Objective: The aim of this study was to investigate whether dental implant exposure to the maxillary sinus cavity increased the risk of maxillary sinus complications.
Study design: Nine patients with 23 implants that had been inserted into the maxillary sinus more than 4 mm without lifting the sinus mucous membranes were evaluated for sinus complications 6 to 10 months after implant insertion, using a questionnaire and computerized tomography (CT).
Results: There were no clinical signs of sinusitis in any patient. However, CT scans showed postoperative sinus mucous thickening around 14 of the 23 implants.
Conclusion: This study showed that implant exposure to the maxillary sinus cavity can cause sinus mucous thickening around the implants.