Dental

One of the following statements regarding pin retained restoration is NOT true

Pinholes should never be prepared at different levels on the tooth

A minimum of 0.5 mm clearance should be provided around the circumference of the pin for adequate condensation of the amalgam

Pinhole should located on a flat surface that is perpendicular to the proposed direction of the pinhole

The pinhole should be positioned no closer than 1 mm to DEJ and no closer than 1.5 mm to the external surface.