Gelfoam haemostatic agent with or without autologous bone marrow-derived stem cells for the regeneration of critical-size mandibular defects in the rabbit

This study evaluated the effect of Gelfoam sponge with and without autologous bone marrow-derived stem cells (BMSCs) on bone regeneration in critical-size mandibular defects. The study involved 56 New Zealand rabbits assigned to four groups (14 in each). The osseous defects in group I were irrigated with normal saline, those in group II were grafted with autogenous tibial bone, and those in group III were filled with Gelfoam sponge. Group IV defects were treated as for group III, but the interface between the Gelfoam sponge and bone surface was injected with BMSCs. At the end of 4 weeks, seven rabbits in each group were euthanized; the remaining animals were euthanized at the end of the experiment, at 8 weeks postoperative. The percentage area of newly formed bone was significantly higher in group IV at week 4 (0.030 ± 0.01%) and week 8 (0.060 ± 0.03%) than in group I (0.01 ± 0.00% and 0.02 ± 0.00%, respectively) and group III (0.08 ± 0.01% and 0.015 ± 0.02%, respectively), but was lower than that in group II (0.038 ± 0.02% and 0.082 ± 0.01%, respectively). Thus, the combination of Gelfoam and autologous BMSCs promoted the regeneration of mandibular critical-size defects better than the use of Gelfoam alone. However, the amount of newly generated bone was lower than in defects grafted with autogenous bone.