Comparative study for the effect of two different types of attachment on supporting structures in implant retained mandibular complete overdenture

Objective: To compare between implant retained overdenture with two different attachments (Magnet and locator) by measuring the following: 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 with using locator attachments. Group (2): four patients received two implants with using magnet attachments.
Results: Results revealed that, there was no statistically significant difference in bone loss between locator 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 Locator attachment. By time there was a statistically significant decrease in mean retention values of magnet rather than locator attachment.
Conclusion: The use of locator and magnet attachments with two implant supported mandibular overdentures leads the same amount of bone resorption around the implants. At the beginning the two attachment have the same retention quality by time magnet attachment loss some of its retention rather than locator attachment due to poor corrosive resistance of magnets within oral fluid requires encapsulation within a new hybrid material.
Keywords: Dental Implants, Overdenture, Attachment, Retention