List the causes of implant failure due to improper surgical technique and placement.

Failure due to surgical techniques and improper placement:

a) Off axis / severe angulation of implant.

b) Suboptimal primary stability.

c) Impaired healing and infection because of improper flap design.

d) Overheating the bone and exerting too much pressure.

e) Lesser space between implant and implant; and between implant and adjacent tooth.

f) Placing implant in immature grafted sites.

g) Placement of implant in an infected socket or a pathological lesion.

h) Contamination of implant body before insertion.