Background: There are different modalities of treatment for mandibular edentulous. This study aimed to evaluate marginal bone loss in implant retained mandibular overdenture using bullard versus ball and socket abutments clinically. Methods: twelve completely edentulous patients were selected from the Outpatient Clinic of the Prosthodontic department, Minia University, and were randomly allocated to two equal groups Ball & socket and Bullard abutments mandibular overdenture. All patients received 2 implants, 3.5 mm in diameter and 10 mm in length, were inserted in canine region. In the first group, prosthesis was retained by ball and socket attachments while in the second group, prosthesis was retained by Bullard attachment. For each patient in both groups marginal bone loss was assessed clinically by periodontal probe at time of denture delivery, then six and twelve months later. Results: The results showed marginal bone loss in both groups with significant increase in ball and socket group. Conclusions: Within the limitations of this study bullard abutments had advantages over ball & socket in terms of marginal bone loss among all follow up periods.