Fig.5 is a sagittal section of CT through the mesiobuccal and distobuccal roots of the tooth #2.  The CT was taken 2 years earlier when bone loss around the tooth #2 was not severe.  Arrow: mesial inclination of the tooth #2.

Even Sinus Lift

Xin Wei, DDS, PhD, MS 1st edition 01/11/2015, last revision 01/16/2015