Silva Lorena S, Verri Fellippo R, Lemos Cleidiel A A, Martins Christine M, Pellizzer Eduardo P, de Souza Batista Victor E
Graduate student, Department of Prosthodontics, Presidente Prudente Dental School, University of Western São Paulo - UNOESTE, Presidente Prudente, Brazil.
Associate Professor, Department of Dental Materials and Prosthodontics, Araçatuba Dental School (UNESP), Univ Estadual Paulista, Araçatuba, Brazil.
J Prosthet Dent. 2021 Aug;126(2):223.e1-223.e8. doi: 10.1016/j.prosdent.2021.04.024. Epub 2021 Jun 5.
Whether providing an occlusal device for a patient with bruxism and an implant-supported fixed dental prosthesis leads to improved biomechanics is unclear.
The purpose of this 3D finite element analysis (FEA) study was to evaluate the biomechanical behavior of 3-unit implant-supported prostheses under parafunctional forces with and without an occlusal device.
Eight 3D models consisting of a posterior (type IV) maxillary bone block with 3 external hexagon implants (Ø4.0×7.0 mm) and 3-unit implant-supported prostheses with different crown connections (splinted or unsplinted) and an occlusal device under functional and parafunctional loading were simulated. The abutment screws were evaluated by von Mises stress maps, and the bone tissue by maximum principal stress and microstrain maps by using a finite element software program.
An occlusal device improved the biomechanical behavior of the prostheses by reducing stress in the abutment screws and stress and strain in the bone tissue. However, the use of an occlusal device was not sufficiently effective to negate the biomechanical benefit of splinting.
The use of splinted crowns in the posterior maxillary region with an occlusal device was the most effective method of reducing stress in the abutment screws and stress and strain in the bone tissue when parafunction was modeled.
对于磨牙症患者和种植体支持的固定义齿，提供咬合装置是否能改善生物力学尚不清楚。
本三维有限元分析（FEA）研究的目的是评估在有和没有咬合装置的情况下，3单位种植体支持的修复体在副功能力作用下的生物力学行为。
模拟了8个三维模型，包括一个带有3个外六角种植体（Ø4.0×7.0 mm）的上颌后牙区（IV型）骨块、具有不同冠连接方式（联冠或非联冠）的3单位种植体支持的修复体以及在功能和副功能负荷下的咬合装置。通过使用有限元软件程序，根据冯·米塞斯应力图评估基台螺钉，根据最大主应力和微应变图评估骨组织。
咬合装置通过降低基台螺钉中的应力以及骨组织中的应力和应变，改善了修复体的生物力学行为。然而，使用咬合装置并不足以有效消除联冠的生物力学益处。
当模拟副功能时，在上颌后牙区使用联冠并配合咬合装置是降低基台螺钉应力以及骨组织应力和应变的最有效方法。
