AIM: To compare the dimensional stability of a self-retaining synthetic block bone (srBB) and synthetic bone particles (SBP) for alveolar ridge augmentation (ARA) in damaged extraction sockets. MATERIALS AND METHODS: ARA was randomly performed in two centres on 57 participants presenting damaged extraction socket in a non-molar tooth: (i) srBB and collagen membrane (srBB group, n = 29) or (ii) SBP and collagen membrane (SBP group, n = 28). Cone beam computed tomography (CBCT) was performed immediately after ARP (baseline, T0) and at 6 months (T1). T0 and T1 CBCTs were superimposed, and horizontal widths (H0-H5), vertical heights and volume changes were assessed using t-test. RESULTS: Due to wound dehiscence, srBB was removed in 10 patients. The change in horizontal width at the most coronal level (H0) was significantly lower for srBB compared to SBP (srBB: 0.8 ± 1.0 mm
SBP: 1.9 ± 2.2 mm, p <
0.05). Significantly less volume decrease was seen at the bucco-coronal level for srBB (srBB: 3.2 ± 0.6 mm CONCLUSION: Compared to synthetic bone particles, synthetic bone blocks have the potential to more effectively augment and maintain the coronal horizontal dimension and width of damaged extraction sockets for up to 6 months. However, this advantage is offset by their relatively high rates of early wound dehiscence. TRIAL REGISTRATION: Korean Clinical Research information service (CRIS) (KCT0005462).