I have several patients that have about 5mm-7mm of native bone to the sinus and have poor health, poor healers and type 4 bone. I feel the lateral window may be tough due to healing and high disection. I am planning on doing a closed sinus lift and then come back a couple of months later and place the implant. In Summers intial papers he did future site osteotome lifts, but they seem to be out of favor since most people place the implant at the time of placement. Any opinions on me going back to this in this situation?