To avoid drills or implant (particularly immediate one) touching the neighboring root, 2.2 mm drill will reach the depth (sequentially) first and take segmental panoramic X-ray.  Then return to the original sequence: diameter first and depth second to avoid bone necrosis.

Positional X-ray Last Next Xin Wei, DDS, PhD, MS 1st edition 05/19/2019, last revision 05/20/2019