Zheng Lang, Luo Lailong, Chang Lulu, Ren Mingfa, Li Fangyuan, Liu Yang
Graduate School of Dalian University, Dalian, China.
Department of Engineering Mechanics, Dalian University of Technology, Dalian, China.
Int Dent J. 2025 Jun;75(3):2122-2131. doi: 10.1016/j.identj.2024.12.026. Epub 2025 Jan 7.
Implantation of the posterior maxilla with insufficient bone height faces challenges. Studies have shown that the use of ultrashort implants can avoid additional damage. This finite element analysis study aimed to evaluate the impacts of different lengths of ultrashort implants and three surgical approaches on stress, strain, and displacement in the posterior maxilla with varying bone heights.
Twelve models of different lengths (3.0, 4.0, 5.0, and 6.0 mm) of ultrashort implants combined with unicortical fixation, bicortical fixation, and transalveolar sinus elevation were established, and conventional implants and short implants were considered as control models. Von Mises stresses within the implants and the sinus floor cortical bone, maximum and minimum principal stresses within the alveolar ridge cortical bone, and the maximum principal strain of the cancellous bone were determined using these models. Additionally, the displacement of the implants was analysed.
Stress distribution range and peak values increased as implant length decreased. In the ultrashort implant group, H5L6 exhibited the smallest maximum and minimum principal stresses, 35.77 and 10.66 MPa, respectively. Among groups with different bone heights, 6 mm long implants presented the lowest maximum von Mises stress, whereas 3 mm long implants presented the highest.
In the posterior maxilla with bone heights of 3, 4, and 5 mm, the stresses in different lengths of ultrashort implants and surrounding bone tissue were lower than the yield strengths in these areas, and the use of 6 mm-long ultrashort implants combined with osteotome sinus floor elevation can achieve lower stress distribution.
This study provides important insights into the biomechanical properties of ultrashort implants combined with three different surgical procedures in severely atrophic maxilla. The 6-mm long implant combined with osteotome sinus floor elevation is most suitable for this area.
在上颌骨后部骨高度不足的情况下进行种植面临挑战。研究表明，使用超短种植体可避免额外损伤。本有限元分析研究旨在评估不同长度的超短种植体及三种手术方法对上颌骨后部不同骨高度区域的应力、应变和位移的影响。
建立12个不同长度（3.0、4.0、5.0和6.0毫米）的超短种植体模型，分别采用单皮质固定、双皮质固定和经牙槽嵴窦底提升术，并将传统种植体和短种植体作为对照模型。利用这些模型确定种植体内和窦底皮质骨内的冯·米塞斯应力、牙槽嵴皮质骨内的最大和最小主应力以及松质骨的最大主应变。此外，分析种植体的位移情况。
随着种植体长度的减小，应力分布范围和峰值增大。在超短种植体组中，H5L6的最大和最小主应力最小，分别为35.77和10.66兆帕。在不同骨高度组中，6毫米长的种植体呈现出最低的最大冯·米塞斯应力，而3毫米长的种植体呈现出最高值。
在上颌骨后部骨高度为3、4和5毫米时，不同长度的超短种植体及其周围骨组织中的应力低于这些区域的屈服强度，使用6毫米长的超短种植体结合骨凿窦底提升术可实现更低的应力分布。
本研究为严重萎缩上颌骨中结合三种不同手术方法的超短种植体的生物力学特性提供了重要见解。6毫米长的种植体结合骨凿窦底提升术最适合该区域。
