Conclusion: Results demonstrated a small amount of marginal bone loss in both groups yet it was statistically significant, there was more marginal bone loss in group A (with xenograft ) than group B (with coral bone) but it was not statistically significant.

The aim of the study is to evaluate marginal bone loss using coral bone graft which is a xenograft of marine origin versus xenograft of bovine origin in immediate implant placement in maxillary esthetic zone as a gap filling material.
Materials and Methods: Ten patients were participated in this study (3 males and 7 females), with a mean age of 34 years having non restorable single or multiple maxillary anterior teeth (18 fresh extraction sockets were conducted in the study). patient's sockets were divided randomly and equally into 2 groups : Group A (control group): included 9 extraction sockets in 5 patients (one male and 4 females) which recived immediate post extraction implant placement with xenograft between the residual labial bone and implant surface. Group B (study group): included 9 extraction sockets in 5 patients(2 males and 3 females) which received immediate post extraction implant placement with coral bone between the residual labial bone and implant surface. Cone beam CT was taken immediately post operative and 4 months postoperatively to measure the amount of marginal bone loss in each group and then the percentage of bone loss in each group.