Fig.2 Cross section of 2nd molar to show design of implant placement (I) relative to the nerve (N).  Since bone height is relatively insufficient, we plan to use a short implant (6 mm in diameter, 5.7 mm in height).  In order for an implant to survive, there should be at least 1 mm of bone (pink line) on the either side of it.  According to manufacture's manual, the short implant should be placed 2-3 mm (green line) below the top of the bone.  After the short implant is placed, there is 4 mm of bone before touching the nerve (blue line).  We should be quite safe, back to original article