Borges Alexandre Luiz Souto, Dal Piva Amanda Maria de Oliveira, Concílio Laís Regiane da Silva, Paes-Junior Tarcisio José de Arruda, Tribst João Paulo Mendes
Institute of Science and Technology, São Paulo State University (Unesp), São José dos Campos, São Paulo 12220690, Brazil.
Department of Prosthodontics, School of Dentistry, University of Taubaté, Taubaté, São Paulo 12020-340, Brazil.
Life (Basel). 2020 Nov 20;10(11):294. doi: 10.3390/life10110294.
(1) Background: Trauma is a very common experience in contact sports; however, there is an absence of data regarding the effect of athletes wearing mouthguards (MG) associated with ankylosed maxillary central incisor during a traumatic impact. (2) Methods: To evaluate the stress distribution in the bone and teeth in this situation, models of maxillary central incisor were created containing cortical bone, trabecular bone, soft tissue, root dentin, enamel, periodontal ligament, and antagonist teeth were modeled. One model received a MG with 4-mm thickness. Both models were subdivided into finite elements. The frictionless contacts were used and a nonlinear dynamic impact analysis was performed in which a rigid object hit the model at 1 m·s. For each model, an ankylosed periodontal ligament was simulated totaling 4 different situations. The results were presented in von-Mises stress maps. (3) Results: A higher stress concentration in teeth and bone was observed for the model without a MG and with ankylosed tooth (19.5 and 37.3 MPa, respectively); the most promising mechanical response was calculated for patients with healthy periodontal ligament and MG in position (1.8 and 7.8 MPa, respectively). (4) Conclusions: The MG's use is beneficial for healthy and ankylosed teeth, since it acts by dampening the generated stresses in bone, dentin, enamel and periodontal ligament. However, patients with ankylosed tooth are more prone to root fracture even when the MG is in position compared to a healthy tooth.
(1) 背景：创伤在接触性运动中是非常常见的经历；然而，关于运动员佩戴护齿器（MG）与上颌中切牙粘连在创伤性撞击期间的影响，目前缺乏相关数据。(2) 方法：为了评估这种情况下骨骼和牙齿中的应力分布，创建了包含皮质骨、松质骨、软组织、牙根牙本质、牙釉质、牙周韧带的上颌中切牙模型，并对拮抗牙进行了建模。一个模型使用了厚度为4毫米的护齿器。两个模型都被细分为有限元。采用无摩擦接触，并进行了非线性动态冲击分析，其中一个刚性物体以1米/秒的速度撞击模型。对于每个模型，模拟了牙周韧带粘连的情况，共4种不同情形。结果以冯·米塞斯应力图呈现。(3) 结果：未佩戴护齿器且牙齿粘连的模型在牙齿和骨骼中观察到更高的应力集中（分别为19.5和37.3兆帕）；对于牙周韧带健康且佩戴护齿器的患者，计算出的最有利力学响应（分别为1.8和7.8兆帕）。(4) 结论：使用护齿器对健康牙齿和粘连牙齿有益，因为它通过减轻骨骼、牙本质、牙釉质和牙周韧带中产生的应力起作用。然而，与健康牙齿相比，即使佩戴了护齿器，牙齿粘连的患者仍更容易发生牙根骨折。
