Retrieval of Displaced Implant Attributable to an Ill-Fitting Denture From the Maxillary Sinus Six Months After Transcrestal Sinus Floor Augmentation and Implant Placement

Introduction: Asymptomatic displacement of dental implants into the maxillary sinus after a transcrestal sinus augmentation is a rare complication that can occur when there is poor bone quality and minimal residual bone height. Patient compliance with postoperative appointments and failure to comply with denture-wearing instructions are critical contributing factors. To the best of the authors’ knowledge, no cases of implant dislodgement attributable to a removable prosthesis have been reported in the literature, although some studies have suggested that improper occlusal forces can cause a longstanding implant to develop peri-implantitis and subsequent displacement of an implant into the sinus cavity. Case Presentation: A 71-year-old female presented 6 months after undergoing transcrestal sinus lift and implant surgery that involved a modified Summers technique using mineralized solvent-dehydrated cancellous bone allograft and placement of six maxillary implants. A displaced dental implant was retrieved from the right maxillary sinus, which had an intact Schneiderian membrane. The patient was asymptomatic and infection free. The displaced implant was accessed and retrieved via a lateral window sinus technique. No clinical signs of sinus infection were evident, and there were no additional complications during the 2-year follow-up period. Conclusion: This case report demonstrates a technique for the retrieval of implants that have been dislodged and migrated into themaxillary sinus cavity caused by an ill-fitting denture and improper masticatory forces. Clin Adv Periodontics 2016;6:175-181.