Without the latter (drill stopper), osteotomy depth control is still possible.  A 5x11.5 mm implant barely penetrates the sinus floor (Fig.4 (no postop nasal hemorrhage)).  The straight abutment is changed to an angled one (4.5 x15 degree A (5) mm) before impression retake (Fig.11,12 (<, dashed line: access hole)).  The implant should have been placed more mesial (Fig.13).

Uneven Bone Last Next Xin Wei, DDS, PhD, MS 1st edition 11/30/2017, last revision 07/31/2019