目的:本研究旨在通过建立各向异性,三维(3D)有限元下颌骨模型,并模拟冠种植体比(CIR)对不同骨整合率的短种植体周围生物力学的影响。
方法:假设通过有限元方法骨骼是横向各向同性的,我们为下颌第一磨牙建立了四种不同的种植体模型.随后,轴向力和斜力被施加到这些模型的咬合面。最终,Abaqus2020软件用于计算各种机械参数,包括最大的冯·米塞斯压力,拉伸应力,压应力,剪切应力,位移,以及种植体周围骨组织的应变。
结果:在建立一致的骨整合率后,当承受垂直载荷时,应力分布在不同CIRs的模型中表现出相似性。然而,当暴露于倾斜载荷时,皮质骨内的最大vonMises应力随着CIR的升高而升高。在两种加载方案中,在aCIR为2.5,骨整合率为25%的模型中,最大vonMises应力显著升高.相反,其他型号显示出相当的强度。值得注意的是,在所有模型中,应力和应变值随着骨整合的增加而均匀增加。此外,骨整合率的增加与皮质骨和植入物的最大位移减少相关。
结论:固定骨整合率后,在倾斜载荷下,随着CIR的增加,较短植入物周围的应力增加。因此,选择较短的植入物时应考虑侧向力的影响。此外,在aCIR≥2.5且骨整合率低的情况下,存在植入失败风险.此外,骨整合率越高,植入物越容易实现稳固的稳定性。
This study aimed to provide evidence for the clinical application of single short implants by establishing an anisotropic, three-dimensional (3D) finite element mandible model and simulating the effect of crown-to-implant ratio (CIR) on biomechanics around short implants with different osseointegration rates.
Assuming that the bone is transversely isotropic by finite element method, we created four distinct models of implants for the mandibular first molar. Subsequently, axial and oblique forces were applied to the occlusal surface of these models. Ultimately, the Abaqus 2020 software was employed to compute various mechanical parameters, including the maximum von Mises stress, tensile stress, compressive stress, shear stress, displacement, and strains in the peri-implant bone tissue.
Upon establishing consistent osseointegration rates, the distribution of stress exhibited similarities across models with varying CIRs when subjected to vertical loads. However, when exposed to inclined loads, the maximum von Mises stress within the cortical bone escalated as the CIR heightened. Among both loading scenarios, notable escalation in the maximum von Mises stress occurred in the model featuring a CIR of 2.5 and an osseointegration rate of 25%. Conversely, other models displayed comparable strength. Notably, stress and strain values uniformly increased with augmented osseointegration across all models. Furthermore, an increase in osseointegration rate correlated with reduced maximum displacement for both cortical bone and implants.
After fixing osseointegration rates, the stress around shorter implants increased as the CIR increased under inclined loads. Thus, the effect of lateral forces should be considered when selecting shorter implants. Moreover, an implant failure risk was present in cases with a CIR ≥ 2.5 and low osseointegration rates. Additionally, the higher the osseointegration rate, the more readily the implant can achieve robust stability.