Department of Oral Rehabilitation, Federal University of Goiás, Goiânia, Brazil.
Faculdade de Odontologia, Faculdades de Ciências Odontológicas, FCO, Montes Claros, Montes Claros, Brazil.
Dent Traumatol. 2022 Oct;38(5):431-438. doi: 10.1111/edt.12746. Epub 2022 Mar 12.
BACKGROUND/AIM: The use of custom-fitted mouthguards can effectively prevent dentoalveolar trauma during sports practice. The aims of this study were to (1) Evaluate the elastic modulus of different EVA commercial brands used for custom-fitted mouthguards, and (2) Evaluate whether the different EVA brands can influence the stress and strain generated during an impact simulated by three-dimensional finite element analysis.
The elastic modulus of five EVA commercial brands (Essence , Bio-Art , Proform , PolyShok , and Erkodent ) were calculated through uniaxial tensile tests. The obtained values were evaluated statistically by Kruskal-Wallis and Dunn's test. A three-dimensional model of the anterior maxilla was created using the Rhinoceros 5.0. A 3 mm custom-fitted mouthguard was simulated. The three-dimensional volumetric mesh was generated using the Patran software (MSC.Software) with isoparametrics, 4-noded tetrahedral elements, and exported to Marc/Mentat (MSC.Software) as element number 134. A non-linear dynamic impact analysis was performed in which a rigid object struck the central incisor at a speed of 5 m/s. The stresses were evaluated by the modified von Mises criteria, and the strains were also recorded.
Statistically significant differences were observed for elastic modulus values (p < .001). Median values and the results of the Dunn's test were Essence (38.1 A), Bio-Art (34.9 AB), Proform (20.8 BC), PolyShok (17.4 CD), and Erkodent (15.0 D) (different capital letters mean statistical differences among the groups). Stresses and strains generated in the model with mouthguards were significantly lower than the model without a mouthguard regardless of the commercial brand. There was no significant difference in the stress and strain on the enamel and dentin with the different EVA brands. The shock absorption ability was high for all the brands (more than 80%).
The custom-fitted mouthguards, independently of the commercial brand, reduced stresses and strains during the impact.
背景/目的：定制式口腔防护器可有效预防运动中发生的牙牙槽外伤。本研究旨在：(1)评估用于定制式口腔防护器的五种不同 EVA 商业品牌的弹性模量；(2)通过三维有限元分析评估不同 EVA 品牌是否会影响冲击过程中产生的应力和应变。
通过单轴拉伸试验计算五种 EVA 商业品牌（Essence、Bio-Art、Proform、PolyShok 和 Erkodent）的弹性模量。通过 Kruskal-Wallis 和 Dunn 检验对获得的值进行统计学评估。使用 Rhinoceros 5.0 创建前上颌的三维模型。模拟 3mm 定制式口腔防护器。Patran 软件（MSC.Software）生成三维体积网格，采用等参、4 节点四面体单元，然后以元素编号 134 输出到 Marc/Mentat（MSC.Software）。以 5m/s 的速度使刚性物体撞击中切牙进行非线性动态冲击分析。通过修正的 von Mises 准则评估应力，同时记录应变。
弹性模量值存在统计学显著差异（p<0.001）。中位数和 Dunn 检验结果为：Essence（38.1A）、Bio-Art（34.9AB）、Proform（20.8BC）、PolyShok（17.4CD）和 Erkodent（15.0D）（不同大写字母表示组间存在统计学差异）。无论使用何种商业品牌，有和无口腔防护器的模型中产生的应力和应变均显著降低。不同 EVA 品牌的牙釉质和牙本质的应力和应变无显著差异。所有品牌的减震能力均较高（>80%）。
无论商业品牌如何，定制式口腔防护器均可降低冲击过程中的应力和应变。
