Bone regeneration using composite non-demineralized xenogenic dentin with beta-tricalcium phosphate in experimental alveolar cleft repair in a rabbit model

Background: Alveolar cleft repair is performed via bone grafting procedure to restore the dental arch continuity. A suitable bone substitute materials should possess osteoinductive and osteoconductive properties, to promote new bone formation, along with a slowly resorbable scaffold that is subsequently replaced with functionally viable bone. Calcium phosphate biomaterials have long proved their efficacy as bone replacement materials. Dentin in several forms has also demonstrated its possibility to be used as bone graft replacement material in several studies. The purpose of this study was to evaluate bone regeneration pattern and quantify bone formation after grafting preestablished experimental alveolar clefts defects model in rabbits using composite xenogenic dentin and beta-TCP in comparison to beta-TCP alone. Methods: Unilateral alveolar cleft defects were created in 16 New Zealand rabbits according to previously described methodology. Alveolar clefts were allowed 8 weeks healing period. 8 defects were filled with beta-TCP, whereas 8 defects filled with composite xenogenic dentin with beta-TCP. Bone regeneration of the healed defects was compared at the 8 weeks after intervention. Quantification of bone formation was analyzed using micro-computed tomography (mu CT) and histomorphometric analysis. Results: mu CT and histomorphometric analysis revealed that defects filled with composite dentin/beta-TCP showed statistically higher bone volume fraction, bone mineral density and percentage residual graft volume when compared to beta-TCP alone. An improved surgical handling of the composite dentin/beta-TCP graft was also noted. Conclusions: Composite xenogenic dentin/beta-TCP putty expresses enhanced bone regeneration compared to beta-TCP alone in the reconstruction of rabbit alveolar clefts defects.