After extraction of the residual roots at #12 and crown prep at #11, osteotomy at #12 is established with Pointed Lindamann bur and 2.2 mm bur for ~ 15 mm.  There feels to be sinus floor perforation; a parallel pin is inserted deeper than expected (Fig.1), but there is no membrane perforation.  Following sequential osteotomy, a 4x10 mm dummy implant is placed partially with stability (Fig.2).   The stability is partially due to the fact that the socket is smaller than the dummy implant.  The implant could be placed with no osteotomy.

Short, but Stable Implant Last Next Xin Wei, DDS, PhD, MS 1st edition 02/06/2018, last revision 10/17/2018