Abstract:

Objective

To observe the effects of lanthanum chloride （La³⁺） on the osteogenesis of tissue-engineering bone implanted into the autologous bony defects in dog jaws.

Methods

Bone marrow stromal cells （BMSCs） from femoral bone marrow of 9 dogs were separated by density gradient centrifugation， cultured in vitro and induced to be osteoblast. The third generation BMSCs were interfered with La³⁺ of 5.564 μg/ml and combined with the pig freeze-dried demineralize bone matrix （fdDBM）， incubated in vitro for 7 days and then grafted into the autologous bony defects （2 cm×1 cm ×0.8 cm） of dog jaws. BMSCs-fdDBM， unseeded fdDBM and empty defects served as control groups. At 3 and 6 monthes after operation，the dogs were sacrificed and the implanted site of the jaws were harvested. The specimens were processed for morphological observation and radiographic bone-density analysis. The data was analyzed by SAS 6.12 software for ANOVA.

Results

New osteoid structure could be observed through histological exam of all the specimen of all groups. The density values of new bone in the implanting area treated with La³⁺ was higher but there was no obvious statistic significance as compared with that of the control groups. 6 monthes later， the density values of new bone in BMSCs-fdDBM group and fdDBM group had no obvious difference （P＞ 0.05） but were significantly higher than that of empty control groups （P＜0.05）.

Conclusion

La³⁺ at the concentation of 5.564 μg/ml has no obvious negative effect on osteogenesis of tissue engineering bone.

Key words: Bone marrow stromal cells （BMSCs）, Tissue-engineering-bone, Lanthanum chloride （La³⁺）, Freeze-dried demineralized bone matrix （fdDBM）