Çelebi Bektaş Adalet, Yalçın Mustafa
Assistant Professor, Bingol University, Faculty of Dentistry, Department of Oral and Maxillofacial Surgery, Bingol, Turkey.
Associate Professor, Istanbul Kent University, Faculty of Dentistry, Department of Oral and Maxillofacial Surgery, Istanbul, Turkey.
J Stomatol Oral Maxillofac Surg. 2021 Dec;122(6):578-582. doi: 10.1016/j.jormas.2020.09.013. Epub 2020 Oct 1.
The aim of this study was to investigate deformation and stress distribution in the buccal lamellar bone via finite element analysis (FEA) in the application of alveolar ridge-splitting/expansion technique (ARST) in atrophic maxilla and mandible.
Three-dimensional (3D) solid models of maxilla and mandible were formed using computer software, with an alveolar ridge thickness of 4 mm in the right first molar region. In both models, one horizontal and two releasing vertical osteotomies were made in the atrophic region. Vertical forces varying from 50 N to 1000 N were continuously applied on the midpoint of the horizontal osteotomy and then the axial and total deformation and von Mises stress distribution in the buccal lamellar bone was assessed by FEA.
The degrees of axial deformation and total deformation and the maximum von Mises stress value under a 50 N force were 0.22 mm, 0.23 mm, and 4.52 MPa in the maxillary buccal lamellar bone and were 0.04 mm, 0.06 mm, and 5.90 MPa in the mandibular buccal lamellar bone, respectively. Similarly, under a 1000 N force, the values were 4.44 mm, 4.75 mm, and 90.49 MPa in the maxillary buccal lamellar bone and were 0.96 mm, 1.1 mm, and 118.02 MPa in the mandibular buccal lamellar bone, respectively.
These findings implicate that the ARST used for implant placement or alveolar augmentation can be achieved with the application of lower amounts of force in the maxilla compared to the mandible. It was also revealed that in ARST, the maximum von Mises stress value was lower in the maxillary buccal lamellar bone than in the mandibular buccal lamellar bone. Based on these findings, we consider that the administration of ARST could be biomechanically more stable in the maxilla than in the mandible.
本研究旨在通过有限元分析（FEA）研究牙槽嵴劈开/扩张技术（ARST）应用于萎缩性上颌骨和下颌骨时颊侧板层骨的变形和应力分布情况。
使用计算机软件构建上颌骨和下颌骨的三维（3D）实体模型，右侧第一磨牙区域的牙槽嵴厚度为4毫米。在两个模型的萎缩区域均制作一条水平截骨线和两条垂直松解截骨线。在水平截骨线中点持续施加50牛至1000牛不等的垂直力，然后通过有限元分析评估颊侧板层骨的轴向和总变形以及冯·米塞斯应力分布。
上颌颊侧板层骨在50牛力作用下的轴向变形程度、总变形程度和最大冯·米塞斯应力值分别为0.22毫米、0.23毫米和4.52兆帕，下颌颊侧板层骨分别为0.04毫米、0.06毫米和5.90兆帕。同样，在1000牛力作用下，上颌颊侧板层骨的数值分别为4.44毫米、4.75毫米和90.49兆帕，下颌颊侧板层骨分别为0.96毫米、1.1毫米和118.02兆帕。
这些研究结果表明，与下颌骨相比，在上颌骨中应用较低的力即可实现用于种植体植入或牙槽嵴增高的牙槽嵴劈开/扩张技术。研究还表明，在牙槽嵴劈开/扩张技术中，上颌颊侧板层骨的最大冯·米塞斯应力值低于下颌颊侧板层骨。基于这些研究结果，我们认为牙槽嵴劈开/扩张技术在上颌骨中的生物力学稳定性可能高于下颌骨。
