Turn-over of tibiae bone around dental implante using nuclear image

种植体周围的骨骼变化还没有完全阐明。本研究旨在通过骨显像揭示种植体周围骨代谢的动态变化。将实验性种植体植入Wistar大鼠的胫骨。为了观察骨代谢活动，使用伽马相机和改良的高分辨率针孔准直器(针孔直径：2 mm)拍摄颅骨闪烁照相。静脉注射99mTC-MDP(2mCI/只)。注射后2小时进行冠状方向静态平面采集。分别于植入后4d、1、2、3、4、5周摄片。种植体获得骨整合后，加载螺旋弹簧(100、150、200g)。分别于加载后4天、1、2、3、4周、5周进行摄像。计数99mTC-MDP在种植体周围和健侧胫骨中的蓄积情况。计算每组种植体周围的胫骨与完整部位的摄取率。研究表明，植入后7周，种植体部位的骨代谢恢复到与对侧完整部位相同的水平。99m-MDP在植入后7~12天在种植体周围积聚达高峰。不同负荷下种植体周围的摄取率不同。此外，加载到种植体后，种植体的载荷侧和牵引侧之间的差异有统计学意义。骨显像显示种植体周围的胫骨发生翻转，99mTC-MDP摄取活跃。

Bone changes around the dental implants have not been fully elucidated. This study amid to reveal the dynamic change of bone metabolism around the implant using bone scintigraphy. Experimental implants were inserted in the tibiae of Wister rats. To observe the bone metabolic activity, bone scintigraphy of the cranium was taken using a gamma-camera with a modified high-resolution pinhole collimator (diameter of the pinhole: 2mm). 99mTc-MDP was injected intravenously (2 mCi/rat). Static planer acquisition in coronal direction was executed at 2 hours after the injection. The image takings were made at 4 days, 1, 2, 3, 4 weeks and 5 weeks after the implant insertion. After obtaining osseointegration, implants were loaded with coil springs (100,150,200g). The image takings were also made at 4 days, 1, 2, 3, 4 weeks and 5 weeks after loadings. Accumulation of 99mTc-MDP to the tibiae bone around the implant and the contralateral intact site were counted. Uptake ratio of the tibiae bone around the implant to the intact, site was calculated in each group. The study revealed that bone metabolism at, the implant site was returned to the same level as the contralateral intact site at Sweeks after the insertion. High peak accumulation of 99m-MDP was seen around the implant at from 7 to 12 days after insertion. Uptake ratio around the implant was differing among the different kind of loading. Furthermore, there was significant difference between the loading side and the traction side of implant after loading to implants. Turn-over of the tibiae bone around the dental implant was demonstrated with the active uptake of 99mTc-MDP by bone scintigraphy.