Zor Zeynep Fatma, Kılınç Yeliz, Erkmen Erkan, Kurt Ahmet
Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Gazi University, Ankara, Turkey.
Department of Manufacturing Engineering, Faculty of Engineering, Atılım University, Ankara, Turkey.
Technol Health Care. 2022;30(5):1031-1042. doi: 10.3233/THC-213072.
The effect of different thread designs and diameters on the all-on-four concept is unclear.
The aim of the study was to clarify the differences in stress distribution of dental implants with various thread designs and diameters based on the all-on-four concept with three dimensional (3D) finite element analysis (FEA).
A 3D model of a totally edentulous mandible was used to perform the FEA. Four different models (M1, M2, M3, and M4) including 3.5 and 4.3 mm diameter dental implants with active and passive threaded designs were generated. The dental implants were positioned according to the all-on-four concept. The Von Mises stresses on dental implants and maximum and minimum principal stresses (Pmax and Pmin) on bony structures were calculated under vertical, oblique and horizontal loads.
For Von Mises stresses, the highest stress values were detected on the distal implants for all models. Distal implants had also the highest stress values for vertical loading. The Von Mises stresses were found to be concentrated around the implant's neck. In all models the highest Pmax and Pmin stresses occurred in the bone surrounding the distal implant. It was noted that the active threaded implants showed the highest Pmax and Pmin stress values.
The implant thread design and diameter might have a strong influence on the stress values in the all-on-four concept.
不同螺纹设计和直径对全口四种植体理念的影响尚不清楚。
本研究的目的是基于全口四种植体理念，通过三维（3D）有限元分析（FEA）阐明不同螺纹设计和直径的牙种植体应力分布的差异。
使用无牙颌下颌骨的3D模型进行有限元分析。生成了四个不同的模型（M1、M2、M3和M4），包括直径为3.5和4.3mm的具有主动和被动螺纹设计的牙种植体。根据全口四种植体理念定位牙种植体。在垂直、倾斜和水平载荷下计算牙种植体上的冯·米塞斯应力以及骨结构上的最大和最小主应力（Pmax和Pmin）。
对于冯·米塞斯应力，所有模型中远端种植体上检测到的应力值最高。远端种植体在垂直载荷下也具有最高的应力值。发现冯·米塞斯应力集中在种植体颈部周围。在所有模型中，最高的Pmax和Pmin应力出现在远端种植体周围的骨中。值得注意的是，主动螺纹种植体显示出最高的Pmax和Pmin应力值。
种植体螺纹设计和直径可能对全口四种植体理念中的应力值有很大影响。
