It appears that the 4 mm cuff of the pair abutment (Fig.10 >, 4.5x5.7(4) mm) is apical to the mesial crest (*).  The distal coronal implant threads seem to be covered by bone graft (Fig.11 <).  Therefore pair abutments with 5 mm or more cuff are required in cases of the uneven bone.   Implants have to be placed deep.

Implant Placed Deep Last Next Xin Wei, DDS, PhD, MS 1st edition 01/25/2017, last revision 12/12/2018