In spite of difference in the sinus floor thickness at #15 between preop CBCT (~1 mm) and post #14 implant 2nd placement PA (~ 4 mm), Magic Lifter is tried with difficulty because of high bone density.  After a 4.8 mm short drill is used from 1 to 4 mm, sinus floor seems to be lifted gradually with the lifter.  Lifting is apparently complete after using the longer drill (4.8 mm) for ~ 6 mm and the lifter for ~7 mm.  Following placing 3 pieces of PRF membrane into the sinus, a 4x11 mm dummy implant for ~ 9 mm with <20 Ncm (Fig.1). 

The PA is taken with angulation.  *: buccal plate with exostosis; ^: lingual plate.

Sinus Floor Thickens after Neighboring Implant

Xin Wei, DDS, PhD, MS 1st edition 05/19/2017, last revision 05/19/2017