Objective: To evaluate and compare the effect of implant supported versus implant retained removable partial denture restoring Kennedy's class I cases on the supporting structures by measuring marginal bone loss and bone density around implant.
Subjects and Methods: Twelve patients were selected from the outpatient clinic, Prosthodontics Department, Faculty of Dentistry, Minia University. Both groups were classified into two equal groups; according to the implant superstructures either dome shaped abutment -and-ball and socket attachment. Each Patient of both groups had two implants in second molar position and received removable partial denture of the same design. Patients were followed up for one year radiographicaly regarding marginal bone loss and bone density around each implant. Group I: Six patients received RPD supported by dome shaped short abutments. Group II six patients received RPD retained by ball and socket attachments.
Results: Results revealed that there was Significant increase in marginal bone loss in group II implant retained with ball abutment than group I implant supported with dome shaped abutment and Significant increase in bone density in group I (implant supported) than group II (implant retained)
Conclusion: The use of dome shaped abutment produce less marginal bone loss and increase of bone density than the use of ball abutment.