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

种植体周围的骨变化尚未完全阐明。本研究旨在利用骨显像技术揭示种植体周围骨代谢的动态变化。在Wister大鼠胫骨内植入实验性植入物。为了观察骨代谢活动，使用带有改进的高分辨率针孔准直仪（针孔直径2mm）的伽马照相机对颅骨进行骨闪烁成像。99mTc-MDP静脉注射（2 mCi/大鼠）。在注入后2小时进行冠状方向的静态刨床采集。分别于植入后第4天、第1周、第2周、第3周、第4周和第5周取像。获得骨整合后，植入物加载螺旋弹簧（100,150,200g）。在加载后第4天、第1、2、3、4周和第5周进行图像采集。计算99mTc-MDP在种植体周围胫骨及对侧完整部位的累积量。计算各组种植体周围胫骨对完整部位的摄取比。研究显示，植入后5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。植入后7 ~ 12天，植入物周围出现99m-MDP的峰值积累。种植体周围的摄取比在不同的载荷下是不同的。此外，种植体加载到种植体后，其加载侧与牵引侧存在显著差异。骨显像显示种植体周围的胫骨发生翻转，99mTc-MDP被主动摄取。

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.