The diastema between the teeth #8 and 9 is probably due to mesial bone loss (Fig.2 *) and buccodistal displacement of the tooth #8.  To prevent peri-implantitis, the 1st thread (Fig.3 arrow) should be placed apical to the mesial crest (red dashed line) after socket treatment with 2% Xylocaine with 1:50,000 Epinephrine.

Place Implant Deep Last Next Xin Wei, DDS, PhD, MS 1st edition 02/20/2016, last revision 01/10/2019