Department of Oral Implantology, School of Stomatology, Fourth Military Medical University, Xi'an, Shaanxi, China.
J Oral Rehabil. 2009 Apr;36(4):284-91. doi: 10.1111/j.1365-2842.2009.01936.x. Epub 2009 Feb 7.
The purpose of this study was to investigate influences of buccal bi-cortical anchorages on natural frequency (NF) values of dental implants in different diameters utilizing the three-dimensional finite element method. Three degrees of buccal bi-cortical engagements were generated in D2 and D3 bone quality models, which were 0-mm engagement (i.e. implants just had contact with the buccal cortex), 0.5-mm (i.e. implants were penetrated into the buccal cortex by 0.5 mm) and 1.0-mm engagement, while only 0- and 0.5-mm engagement were simulated in D4 bone models. The uni-cortical engagement was set as the control. By the modal analysis, NF values of bending and axial vibration mode were computed as a function of different bi-cortical engagements. The results showed that buccal bi-cortical anchorages significantly enhanced bending and axial NF values. The increasing rates resulting from 0.5-mm engagement ranged from 10.5 to 42.3%, with a mean of 24.3%. From 0- to 0.5-mm engagement, the NF values maintained an increasing trend, and from 0.5- to 1.0-mm engagement, the values levelled off or even decreased. In 0.5- and 1.0-mm engagement models, increasing implant diameter resulted in small increases of NF values. In conclusion, buccal bi-cortical anchorages could significantly increase both bending and axial NF values of dental implants, but extra-buccal cortical bone engagement could not produce considerable incremental increases of NF values as anticipated. Increasing implant diameter could result in limited increases of NF values in case of implants being bi-cortically anchored.
本研究旨在利用三维有限元方法研究不同直径的颊侧双皮质固位对种植体固有频率（NF）值的影响。在 D2 和 D3 骨质量模型中生成了三种颊侧双皮质嵌合度，即 0 毫米嵌合（即种植体仅与颊侧皮质接触）、0.5 毫米嵌合（即种植体向颊侧皮质内穿透 0.5 毫米）和 1.0 毫米嵌合，而在 D4 骨模型中仅模拟了 0-和 0.5 毫米嵌合。单皮质嵌合被设置为对照。通过模态分析，计算了弯曲和轴向振动模式的 NF 值，作为不同双皮质嵌合的函数。结果表明，颊侧双皮质固位显著提高了弯曲和轴向 NF 值。0.5 毫米嵌合引起的增长率范围为 10.5%至 42.3%，平均值为 24.3%。从 0-0.5 毫米嵌合，NF 值保持增加趋势，从 0.5-1.0 毫米嵌合，值趋于平稳甚至下降。在 0.5-和 1.0 毫米嵌合模型中，增加种植体直径导致 NF 值略有增加。总之，颊侧双皮质固位可显著提高种植体的弯曲和轴向 NF 值，但超出颊侧皮质骨的嵌合并不能如预期那样产生可观的 NF 值增量增加。在种植体双皮质固位的情况下，增加种植体直径可能会导致 NF 值的有限增加。
