Palatal (Fig.5 (coronal section) P) crest has bone loss (>), as compared to the buccal crest (<).  Sufficient bone graft is used for sinus lift and around the coronal end of the implant (Fig.6 *).  In fact the implant is placed in a trajectory to avoid use of angled abutment, as compared to design (Fig.5 on the right).虽然颊侧，腭侧骨壁少，

Sinus Lift Last Next  Xin Wei, DDS, PhD, MS 1st edition 01/24/2019, last revision 06/13/2021