Using a Single-Screw Cortical Disc for a Simplified Shell Technique: A Novel Approach and Technical Note

Cureus. 2025 Jun 21;17(6):e86475. doi: 10.7759/cureus.86475. eCollection 2025 Jun.

Abstract

Background One of the notable challenges in implant dentistry is the inadequacy of bone dimensions. While guided bone regeneration remains the standard approach for horizontal bone reconstruction, emerging new approaches such as the shell technique offer the potential for significant bone gain through effective space creation. This article presents a modified shell technique as a promising and practitioner-friendly solution for managing horizontal bone deficiencies before and during implant placement. This article aims to introduce a simplified and minimally invasive approach that enhances space maintenance and surgical management and allows for extraoral screw fixation to the disc with just a single screw. Methodology This study included six patients with horizontal bone defects that made them candidates for bone augmentation procedures. We employed a newly modified shell technique utilizing a single-screw cortical disc. The cortical discs were fabricated from cortical plates using a trephine drill and Cortico-Cage device. A titanium screw was secured extraorally to the cortical disc. The assembly of the screw and disc was anchored bi-cortically in the appropriate position, and the gap between the cortical disc and the underlying bone bed was filled with a combination of autogenous chips and allograft material. This simplified shell technique is designed to facilitate bone augmentation in areas with horizontal bone deficiencies. Results Cone-beam computed tomography assessments performed five months postoperatively in five cases demonstrated that the increase in bone width at the crestal area, specifically at the site of cortical discs, ranged from a minimum of 2.03 mm to a maximum of 5.76 mm. Moreover, the initial bone width before reconstruction in the evaluated cases ranged from a minimum of 1.74 mm to a maximum of 4.40 mm. Radiographs before and after the procedure indicated a noteworthy bone formation. Conclusions The findings suggest that employing a single screw to secure the cortical disc while connecting it to the disc outside of the patient's oral cavity can facilitate the surgical process and enhance patient comfort.

Keywords: allograft; alveolar ridge augmentation; bone graft; cortical bone plate; dental implants; shell technique.