早期不同时间种植体骨界面改建的骨组织定量测定

Histomorphometry of implant-bone interface remodeling around dental implants during early phases of bone healing

目的建立种植体植入Beagle犬下颌骨的动物模型,应用Micro-CT对早期的种植体周围骨组织情况进行分析研究。方法选用4只健康纯系雄性Beagle犬,随机分A、B两组,拔除下颌双侧第4前磨牙、第1磨牙,3个月后在相应缺牙区植入8枚植体,分别在植入后2周、4周处死两只Beagle犬,并对其作相应临床检查及Micro-CT检测。结果各组实验犬拔牙创愈合良好,种植体成功植入相应拔牙位点,各项临床指标无明显差异,Micro-CT检测显示种植体植入后2周的骨体积分数大于植体植入后4周的骨体积分数,且两组具有显著统计学差异(P≤0.01),其余骨微结构计量无统计学差异。结论成功建立口腔种植Beagle犬动物实验模型,早期植体周围骨愈合是一个骨吸收骨生成的骨组织改建或骨组织修复过程,植体植入后4周其周围骨吸收大于骨生成,Micro-CT能很好地应用于口腔种植骨微结构分析研究。

Objective An animal model with dental implants put into Beagle dogs＇ mandible was established for the study of early phases of bone healing around implants with Micro-CT. Methods Four inbred healthy Beagle dogs were randomly divided into two groups ： group A and group B. The bilateral mandibular fourth premolars and first molars were extracted. Three months after extraction, eight dental implants were separately implanted in the corresponding teeth defect area, every 2 dogs were sacrificed at 2,4 weeks after the implantation, and the clinical presentation and Micro-CT detection were examined. Results The animals recovered without compli- cation, implants were successfully put into the corresponding teeth defect area, the clinical examination showed no significant diffe- rences, Micro-CT detection showed 6Bv/rv ratios of peri-implant bone after the implantation were greater for the group of 2 weeks com- pared with the group of 4 weeks, and the differences between the two groups had statistical significance （P ≤ 0.01 ）. However, there was no statistically significant difference between the rest of bone microstructure measurements around implants. Conclusion The animal model of Beagle dogs with normal implantation has been established successfully. Early phases of bone healing around titanium implants involve bone resorption and bone formation. 4 weeks after the implantation, bone resorption is greater than bone formation, and Micro- CT detection is a useful assessment for bone microstrueture measurements around implants.