Study On The Effect Of TGF-?₃ With DPSC_s In Repairing Of Animal Bone Defect In Implantation Area

Objective:To establish an animal experimental model of the immediate implantation for peri-implant bone defects of the rabbit mandibular anterior teeth,and observe the osteogenetic capability of dental pulp stem cells?DPSC_s?and TGF-?₃.Method: 1 Separated DPSC_s from dental pulp tissues of young New Zealand rabbits for in-vitro culture;2 randomly divided 30 New Zealand rabbits for experiment into three groups,i.e.blank group,control group and experimental group,with 10 rabbits in each one.Then,pulled out the right-lower front teeth of the animals of the three groups and artificially prepared 2*2 mm bone defect area on the labial side.Then,filled 0.10 g of coarse-particle Bio-oss plus 20 ?L of PBS into the bone defect areas of the animals of the blank group;filled 0.10 g coarse particle Bio-oss plus 20 ?L of 1×108/L DPSC_s into the bone defect areas of the animals of the blank group,and filled 0.10 g of coarse particle Bio-oss plus 20 ?L of 80ng/?LTGF-?₃ plus 20 ?L of 1×108 /L DPSC_s into the bone defect areas of the animals of the experimental group.Killed five animals four weeks after the operations and another five animals eight weeks after the operations,and observed the bone regeneration capacities of the animals of the three groups through electron microscope scanning,specific staining and micro-CT.Results: 1 A few primarily cultured dental pulp cells of young rabbits were in spindle or polygon shape while most of the cells were fibroblast-shaped ones;2 electron microscope scanning: Four weeks after the operations,for the blank group,there was no evident bone trabecula formation;for the control group,a few osteoblasts and newly generated bone lamella could be seen around the bone defect area;for the experimental group,a large number of blood capillaries and osteoblasts as well as an evident increase of newly generated bone lamella could be seen in the bone defect area.Eight weeks after the operations,for the blank group,osteoblasts and newly generated bone trabecula could been seen around the materials yet within a limited area;for the control group,a small amount of newly generated bone could be seen but there was a boundary between old bone and newly generated one;for the experimental group,the bone defect area aroundthe implanted body was filled with a large amount of newly generated bone tissues and the boundary between the original bone and the newly generated one was not evident.3Specific staining: Four weeks after the operations,for the experimental group,newly generated bone with fairly consecutive parts could be seen in the bone defect area around the implanted body;for the control group,newly generated yet inconsecutive bone could be seen;for the blank group,no newly generated bone tissues could be seen in the bone defect area.Eight weeks after the operations,for the experimental group,it could be seen that the newly generated bone tissues merged with original bone in the bone defect area;for the control group,newly generated consecutive bone tissues could be seen in the bone defect area but had not merged with the original bone;for the blank group,newly generated bone tissues could also be seen but had not been up to osseointegration.4Micro-CT: Four weeks and eight weeks after the operations,there was significant difference?P<0.05?in BV/TV and Tb.Th for the three groups.Conclusion: 1 Exogenous TGF-?₃ and dental pulp stem cell could effectively promote bone defect repair;2 exogenous TGF-?₃ and dental pulp stem cell could accelerate osseointegration,thus providing certain theoretical basis for later-stage clinical experiment.