Deniz Berivan, Yurttutan Mehmet Emre
Department of Oral and Maxillofacial Surgery, Ankara University, Faculty of Dentistry, Emniyet, Mevlana Blv, 19/1, Ankara, Yenimahalle, 06560, Turkey.
BMC Oral Health. 2025 Jul 2;25(1):1038. doi: 10.1186/s12903-025-06387-3.
This study aims to evaluate the stress distribution under occlusal forces by using finite element analysis (FEA) to compare conventional, zygomatic, and differently designed subperiosteal implants (SI) in edentulous atrophic maxilla.
A 3D model of an edentulous atrophic maxilla was reconstructed from CT scans. Three models were simulated: Model 1 with zygoma and conventional implants, Model 2 with apertura piriformis and subperiosteal implants extending to the zygomaticomaxillary buttress, and Model 3 with apertura piriformis and subperiosteal implants covering the zygomatic buttress. Mechanical properties were assigned according to the literature; 150 Newton (N) force per tooth was applied for occlusal loading, and 100 N force was applied for oblique loading.
When the highest tensile (Pmax) and compressive (Pmin) stresses in the bone under vertical and oblique forces were examined, the highest stress was observed in Model 1, and the lowest was observed in Model 3. The von Mises stress values observed in the metal substructure were the highest in Model 1 and the lowest in Model 3. The von Mises stress in the abutments and implants was highest in Model 3 and lowest in Model 1. When the subperiosteal implant screws were examined, more von Mises stress was observed in the subperiosteal implant screws used in Model 3 than in those used in Model 2. Among the three different treatment options applied in the atrophic maxilla, the highest stress in the bone occurred in the conventional and zygomatic implants, and the lowest stress occurred in the subperiosteal implant with a zygomatic bone anchor.
Different types and designs of implants may be alternatives to advanced surgical methods in the rehabilitation of atrophic maxillary lesions. This study underscores the importance of implant and bone design in choosing optimal anchorage zones, particularly in cases of severe bone loss in the edentulous maxilla. In light of these findings, we recommend implant systems that are specially developed for appropriate rehabilitation in the atrophic edentulous maxilla.
本研究旨在通过有限元分析（FEA）评估无牙萎缩上颌骨在咬合力作用下的应力分布，以比较传统种植体、颧骨种植体和不同设计的骨膜下种植体（SI）。
根据CT扫描重建无牙萎缩上颌骨的三维模型。模拟了三种模型：模型1为带有颧骨和传统种植体；模型2为梨状孔和延伸至颧上颌支柱的骨膜下种植体；模型3为梨状孔和覆盖颧支柱的骨膜下种植体。根据文献赋予力学性能；垂直加载时每颗牙施加150牛顿（N）的力，斜向加载时施加100 N的力。
在垂直和斜向力作用下检查骨内的最高拉应力（Pmax）和压应力（Pmin）时，模型1中的应力最高，模型3中的应力最低。在金属子结构中观察到的冯·米塞斯应力值在模型1中最高，在模型3中最低。基台和种植体中的冯·米塞斯应力在模型3中最高，在模型1中最低。检查骨膜下种植体螺钉时，模型3中使用的骨膜下种植体螺钉比模型2中使用的螺钉观察到更多的冯·米塞斯应力。在萎缩上颌骨应用的三种不同治疗方案中，骨内的最高应力出现在传统种植体和颧骨种植体中，最低应力出现在带有颧骨锚固的骨膜下种植体中。
不同类型和设计的种植体可能是萎缩性上颌骨病变修复中先进手术方法的替代方案。本研究强调了种植体和骨设计在选择最佳锚固区方面的重要性，特别是在无牙上颌骨严重骨丢失的情况下。根据这些发现，我们推荐专门为萎缩性无牙上颌骨的适当修复而开发的种植体系统。
