Effect Of Transforming Growth Factor-?3 Combined With Dental Pulp Stem Cells In Promoting The Implant's Osseointegration

Objective : To investigate the effect of transforming growth factor-?3 and Dental Pulp Stem Cells in promoting the implant?s osseointegration.Methods : DPSCs were isolated with tissue enzymetic digestion method to observe the morphology under light microscope.The third-passage DPSCs were cultured in vitro and refrigerated storage.36 experimental New Zealand rabbits were divided into PBS group,DPSCs group and the TGF-?3+DPSCs group randomly(12rabbits/group).Two teeth from the rabbits' s mandibular incisors and molars were pull out randomly,then implant were implanted in the tooth extraction wound immediately.In PBS group,the implant area was filled with Bio-Oss powder 0.30 g mixed by PBS 20 ul only;while the implant area was filled with Bio-oss powder 0.30 g and 1×108/L DPSCs 20 ul in DPSCs group;In the the TGF-?3+DPSCs group the implant area was filled with Bio-Oss powder 0.30g?1×108/L DPSCs 20 ul and 80ng/ul TGF-?3 20 ul.18 New Zealand rabbits were executed in the 4weeks and 8 weeks respectively.The treated alveolar bone tissue and implant were collected for plastic section.HE staining?ARS staining and immunohistochemical(IHC)detection of bone sialoprotein(BSP)?Osteocalcin(OC)and Type I collagen(COL-I)were performed after 4 weeks and 8 weeks.Combined bone lamelta width(CBLW)and implant bone contact rate(IBCR),trabecular width(TW)and trabecular area percentage(TA)wereobserved by histomorphometric measurement.Results The primary cultured immature DPSCs in rabbits grew in clones,were fusiform or fibrolbast liked.HE staining:4 weeks after surgery,the TGF-?3+DPSCs group was significantly stronger than the other two groups in the number of trabecular bone,osteoblast density,and new bone formation.8weeks after operation,the new bone formation increased.ARS staining: 4 weeks after the operation,the TGF-?3+DPSCs group showed more red calcified nodules than the other two groups;the red calcified nodule was further increased 8 weeks after operation.IHC: 4weeks after the operation,The expression of BSP,OC and COL-I was(0.35 ± 0.04),(0.36 ± 0.03)and(0.39 ± 0.01)respectively in TGF-?3+DPSC group,(0.27 ±0.02),(0.24 ± 0.01)and(0.28 ± 0.03)respectively in DPSCs group,and(0.13 ±0.03)gm,(0.15 ± 0.02)and(0.16 ± 0.02)respectively in PBS group.8 weeks after operation,The expression of BSP,OC and COL-I was(0.51 ± 0.02),(0.49 ± 0.03)and(0.53 ±0.02)respectively in TGF-?3+DPSC group,(0.35 ± 0.02),(0.37 ± 0.01)and(0.38 ± 0.01)respectively in DPSCs group,and(0.21 ± 0.03)gm,(0.19 ± 0.01)and(0.22 ± 0.02)respectively in PBS group.After 4 weeks and 8 weeks,the expression of BSP?OC and COL-I in TGF-?3+DPSCs group were significantly higher than the other groups(P < 0.05),there was no significant difference between DPSCs group and PBS group(P > 0.05).This suggests that the the TGF-?3+DPSCs group is more outstanding on the quality and quantity of new bone formation capacity than the other groups,and 8 weeks osseointegration was further enhanced.8 weeks after operation,The CBLW,IBCR,TW and TA around implant in TGF-?3+DPSCs group were significantly higher than the other groups(P < 0.05),there was no significant difference between DPSCs group and PBS group(P > 0.05).Conclusions : The DPSCs has strong proliferation ability and the potential osteogenic differentiation ability.TGF-?3 can accelerate the osteogenic differentiation of DPSCs to some extent.TGF-?3 combined with DPSCs can effectively promote the implant?s osseointegration.