Radiological findings of the post-sinus lift maxillary sinus: A computerized tomography follow-up

The purpose of this paper is to present radiological findings of a short-term (8 to 10 months) computerized tomography (CT) follow-up study on 1-stage maxillary sinus lift cases. Pre- and postoperative dental CT scans of 21 patients (24 sinuses) after sinus lift procedures were compared. CT scans were used to assess newly formed bone and its interface with the implants, condition of the sinus membrane, evidence of buccal window cortication, and presence of any sinus pathology. Of the 57 implants placed, 28 had bone fully covering the implant on all sides which did not extend above the apical portion; 20 had bone fully covering the implant which did extend above the apex; and 9 exhibited incomplete bone coverage. All implants supported a fixed ceramo-metal prosthesis, and no implant failures were recorded after 3 years of follow-up. There was evidence of cortication of the buccal window in 10 sinuses; in the 14 remaining sinuses, bone consolidation on the buccal aspect was evident, but no evidence of cortication was seen. All sinuses healed without complications or clinical signs of sinusitis. In 11 sinuses, no changes in membrane thickness were noted. Membrane thickness decreased postoperatively in 12 sinuses, and in one, there was evidence of membrane thickening. Bone cortication in the anterior wall window may serve as an indicator for the remodeling status of the entire graft. Postoperative findings showed a significant improvement in overall membrane thickness. No clinical symptoms of sinusitis were evident, indicating that sinus lift procedures can be considered safe and do not predispose the sinus to acute or chronic sinusitis. J Periodontol 1999;70:1564-1573.