Purpose: This clinical study presented the effectiveness of 2-stage posterior maxillary segmental osteotomy (PMSO) under local anesthesia in gaining interarch space to restore the posterior mandibular segment with dental implants. Materials and Methods: Nine patients who received two-stage PMSO for mandibular implant placement from 2003 to 2011 were included in the study. Of the 9 patients, 7 were female and 2 were male. Ages ranged form 28 to 72 (mean 46.6). Potential complications were investigated such as sinus infection, survival of bone segment, inflammatory root resorption of adjacent teeth, relapse of bone segment and timing of implant placement, delivery of implant prosthesis and stability of bone segment.Result: None of the patients showed relapse or complication. Bone segments were stabilized by opposed implant prosthesis. Conclusion Office-based 2-stage PMSO under local anesthesia can be considered a stable and predictable procedure. Also pedicle damage can be avoided by allowing favor of blood supply to the bone segments. From these advantages, it can be concluded that this surgical procedure can decrease post-operative complications.