Complications After Implant Site Ridge Preservation and Delayed Implant Placement: A Case Report

The patient required removal of teeth #2 and #3 as a result of advanced bone loss and an endodontic–periodontic lesion at tooth #3. Case Presentation: The patient began taking metronidazole, 250 mg every 8 hours, 24 hours before surgery. Both teeth were extracted, and, after thorough debridement using curets and saline irrigation, their sockets were packed with bovine porous bone mineral covered by a dense polytetrafluoroethylene (PTFE) barrier secured with sutures. The barrier was removed at 1 month. After 6 months healing, two dental implants were placed using submerged technique. Four months later, the implants were uncovered and restored with cement‐retained crowns. The patient was contacted 1 year after restoration for reevaluation, at which time both implants showed bone loss. At site #2, a large subgingival cement deposit was seen in radiographs. At tooth #3, bone loss mirrored the original endodontic–periodontic lesion, suggesting that it had not been eradicated. Amoxicillin, 500 mg every 8 hours, was prescribed beginning 24 hours before surgery. The cement on implant #2 was removed, and the associated defect was debrided. Implant #3 was explanted, and its socket was debrided and regrafted using bovine porous bone mineral covered with calcium sulfate paste and then a dense PTFE barrier. The barrier was removed at 1 month, and the sites were allowed to heal for 7 months before replacing implant #3. The replacement crown for implant #3 was screw retained, and both implants appeared healthy 1 year later. Conclusion: Extraction site preservation grafting with xenograft and a barrier is an accepted treatment option but may on occasion result in complications, including failure of dental implants.