Digitally Guided Augmentation With an Autogenous Bone Cylinder-Digital CarroTrack Technique: A Case Report

This case report presents the surgical and prosthetic treatment of posterior mandibular tooth loss using a digitally guided augmentation technique with an autogenous bone cylinder, referred to as the Digital CarroTrack Technique. The method represents a digital modification of the autogenous bone cylinder harvesting technique (carrot technique) described by Khoury and integrates implant planning with guided bone augmentation. A 33-year-old female patient presented for implant-prosthetic rehabilitation of missing mandibular molars following previous orthodontic treatment. Diagnostic assessment included CBCT imaging, intraoral scanning, and clinical examination. Implant placement at Sites #36 and #46 was digitally planned using dedicated software, and a surgical guide incorporating sleeves for implant drills, trephine drills, and stabilizing screw placement was designed. Bone cylinders were harvested using a trephine guided through the custom-designed sleeve and stabilized laterally to the implant sites with fixation screws, followed by augmentation with a bone substitute material. After a 3-month healing period, digital impressions were obtained, and screw-retained zirconia crowns on Ti-base abutments were fabricated and delivered. Radiographic and clinical evaluation confirmed successful bone reconstruction and stable peri-implant tissues. Stabilizing screws were removed during a follow-up visit using a minimally invasive approach. Three-year follow-up demonstrated stable hard and soft tissues and satisfactory functional and aesthetic outcomes. The presented technique enables precise integration of digital implant planning with localized autogenous bone augmentation and may represent a minimally invasive approach for the reconstruction of small alveolar ridge deficiencies in implant dentistry.