The effectiveness of hydroxyapatite-beta tricalcium phosphate incorporated into stem cells from human exfoliated deciduous teeth for reconstruction of rat calvarial bone defects

Abstract

Objective: To investigate the effects of stem cells from the pulp of human exfoliated deciduous teeth (SHED) on biphasic calcium phosphate granules (BCP) to repair rat calvarial defects as compared to autogenous bone grafting.

Materials and methods: A defect with a 6-mm diameter was produced on the calvaria of 50 rats. BCP granules were incorporated into SHED cultures grown for 7 days in conventional (CM) or osteogenic (OM) culture media. The animals were allocated into 5 groups of 10, namely: clot, autogenous bone, BCP, BCP+SHED in CM (BCP-CM), and BCP+SHED in OM (BCP-OM). The presence of newly formed bone and residual biomaterial particles was assessed by histometric analysis after 4 and 8 weeks.

Results: The autogenous group showed the largest newly formed bone area at week 8 and in the entire experimental period, with a significant difference in relation to the other groups (P < 0.05). At week 8, BCP-CM and BCP-OM groups showed homogeneous new bone formation (P = 0.13). When considering the entire experimental period, the BCP group had the highest percentage of residual particle area, with no significant difference from the BCP-CM group (P = 0.06) and with a significant difference from the BCP-OM group (P = 0.01). BCP-CM and BCP-OM groups were homogeneous throughout the experimental period (P = 0.59).

Conclusions: BCP incorporated into SHED cultures showed promising outcomes, albeit less pronounced than autogenous grafting, for the repair of rat calvarial defects.

Clinical relevance: BCP incorporated into SHED cultures showed to be an alternative in view of the disadvantages to obtain autogenous bone graft.

Keywords: Biocompatible materials; Bone regeneration; Bone substitutes; Hydroxyapatite-beta tricalcium phosphate; SHED; Stem cells.