Autogenous dentin block versus bone block for horizontal alveolar ridge augmentation and staged implant placement: A randomized controlled clinical trial including histologic assessment

Objectives This study aimed to compare the dentin block (D-group) harvested from impacted wisdom teeth with autogenous ramus bone block (A-group) for horizontal alveolar ridge augmentation. Materials and methods Forty-two patients with anterior missing teeth and horizontal ridge defect were randomly assigned to two groups (n = 21 per group) to receive either dentin block group or autogenous bone block. Six months after the augmentation, dental implants were placed in all patients, and a core biopsy was performed for histological evaluation in addition to clinical and radiographic evaluation using cone beam computed tomography. The primary outcome was the mean overall clinical ridge width gain (CRWG) after 6 months of augmentation. Secondary outcomes were the overall radiographic ridge width gain (RRWG) after 6 months of augmentation and descriptive histological analysis with histomorphometric assessment of bone fraction %. Results All sites healed uneventfully, and the mean overall CRWG 6 months after augmentation was 3.52 +/- 0.56 mm and 2.24 +/- 0.86 mm in the D and A groups, respectively, with statistically significant difference between them (P <= .001). The overall mean RRWG was 3.61 +/- 0.61 mm and 3.41 +/- 1.15 mm in D and A groups, respectively, without any statistically significant difference between them (p = .062). The histomorphometric analysis of the bone area fraction was 42.6% and 41.3% in D and A groups, respectively, without any statistically significant difference between the two values (p = .89, Student's t-test). Histological evaluation in the D-group revealed new bone formation, viable cells, and matrix formation on the dentin block periphery, in addition to well-organized woven bone that suggests dentin block remodeling and supports new bone deposition. Conclusion The present clinical study revealed that dentin block may serve as an alternative graft to support horizontal alveolar ridge augmentation. Dentin blocks showed less resorption than autogenous bone blocks.