Khaled Mahmoud ELGaml ¹,Mostafa A. Elsyad ²,Ahmed Khalefa ^{3 1BDS,Faculty of Dentistry,Mansoura university 2Associate Professor of Removable Prosthodontics, Faculty of Dentistry, Mansoura University, Egypt . 3 lecturer of Removable Prosthodontics, Faculty of Dentistry, Mansoura University, Egypt}  Abstract: Aim: The aim of this study is to evaluate the patient bite force with three different attachments in the same patient used to stabilize mandibular two implant retained overdenture in patient with atrophied mandibular ridge. Materials and methods: 12 completely edentulous patients complaining from reduced stability and retention of their mandibular dentures. Received a new conventional maxillary and mandibular dentures (CD). After 3 months of adaptation, two implants were inserted at canines regions of the mandible. After 3 months of Osseo integration period, each patient received 3 prosthesis ; bar overdentures (BOD), telescopic overdentures (TOD), and locator overdentures (LOD). Maximum bite force recorded by using bite force transducer after 3 months after using each of the following prosthesis: CD, BOD, TOD and LOD. Results: There were a significant difference between implant retained overdenture and conventional complete denture, the force was nearly doubled with implant supported over denture. But there is no significant difference between attachments used although bar recorded higher levels of bite force. Males recorded higher forces than females Conclusion: implant retained overdenture recorded significant higher patient bite forces than complete denture regardless of attachment used. Bar attachment recorded higher forces