This study was conducted to evaluate the difference between conventional acrylic and soft lined implant partial overdenture in mandibular Kennedy class I.Fourteen patients will be selected from the Outpatient's Clinic Prosthodontic Department, Faculty of Oral and dental Medicine of Cairo University.Selected patients will be divided into two equal groups.•For both the first and second groups: endosseous implant will be placed in the edentulous region.•Loading will be done after three to four month•In the first group conventional acrylic was used while in the second group the overdenture was lined with soft linerFor each patient, clinical as well as radiograghic evaluation has been done immediately after denture insertion and after 6 and9 month from prosthesis construction.Data obtained has been calculated tabulated and statistically analyzed. The results in this study showed that there was statistically significant difference between both groups in radiographic evaluation regarding bone height but not bone density. There was no significant difference regarding the gums around the implants or abutments