Trisi Paolo, Berardi Davide, Paolantonio Michele, Spoto Giuseppe, D'Addona Antonio, Perfetti Giorgio
Department of Stomatology and Oral Sciences, University "G. D'Annunzio" of Chieti, Chieti, Italy.
J Craniofac Surg. 2013 May;24(3):841-4. doi: 10.1097/SCS.0b013e31827c9e01.
Between implants and peri-implant bone, there should be a minimum gap, without micromotions over a threshold, which could cause resorption and fibrosis. The higher the implant insertion torque, the higher will be the initial stability. The aim was to evaluate in vitro the correlation between micromotions and insertion torque of implants in bone of different densities. The test was performed on bovine bone of hard, medium, and soft density: 150 implants were used, 10 for each torque (20, 35, 45, 70, and 100 N/cm). Samples were fixed on a loading device. On each sample, we applied a 25-N horizontal force. Insertion torque and micromotions are statistically correlated. In soft bone with an insertion force of 20 and 35 N/cm, the micromotion resulted significantly over the risk threshold, which was not found with an insertion force of 45 and 70 N/cm and in hard and medium bones with any insertion torque. The increase in insertion torque reduces the amount of micromotions between implant and bone. Therefore, the immediate loading may be considered a valid therapeutic choice, even in low-density bone, as long as at least 45 N/cm of insertion torque is reached.
在种植体与种植体周围骨组织之间，应存在最小间隙，且不存在超过阈值的微动，否则可能导致吸收和纤维化。种植体植入扭矩越高，初始稳定性越高。目的是在体外评估不同密度骨中种植体的微动与植入扭矩之间的相关性。该试验在硬、中、软密度的牛骨上进行：使用了150个种植体，每个扭矩（20、35、45、70和100 N/cm）使用10个。样本固定在加载装置上。在每个样本上，施加25 N的水平力。植入扭矩和微动在统计学上具有相关性。在软质骨中，当植入力为20和35 N/cm时，微动显著超过风险阈值，而在植入力为45和70 N/cm时以及在任何植入扭矩的硬质骨和中质骨中均未发现这种情况。植入扭矩的增加会减少种植体与骨之间的微动幅度。因此，即使在低密度骨中，只要达到至少45 N/cm的植入扭矩，即刻加载也可被视为一种有效的治疗选择。
