Addition of autogenous bone chips to deproteinized bovine bone mineral does not have additional benefit in lateral ridge augmentation—A preclinical in vivo experimental study

Objective: To compare the outcome after extensive lateral guided bone regeneration using deproteinized bovine bone mineral (DBBM) with or without autogenous bone chips in a canine model of chronic horizontal alveolar ridge defect. Materials and Methods: The second, third and fourth lower premolars of both sides were extracted, and the buccal bone walls were completely removed in five beagle dogs. After 4 weeks, DBBM particles mixed with autogenous bone chips at a ratio of 1:1 were grafted at one side (DBBM/Auto group), while DBBM particles alone were grafted at the contralateral side (DBBM group). The graft materials on both sides were covered by a resorbable collagen membrane and fixation pins. Microcomputed tomographic volume and histomorphometric analyses were performed at 16 weeks post-surgery. Results: The ridges of both groups were recovered horizontally, but new bone formation beyond the original ridge contour at the defect site was not found. The DBBM group exhibited a larger total radiographic augmented volume and new bone volume compared with the DBBM/Auto group, but the differences were minimal (p >.05). Histologically, the regenerated area and new bone area were also slightly larger without any statistical significance in the DBBM group than in the DBBM/Auto group (p >.05). Conclusion: The addition of autogenous bone chips to DBBM for lateral ridge augmentation may confer no advantage over grafting DBBM alone with respect to both space maintenance and de novo bone formation in dogs.