The effect of bone particle size on the histomorphometric and clinical outcomes following lateral ridge augmentation procedures. A randomized double blinded controlled trial

The aim of this randomized clinical trial was to clinically and histologically compare the amount and quality of bone gained after lateral ridge augmentation (LRA) procedures performed using small (250-1000μm) versus large (1000-2000μm) particle size cortico-cancellous bone allografts at 6 months following surgical intervention.22 patients, each presenting with ridge width less than 5mm were enrolled. Patients were randomly allocated to small (SP) and large particle (LP) size graft. The gain in ridge width at the level of the crest and 4mm apical to the crest was assessed via a standardized procedure before grafting and at time of implant placement, using a surgical caliper and a novel digital technique using cone beam computed tomography (CBCT). Six months following the procedure, trephine bone cores were taken from 19 augmented sites out of 17 patients (14/19 sites were in the posterior mandible) who completed the study for clinical, histologic and histomorphometric analysis.17 patients (19 sites) completed the study. LP size graft resulted in greater ridge width gain at the level of the crest (LP, 5.1 ± 1.7; SP, 3.7 ± 1.3 mm; p = 0.0642) and 4mm apical to the crest (LP, 5.9 ± 2.2; SP, 5.1 ± 1.8 mm; p = 0.4480) compared with the SP. No statistical significance for the bone density at the time of implant placement (p = 1.00) was found. Vital bone formation was more extensive in the SP compared with the LP 41.0 ± 10.1% vs 31.4 ± 14.8%, respectively (p = 0.05).The results of the present article show a trend of higher ridge gain using LP during bone augmentation procedure. Future research with bigger sample size should confirm the results of the present article. This article is protected by copyright. All rights reserved.Different size particles of allografts can be used safely and effectively for LRA without significant differences in clinically or histological outcomes.