Postgraduate, Department of Restorative Dentistry, School of Dentistry, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
Adjunct Professor, Department of Restorative Dentistry, School of Dentistry, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
Implant Dent. 2018 Jun;27(3):294-302. doi: 10.1097/ID.0000000000000737.
Biomechanical behavior of tooth-implant-supported prostheses (TISPs) with external and internal implants was compared.
Two 3-D models of TISP were designed by varying the implant: external (Model EH) and internal hexagons (Model IH). After loading, von Mises stresses were obtained in implants, abutments, and screws. Principal maximum (σmax) and minimum (σmin) stresses were analyzed in periodontal ligament (PL), alveolar bone, and periimplant bone.
Model IH showed lower stress peaks in axial loading in the implant and in the screw but higher in abutment. In oblique loading, Model IH had lower stresses in the implant, but higher in the abutment and in the screw. In the σmax analysis for axial and oblique loads, stress peaks in Model IH were lower in PL, alveolar bone, and periimplant bone. In the σmin analysis for axial load, stress peaks in Model IH were lower in PL, but higher in alveolar bone and in periimplant bone. In oblique load, Model IH showed lower stress peaks in PL and alveolar bone, but higher stress peaks in periimplant bone.
TISPs with IH implants do present lower risk of biomechanical failure.
比较外植体和内植体支持的牙种植体修复体（TISPs）的生物力学行为。
通过改变植入物设计了两种 TISP 的 3D 模型：外六角（EH 模型）和内六角（IH 模型）。加载后，在种植体、基台和螺钉中获得了冯·米塞斯应力。分析了牙周膜（PL）、牙槽骨和种植体周围骨中的主最大（σmax）和最小（σmin）应力。
轴向加载时，EH 模型的种植体和螺钉中的应力峰值较低，但基台中的应力峰值较高。在斜向加载时，EH 模型的种植体中的应力峰值较低，但基台和螺钉中的应力峰值较高。轴向和斜向加载时的σmax 分析中，EH 模型的 PL、牙槽骨和种植体周围骨中的应力峰值较低。轴向加载时的σmin 分析中，EH 模型的 PL 中的应力峰值较低，但牙槽骨和种植体周围骨中的应力峰值较高。斜向加载时，EH 模型的 PL 和牙槽骨中的应力峰值较低，但种植体周围骨中的应力峰值较高。
具有 IH 植入物的 TISPs 确实具有较低的生物力学失败风险。
