Immediate Implant Placement in the Mandibular Molar Septum Using Osseodensification: A Case Report with 4-Year Follow-Up.

Background and Clinical Significance: Immediate implant placement in mandibular molars represents a clinical challenge due to lower trabecular bone density and anatomical limitations of the interradicular septum. Osseodensification has been proposed as an alternative to improve primary stability in sites with low bone quality. Case Presentation: This report describes the case of a 54-year-old female patient with a mesial root fracture in the lower right first molar, treated by atraumatic extraction followed by immediate implant placement using a densifying drilling protocol. After careful root removal, the interradicular septum was expanded using Versah burs at 1200 rpm, allowing placement of a 4.0 × 7 mm Implacil Duecone implant with a final insertion torque of 25 Ncm. The residual gap was filled with a xenogeneic bone substitute and covered with a dense polytetrafluorethylene membrane for alveolar preservation. Healing progressed uneventfully and, after four months, adequate bone formation was observed, enabling prosthetic rehabilitation with a single ceramic crown. After 4 postoperative years we could find peri-implant tissue stability. Conclusions: The clinical outcome supports current evidence indicating that osseodensification may enhance initial stability and predictability of immediate implants placed in posterior mandibular regions.