Objective: To compare between implant retained overdenture with two different attachments by measuring : Retention. Bone changes by radiographic evaluation. Subjects and Methods: Eight completely edentulous patients were selected from the Outpatient Clinic of the Prosthodontic Department; Faculty of Dental medicine, Al-Azhar University and classified into two equal groups. Each patient in two groups received two implants placed in the mandibular canine-premolar region bilaterally. Group (1): four patients received two implants using equator attachments. Group (2): four patients received two implants with using magnet attachments, and the study was randomized controlled trial with Calculated samples. Type of randomization in that study was Block randomization and The out comes was assessor blinded as the investigators didn't know the type of the attachment before measuring retention or amount bone resorption Results: Results revealed that, there was no statistically significant difference in bone loss between equator and magnet during the follow up period, and there were no statistically significant mean retention values in the two groups at base line and after 3 months. But 6 months; Magnet attachment showed statistically significantly lower mean retention values than Equator attachment. By time there was a statistically significant decrease in mean retention values of magnet rather than locator attachment. Conclusion: The use of equator and magnet attachments with two implant supported mandibular overdentures leads the same effect on crestal bone resorption. At the beginning the two attachment have the same retention quality by time magnet attachment loss some of its retention rather than locator attachment.