To report the complications experienced and the outcomes of simultaneous or staged dental implants placed during 101 consecutive sinus augmentation procedures through the lateral window approach.Sixty-eight consecutive patients underwent a total of 101 sinus augmentations. Thirty-nine patients were operated on unilaterally and 29 bilaterally. A total of 141 implants were installed, 65 simultaneously and 76 in a second stage.In 13 of the 101 sinuses, the Schneiderian membrane was perforated. Three patients developed maxillary sinusitis. Two patients suffered perioperative hemorrhages. One patient had a wound dehiscence, and 3 patients developed graft infections. Of the 141 implants, 121 integrated and 14 failed. There was a statistical difference between the losses of implants placed simultaneously versus nonsimultaneously (P = 0.003). The overall postloading success rate for dental implants reached 90% after a follow-up period between 12 and 120 months.The lateral window approach is associated with a high rate of success. Yet, some complications can influence the outcome of clinical treatment. Simultaneous placement of implants during sinus augmentation significantly affects their chance of success.