Experimental Research On Osseointegration Of Implant And New Bone Guided By Different Material

Object:This experiment is intended to provides a infratest reference for clinical patients with bone deficiencies and need guided bone regeneration technique for the restoration of bone and implant. Through the animal experiment comparing the integration ability of the implant and the new bone tissue guided by different materials, in different period of time, to confirm whether a good osseointegration can be formed, and time needed.Method:12healthy adult male Beagle dogs, prepare three cylindrical defect on the medial femoral condyle of bilateral hind(diameter8mm, height 1Omm):experimental group a filled with Bio-Oss, the experimental group b with β-tricalcium phosphate, and the experimental group c filled with autogenous bone as positive control group. Three months later, vertically insert DIO implants diameter3.8mm, length of10mm in the central of the bone grafting area. Put6dogs into death respectively in the fourth and twelfth week after implantation, remove the bone graft with the implant inside, and detect the osteogenic effect and bone bonding efficiency with X-ray and micro CT. All animal left leg specimens are used to hard tissue slicing, toluidine blue staining and methylene blue/acid fuchsin staining for histological observation; right leg specimens are used to the thrust test with universal mechanical testing machine and detection of biomechanical properties of bone combinationResults:1. X-ray observationAt4weeks, group a and group b, the bone density of the bone grafting area was significantly higher than that of normal bone, the bone substitute materials are phanerous, the bone trabecula structure was not obvious, low density image is visual at the implant-bone interface; group c, the bone density has no obvious difference with the surrounding normal bone, the bone trabecula structure is clear, part of low density image is still visible at the implant-bone interface. At12weeks, group a and group b, the bone density of the bone grafting area was slightly higher than the normal bone density, bone trabecula structure visible, BIC area increased; group c, bone grafting area has no boundary with the surrounding normal bone, bone trabecula structure is clear, orderly, bone tissue combined closely with the implant.2.Micro CT detectionBV/TV: at4weeks, no differences within three groups (F=1.673, P>0.05), at12weeks,group c> group b,(P<0.05);12weeks>4weeks,(P<0.05).Tb.Th: at4weeks, group c>group a, group c> group b, at12weeks, group c> group a> group b,(P<0.05);12weeks>4weeks,(P<0.01).Tb.Sp:at4weeks, no differences within three groups (F=2.333, P>0.05), at12weeks, group c<group a, group a<group b,(P<0.05);12weeks<4weeks,(P<0.05);Tb.N: at4weeks, group c> group a, group a> group b, at12weeks, group c> group a> group b,(P<0.05);12weeks>4weeks,(P<0.05).BIC:at4weeks, group c> group b, at12weeks, group a>b group, group c> group b,(P<0.05);12weeks>4weeks,(P<0.001).3. Histological observationAt4weeks, the bone-formation is active, the new bone trabecula is small, arrange irregularly, the incomplete absorbed bone substitute material particles is visible in group a and b; at12weeks, the number of osteoblast is reducing, bone trabecula is big, lots of mature lamellar bone arranged in an orderly manner, a small amount of bone substitute material particles is visible in a, b two groups, new bone tissue contact closely with the implant, the bone density of group b is slightly lower than that of group a and group c.BIC:at4weeks, group c> group b, at12weeks, group a>b group, group c> group b,(P<0.05);12weeks>4weeks,(P<0.001). 4. Biomechanical testingAt4weeks, the value of the implant launching, group c>group a>group b,(P<0.05); at12weeks, group a> group b, group c> group b,(P<0.05);12weeks>4weeks,(P<0.05).Conclusion:1.The experimental results showed, good osseointegration can be formed between implants and new bone tissues regenerated by guided bone regeneration technology in the bone defect area. And the binding effectiveness reaches the ideal effect in12weeks after implantation. Prosthesis is allowed at this time.2.Combining efficiency of new bone guided by Bio-oss and implant is better than that of β-tricalcium phosphate.