Enhanced bone formation during healing process of tooth sockets filled with demineralized human dentine matrix

Background Orthodontic procedures are often limited by the presence of bone defects caused by trauma, periodontal diseases or surgeries, thus requiring the development of materials capable to compensate such deficiencies. Since bone morphogenetic proteins (BMPs) are indicative of bone reconstitution, this study aimed to evaluate histological and immunohistochemically the temporal location of BMP-2 and BMP-4 in osteoblasts of rat alveolar wounds filled with demineralized human dentine matrix (DHDM), used as a graft material. Methods After extraction of the upper second molars, the left side alveoli were filled with DHDM and the right side served as the control. The animals were euthanized after 3, 5, 10 and 14 days of surgery. After fixation, demineralization and paraffin embedding, representative samples of each group were stained with H&E and immunohistochemically evaluated. Results The data showed a statistically significant (p < 0.05) increased number of osteoblasts positively immunostained for BMP-2 and BMP-4 on the experimental side (left) at 10 days. Our results also showed that even when not degraded, dentine matrix was incorporated to new bone formation after 14 days of surgery. Conclusions The results suggest that DHDM acts as a scaffold for osteoblast differentiation, actively yielding new bone formation, and it may represent an effective bone implant material.