technique is more
prominent in generalized loss of tooth height manifested
from tooth wear. As a result of this approach, the
teeth will be subjected to less pulpal trauma. In
addition, by utilizing the available vertical height of
the tooth, the indication for adjunctive crown lengthening
surgery is minimized.