Abstract: This paper report a case of delayed implantation using staged ridge split combined with guided bone regeneration (GBR) in a patient with a knife-edge alveolar ridge due to free-end edentulism in the posterior mandible. For a patient with insufficient alveolar ridge crest width in the mandible who met the indications for ridge splitting, a two-stage ridge split was performed. The first surgery involved splitting the cortical bone to promote bone remodeling. One month later, a second ridge split was carried out with simultaneous implant placement, combined with GBR to achieve horizontal ridge augmentation. The horizontal alveolar bone width increased by 4~5 mm, meeting clinical requirements for implantation while reducing the risk of buccolingual implant exposure, minimizing surgical trauma, and shortening the treatment period. However, a two-year follow-up revealed buccal bone plate resorption in the surgical area at a rate of 0.1~0.3 mm/year. The staged ridge split technique provides a treatment option for patients with severe horizontal alveolar ridge deficiency (width≤3 mm) in the posterior mandible, but attention should be paid to the issue of long-term bone resorption.

Key words: Staged ridge split, Implant, Mandibular molar region, Alveolar ridge deficiency, Guided bone regeneration