The ridge at #31 is wide buccolingually, but uneven with buccal lower.  When a 3 mm drill reaches 13 mm in depth (Fig.1 (gingival level, flapless with Magic Split)), the patient feels pain with the osteotomy close to the Inferior Alveolar Canal (red dashed line).

Deep Placement of Short Implant Next

Xin Wei, DDS, PhD, MS 1st edition 12/11/2017, last revision 07/05/2018