牙种植体周围骨缺损引导骨组织再生后骨结合的生物力学研究

Evaluation the osseointegration which the dental implants surrounding bone defect were treated with GBR by biomechanics test

目的:通过生物力学测试,观察、分析和评价两种异种骨移植材料在牙种植体周围骨缺损中引导骨组织再生后种植体与骨的结合强度,为临床应用提供参考。方法:成年比格犬两只,每只犬的四肢股骨中分别植入24枚种植体(每侧股骨6枚),共48枚。再用裂钻在近心端1--4号种植体远中制作一5mm直径的圆形骨缺损并分别用两种异种骨移植材料在牙种植体周围骨缺损中引导骨组织再生。手术后6个月处死动物。摄x线片观察,并用万能力学实验机通过推出、拉出实验测试种植体-骨结合力、通过扭矩实验测试种植体-骨界面的结合强度。结果:三组种植体和骨界面x线表现相似,均有新骨形成;Bio—OSS组骨的结合强度要略高于天博骨粉组,两者无显著性差异(P>0.05);但两者与正常对照组均有差异。结论:两种异种骨移植材料均可较好的引导种植体周围骨缺损中骨组织再生,但实验组与对照组的生物力学测试结果有显著性差异(P<0.01)。提醒我们在种植体周围骨缺损区引导组织再生后早期临床负载方式的选择仍需谨慎。

Objective:The aim of this study was to analyse and evaluate the osseointegration by biomechanics test between implants and bone in which the dental implant surrounding bone defects were treated with GBR(Guided bone regeneration,GBR).Methods:Three groups of 48 dental implants(3.3mm in diameter,11mm in lenth),were placed in the femurs of two adult beagle dogs,six implants in each femur names 1-6. The 1-4 implants surrounding bone defects were made and treated respectively with two kinds of materials by GBR. Both dogs were euthanized after undisturbed healing for 6 months. The specimens were evaluation with radiograph. The strength of osseointegration were measured separately by push-out test,pull-out test and removal torque test.Results:There is no difference of three groups evaluated with X-ray. Both groups that treated by GBR with two different bone materials had new bone formation. The shear strength of group A (treated by GBR with Bio-OSS) was higher than group B(treated by GBR with Tianbo Coral bone). But there was no significant difference between the two groups(P>0.05). Both group A and group B had significant difference with group C (control group)(P<0.01).Conclusion:It has good results that the dental implant surrounding defects were treated by GBR with the two kinds of different bone material. The results of biomechanics test had significant difference between either of the test groups and matched cotrol group (P<0.01). It reminded that the style of implant loading in the early must be very carefully.