Fig.2 (intraop photo) shows thread exposure.  The defect is a preexisting condition.  Bone graft may be not enough or get infected.  Or the implant is oversized, or placed too buccally (because of palatal defect).  In all, the implant is ~ 1 mm from the cortex.

Osteotape

Xin Wei, DDS, PhD, MS 1st edition 12/29/2014, last revision 02/14/2015