NBDHE. Review Questions: Quiz 192 March 18, 2016 by Hassan Shah The tooth preparation technique for a Class I amalgam on a mandibular first molar does not include which of the following? A. Maintaining a narrow isthmus width B. Initial punch cut placed in the most carious pit C. Establishment of pulpal depth of 1.5 to 2 mm D. Orientation of bur parallel to the long axis of the tooth Δ