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A comparison between the efficacy of Bio-Oss, hydroxyapatite tricalcium phosphate and combination of mesenchymal stem cells in inducing bone regeneration.

BACKGROUND
Recently, tissue engineering has been introduced as a regenerative treatment for bone defects. There is some evidence showing bone regeneration from mesenchymal stem cells (MSC) loaded on hydroxyapatite β-tricalcium phosphate (HA/TCP) as a scaffold in large defects. This study aimed to compare the quality and quantity of regenerated bone using Bio-Oss, HA/TCP and MSC loaded HA/TCP scaffolds.


METHODS
Mesenchymal stem cells were aspirated from iliac crest bone marrow after extracting the first, second and third premolars and the first molar in five mature hybrid dogs. The cells were cultured and their osteogenic differentiation potential was evaluated after the third cell passage using Alizarin red staining in experimental conditions. The HA/TCP scaffold (3 × 3 × 3 mm) was loaded with undifferentiated mesenchymal stem cells. Bilateral bone defects were then prepared in the jaws using trephine burs. The defects were randomly filled with HA/TCP, Bio-Oss, or HA/TCP + MSCs. One defect served as a control and was left as an empty cavity. All defects except the control defect were covered with an absorbable membrane. Histological and histomorphometric evaluations were conducted after 6 weeks and data were subjected to analysis of variance (ANOVA) (p < 0.05).


RESULTS
The empty cavity demonstrated more bone formation (60.80%) than the HA/TCP (44.93%) and Bio-Oss (40.60%) (p < 0.05) groups. However, the difference from the HA/TCP + MSCs group was not significant (46.38%) (p > 0.05).


CONCLUSION
An MSC-loaded HA/TCP scaffold is a more effective alternative than Bio-OSS or HA/TCP in inducing bone regeneration.