It appears that immediately after extraction (no Antibiotic) a long implant (15 or 16 mm, green outline) should be placed to bypass the bony defect with 2-point fixation (septum and sinus floor; Fig.4 (CBCT coronal section) red line).   A shorter implant, which is placed at the septum (4-5 mm tall), is not expected to be stable.

The diameter of the implant is to be determined after sequential osteotomy.  The minimal will be 4 mm (Fig.5 axial section) as long as the implant or osteotomy does not perforate the palatal (P) or buccal (B) socket substantially.

Bypass Defect

Xin Wei, DDS, PhD, MS 1st edition 02/11/2017, last revision 02/11/2017