IRCT20200624047906N1 IRCT 2020-12-22 Tehran University of Medical Sciences Evaluation of the effect of LPRF on the stiffness and stability of implants placed in posterior maxilla Evaluation of the effect of LPRF on the stiffness of the implant – bone interfce and primary stability in implants placed in edentulous posterior maxilla 2020-11-21 anticipated 15 Complete https://irct.ir/trial/52023 interventional Randomization: Randomized, Blinding: Single blinded, Placebo: Not used, Assignment: Parallel, Purpose: Treatment, Randomization description: At the beginning of the surgery, the test and control group is determined for each patient by using sealed envelopes (draw a pocket), Blinding description: After surgery and suturing the area;The examiner clinician is asked to measure the ISQ of both the test and control sites and to obtain standard PA radiographs of both site and to determine the required values in them.It should be noted that after surgery, it is not possible to distinguish between the two groups, so the examiner is blinded to the study groups. 3 Implant placement in edentulous site. Intervention 1: Intervention group:Placement of LPRF membrane obtained from 20 cc of patient venous blood on the implant before placement in bone during surgery. Intervention 2: Control group: Implant placement in the bone in the usual way and without any additional intervention. Undecided - It is not yet known if there will be a plan to make this available Justification or reason for indecision in sharing IPD is There is no more data