Fixture mount does not fit at #13 as an anchor. After 3.5x7.3 mm drill with 10.5 mm offset at #14, sinus lift drills (3.6x18 and 19 mm) are used. The sinus floor is intact. A 9 mm offset should be used. Following 4.0x10 mm dummy implant is placed for ~ 8.5 mm, the sinus floor is perforated while the sinus membrane is intact. After water lift, PRF membrane and allograft are inserted and pushed upward with the 4.0x10 mm dummy implant for ~ 10 mm (Fig.1).
Xin Wei, DDS, PhD, MS 1st edition 08/13/2019, last revision 10/06/2019