Functional cusp reduction

# The amount of functional cusp reduction required for metal-ceramic crown is -
a) 1.0 - 2.5 mm
b) 1.5 - 2.0 mm
c) 2.0 - 2.25 mm
d) 1.85 - 2.10 mm

The correct answer is B. 1.5 -2.0 mm. 

Metal ceramic restorations require a 1.5 - 2 mm reduction in the functional cusp and 1.0 - 1.5mm reduction in the non-functional cusp.