这个数值分析,通过采用Tresca和VonMises失效准则,评估了在五次运动(侵入,挤压,小费,旋转,和平移)以及在逐渐的水平牙周破裂(0-8毫米)期间。此外,他们评估了骨质流失产生的变化,以及缺血和吸收风险。该分析在405个模拟中采用了9名患者的81个模型。两种失效标准均显示出相似的定性结果,Tresca在数量上高出1.09-1.21。三种正畸负荷之间没有定性差异。定量地,与0.6N相比,可以看到加倍(1.2N)和四倍(2.4N)。旋转和平移,然后翻倒是压力最大的,特别是对于减少的牙周组织,容易出现较高的缺血和吸收风险。在完整的牙周组织中,可以安全地使用1.2N,但只能在减少的牙周组织中进行挤压和侵入。超过0.6N容易增加其他三种运动的缺血和再吸收风险。在完整的牙周组织中,应力在整个小梁结构中传播。在牙周组织减少的情况下,应力集中(在4mm的应力变化分布损失标记之后),并在剩余的牙槽窝的子宫颈三分之一处增加。
This numerical analysis, by employing Tresca and Von Mises failure criteria, assessed the biomechanical behavior of a trabecular bone component subjected to 0.6, 1.2, and 2.4 N orthodontic forces under five movements (intrusion, extrusion, tipping, rotation, and translation) and during a gradual horizontal periodontal breakdown (0-8 mm). Additionally, they assessed the changes produced by bone loss, and the ischemic and resorptive risks. The analysis employed eighty-one models of nine patients in 405 simulations. Both failure criteria showed similar qualitative results, with Tresca being quantitatively higher by 1.09-1.21. No qualitative differences were seen between the three orthodontic loads. Quantitatively, a doubling (1.2 N) and quadrupling (2.4 N) were visible when compared to 0.6 N. Rotation and translation followed by tipping are the most stressful, especially for a reduced periodontium, prone to higher ischemic and resorptive risks. In an intact periodontium, 1.2 N can be safely applied but only in a reduced periodontium for extrusion and intrusion. More than 0.6 N is prone to increasing ischemic and resorptive risks for the other three movements. In an intact periodontium, stress spreads in the entire trabecular structure. In a reduced periodontium, stress concentrates (after a 4 mm loss-marker for the stress change distribution) and increases around the cervical third of the remaining alveolar socket.