Implantation of green tea catechin α-tricalcium phosphate combination enhances bone repair in rat skull defects

The purpose of the present study is to investigate effects of the combination of epigallocatechin-3-gallate (EGCG) and a-tricalcium phosphate (a-TCP) on bone regenerative capacity in a bilateral rat calvarial bone defect model. Materials and methods: Bilateral 5-mm-diameter calvarial defects were created in adult male Wistar rats and filled with preparations of EGCG (0, 0.1, 0.2, 0.4 mg) combined with aTCP particles. This was done by dissolving EGCG in 100% ethanol (50 lL/14 mg) and dropping under sterile condition. The control group was left unfilled (n = 8). The animals were sacrificed at 2 and 4 weeks. Radiological images were taken, and histological analysis was done. Six animals from control (0 mg EGCG+alpha-TCP) group and (0.2 mg EGCG+alpha-TCP) group were labeled with fluorescent dyes and histomorphometrically analyzed (n = 6) at 2 and 4 weeks. Results: Histo-morphometric analysis revealed that the combination of EGCG and alpha-TCP at doses of 0.1 and 0.2 mg yielded significantly more new bone formation than untreated control group at 2 and 4 weeks (p < 0.05). Mineral apposition rate at 0.2-TCP group was enhanced compared with the one of the positive control alpha-TCP group at 4 weeks (p < 0.05). Conclusion: The combination of alpha-TCP particles and 0.2 mg EGCG stimulates maximum bone regeneration in rat calvarial defects, and this combination would be potentially effective as bone graft material. (C) 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 98B: 263-271, 2011.