Alves Júlio César de Carvalho, Borges Gilberto Antônio, Versluis Antheunis, Soares Carlos José, Veríssimo Crisnicaw
Department of Restorative Dentistry, School of Dentistry, UNIUBE - Universidade de Uberaba, Uberaba, MG, Brazil.
Department of Bioscience Research, College of Dentistry, University of Tennessee Health Science Center, Memphis, TN, USA.
Braz Dent J. 2020 Sep-Oct;31(5):540-547. doi: 10.1590/0103-6440202002818.
The aim of this study was to analyze the influence of orthodontic bracket type (metallic or ceramic) and mouthguard on biomechanical response during impact. Two-dimensional plane-strain models of a patient with increased positive overjet of the maxillary central incisor was created based on a CT scan, simulating the periodontal ligament, bone support, gingival tissue, orthodontic brackets (metallic or ceramic) and mouthguard. A nonlinear dynamic impact finite element analysis was performed in which a steel object hit the model at 1 m/s. Stress distributions (Von Mises and Modified Von Mises) and strain were evaluated. Stress distributions were affected by the bracket presence and type. Models with metallic and ceramic bracket had higher stresses over a larger buccal enamel impact area. Models with ceramic brackets generated higher stresses than the metallic brackets. Mouthguards reduced the stress and strain values regardless of bracket type. Mouthguard shock absorption were 88.37% and 89.27% for the metallic and ceramic bracket, respectively. Orthodontic bracket presence and type influenced the stress and strain generated during an impact. Ceramic brackets generated higher stresses than metallic brackets. Mouthguards substantially reduced impact stress and strain peaks, regardless of bracket type.
本研究的目的是分析正畸托槽类型（金属或陶瓷）和护齿器对撞击过程中生物力学响应的影响。基于CT扫描创建了上颌中切牙正覆盖增加患者的二维平面应变模型，模拟了牙周膜、骨支持、牙龈组织、正畸托槽（金属或陶瓷）和护齿器。进行了非线性动态撞击有限元分析，其中一个钢质物体以1 m/s的速度撞击模型。评估了应力分布（冯·米塞斯应力和修正冯·米塞斯应力）和应变。应力分布受托槽的存在和类型影响。带有金属和陶瓷托槽的模型在更大的颊侧釉质撞击区域具有更高的应力。带有陶瓷托槽的模型产生的应力高于金属托槽。无论托槽类型如何，护齿器都降低了应力和应变值。金属和陶瓷托槽的护齿器减震率分别为88.37%和89.27%。正畸托槽的存在和类型影响撞击过程中产生的应力和应变。陶瓷托槽产生的应力高于金属托槽。无论托槽类型如何，护齿器都能大幅降低撞击应力和应变峰值。
