Dental Implant Migrates Into Sinus After 30 Years: A Rare Case of Peri-Implantitis Complication

The case report was published online in the International Journal of Oral Implantology on March 6, 2025.

An 87-year-old woman sought dental care after noticing looseness in her fixed partial denture. Upon clinical examination, the doctors discovered that an implant in the maxillary left second molar region was missing. Interestingly, the patient exhibited no symptoms of sinusitis, which is often associated with implant migration. Further imaging confirmed the dislocation of the implant into the maxillary sinus, accompanied by a pathological radiodensity.

To address the condition, a maxillary sinus revision procedure was performed under conscious sedation. The implant was carefully removed through a bone lid approach via the lateral sinus wall. Alongside the implant, a polypous mass was extracted and sent for histopathological examination. To ensure optimal healing, the affected area was thoroughly debrided and disinfected using 3% hydrogen peroxide and photodynamic decontamination. The resulting oroantral fistula was then sealed using a double-layer closure technique, incorporating a pedicled connective tissue flap and a mucoperiosteal flap.

Two months after the initial procedure, sinus floor elevation was performed using the layering technique, followed by the placement of a new implant. After a three-month healing period, the implant was exposed, and the final restoration was successfully placed six weeks later.

Histopathological analysis of the removed tissue confirmed the presence of chronic sinusitis with polyps. A follow-up CBCT scan conducted two months after surgery revealed a healthy sinus with an open ostium, indicating successful treatment. The subsequent implant placement and restoration process proceeded without complications.

The case emphasizes the long-term risks associated with peri-implantitis, particularly in the posterior maxilla, where bone loss can lead to implant instability and, in rare cases, migration into the sinus cavity. Regular monitoring of dental implants, early intervention for peri-implant infections, and proper maintenance are crucial in preventing such complications.

The successful management of this case demonstrates that implant dislocation into the maxillary sinus can be effectively treated through a bone lid approach combined with sinus revision. Additionally, this method allows for future bone grafting and implant placement, ensuring functional and aesthetic restoration for affected patients.

Reference:

Hampe, Tristan, and Fouad Khoury. "Implant Dislocation Into the Maxillary Sinus After 30 Years of Loading Due to Peri-implantitis: a Case Report." International Journal of Oral Implantology (Berlin, Germany), vol. 18, no. 1, 2025, pp. 59-68.