The replacement of lost teeth with endosseous implants is aneffective and acceptable treatment modality. Oral implants play animportant role for replacing missing teeth to restore the function andaesthetics. The immediate placement of implants into fresh extractionsites has become a routine procedure. They have proven to be asuccessfully predictable treatment modality, and their osseointegrationoccurs with a high success rate.The aim of this study was to assess the effect of one stage surgeryin comparison with two stage surgery on osseointegration of immediatedental implants. Sixteen patients of both sexes indicated for extractionof posterior teeth and insertion of dental implants were included in thisstudy. They were divided into two equal groups.In group I, one -staged surgery, swiss plus dental implants wereinserted into the fresh extraction sockets, while group II two surgeryreceived eight implants of the tapered screw vent submerged andgrafted with fisiograft to fill the bony defects all around the fixtures ifneeded especially in molar teeth.The patients of both groups were evaluated both clinically andradio graphically at 1, 3, 6 and 12 months after loading. The clinicalparameters included the sulcus depth around the implant, mobility ofimplant and gingival index. The Bone density measurements around theimplants were carried out via direct radiography using Digora systemwhich were used to assess the bone density changes around the implantsat the different follow up periods and osseointegration.1-The results showed clinical success of all cases represented by decreaseof sulcus depth around implants , absence of implant mobility and goodgingival indices .2- The bone density measurements were higher in group II than that ofgroup I at 1,3 ,6 and 12 months after loading. Also, the change in bonedensity measurements from the first month to six months postoperativelyin group II (submerged) were higher than that of group I (nonsubmerged)but at end of the study there is no significant difference of the bonedensity values for both groups3- Bone healing around dental implant follow the normal sequences ofhealing in the form of progressive increase of the radiographic densityvalues all around the endosseous dental implant.