Horizontal alveolar ridge deficiencies may prevent the placement of dental implants and often require bone augmentation procedures before implant treatment. Two techniques commonly used for horizontal ridge augmentation are the Split Box Technique and the Split Bone Block Technique.

This retrospective study included patients treated at Marmara University Faculty of Dentistry between January 2014 and January 2026. Radiographic records were reviewed to evaluate bone gain after augmentation and the stability of the augmented bone during long-term follow-up. Implant survival after prosthetic rehabilitation was also assessed.

The purpose of this study was to compare the long-term outcomes of the Split Box Technique and the Split Bone Block Technique in terms of bone gain, bone stability, and implant survival.

Horizontal alveolar ridge deficiencies often require augmentation procedures before dental implant placement. Among the available augmentation methods, the Split Bone Block Technique (SBBT) and the Split Box Technique (SBT) are autogenous bone augmentation approaches designed to increase horizontal ridge width and facilitate implant-supported rehabilitation.

The aim of this retrospective study was to compare the radiological outcomes of SBBT and SBT with respect to horizontal bone gain, long-term bone stability, and implant survival. In addition, postoperative complications associated with both techniques were evaluated.

Patients treated between January 2014 and January 2026 at the Department of Oral and Maxillofacial Surgery, Marmara University Faculty of Dentistry, were retrospectively screened. Patients who underwent horizontal ridge augmentation using either SBBT or SBT and had complete radiographic follow-up records were included in the study.

Cone-beam computed tomography (CBCT) images obtained preoperatively, 6 months after augmentation, and during long-term follow-up after prosthetic rehabilitation were used to assess changes in horizontal bone width and graft stability. Radiological measurements were performed to evaluate bone gain after augmentation, dimensional changes during follow-up, and long-term maintenance of the augmented ridge.

The primary outcome measures were horizontal bone gain and long-term bone resorption. Secondary outcome measures included implant survival following definitive prosthetic rehabilitation and the occurrence of postoperative complications.

The study was designed to determine whether the Split Box Technique and the Split Bone Block Technique provide comparable long-term clinical and radiological outcomes for the treatment of horizontal alveolar ridge deficiencies prior to implant placement.

Inclusion Criteria:

• Age ≥18 years.
• Patients with horizontal alveolar ridge deficiency requiring horizontal ridge augmentation before implant placement.
• Patients treated with either the Split Box Technique (SBT) or Split Bone Block Technique (SBBT) at Marmara University Faculty of Dentistry between January 2014 and January 2026.
• Availability of complete radiographic records, including CBCT scans obtained preoperatively (T0), 6 months after augmentation (T1), and during long-term follow-up after prosthetic loading (T2).
• Availability of complete clinical records and follow-up data.

Exclusion Criteria:

• Incomplete clinical or radiographic records.
• Patients lost to follow-up.
• Presence of uncontrolled systemic diseases or conditions known to adversely affect bone healing.
• Use of medications known to interfere with bone metabolism or healing.
• Active infection at the augmentation site or complications that altered the planned treatment protocol.

The study population consisted of adult patients with horizontal alveolar ridge deficiencies who underwent horizontal ridge augmentation using either the Split Box Technique or the Split Bone Block Technique before implant placement. Patients were treated at Marmara University Faculty of Dentistry between January 2014 and January 2026 and had complete clinical records and CBCT imaging available for retrospective evaluation.