Acemannan increased bone surface, bone volume, and bone density in a calvarial defect model in skeletally-mature rats

Background/purpose: Acemannan, a beta-(1e4)-acetylated polymannose extracted from Aloe vera gel, has been proposed as biomaterial for bone regeneration. The aim of this study was to investigate the effect of acemannan in calvarial defect healing. Materials and methods: Acemannan was processed to freeze-dried sponge form and disinfected by UV irradiation. Thirty-five female SpragueeDawley rats were used in the in vivo study. Seven-mm diameter mid-calvarial defects were created and randomly allocated into blood clot control (C), acemannan 1 mg (A1), 2 mg (A2), 4 mg (A4), and 8 mg (A8) groups (nZ7). After four weeks, the calvarial specimens were subjected to microcomputed tomography (microCT) and histopathological analysis. Results: MicroCT revealed a significant increase in bone surface and bone volume in the A1 and A2 groups, and tissue mineral density in the A4 and A8 groups compared with the control group (p < 0.05). Histologically, the acemannan-treated groups had denser bone matrix compared with the control group. Conclusion: Acemannan is an effective bioactive agent for bone regeneration, enhancing bone growth as assayed in two-and three-dimensions. (C) 2018 Association for Dental Sciences of the Republic of China. Publishing services by Elsevier B.V. This is an open access article under the CC BY-NC-ND license.