Biomechanical Analysis of a Custom-Made Mouthguard Reinforced With Different Elastic Modulus Laminates During a Simulated Maxillofacial Trauma

Abstract

Background/Aims: There is a lack of data regarding the influence of different laminates for mouthguard reinforcement in the mechanical response during an impact in the orofacial region. The aim of this study was to verify the influence of the laminate framework on the stresses and strains of the anterior teeth and displacement of ethylene-vinyl acetate (EVA) custom-made mouthguards during a simulated impact. The null hypotheses was that the different laminates reinforcement would present the similar effect in maxillary structures, regardless the elastic modulus. Methods: A finite element model of human maxillary central incisors with an antagonist contact was used. A linear quasi-static analysis was used to simulate the force exerted during an impact. A total of 5 different layers were simulated inside the mouthguard at the labial portion according to the Elastic Modulus 1 MPa (Extremely flexible), 9 GPa (Low modulus reinforcement), 18 GPa (Without reinforcement), 50 GPa (Flexible alloy), 100 GPa (Titanium alloy) and 200 GPa (Hard material). The results were evaluated by means of Maximum Principal Stress (in the tooth and bone), Microstrain (periodontal ligament) and Displacement (mouthguard) criteria. Results: The elastic modulus of the material inside the MG influenced the stress distribution on the enamel buccal face. However, it did not affect the bone tissue stress, periodontal ligament strain or root dentin tissue stress. Conclusion: The use of reinforcement inside the custom-made mouthguard can modify the stress generated in the enamel buccal surface without improvement to the root dentin, periodontal ligament or bone tissue.

The Effectiveness of Dental Protection and the Material Arrangement in Custom-Made Mouthguards

“…For the bone tissue, the stress concentration area was at the crestal level of the alveolar bone in the buccal side, regardless of the design or material used in the mouthguard. Some of the published finite element studies do show a different critical area in the maxilla bone [16]. This behavior can be justified with the presence or not of the periodontal ligament (PDL).…”

“…Regarding this design variable, the experimental works of Westerman et al [14] and Takeda et al [15] indicate that the inclusion of one air layer in the mouthguard material improves the characteristic impact of mouthguards. At the same time, the numerical study of Tribst et al [16] reported some behavior differences. The authors reported that the material's elastic modulus inside the MG influenced the stress distribution on the buccal surface of enamel.…”

“…Still, in terms of energy absorption and transmission of forces, 4 mm seems to be the ideal thickness. The material arrangement within the mouthguard design has gained attention from some researchers [14][15][16].…”

Biomechanical Behavior Evaluation of a Novel Hybrid Occlusal Splint-Mouthguard for Contact Sports: 3D-FEA

“…The positive effects of a mouthguard to prevent tooth injury have been already reported in the literature using three-dimensional [ 3 , 4 , 6 ] and bi-dimensional finite element analyses [ 16 , 30 ]. There is a consensus about the stress magnitude reduction for dentin, enamel [ 3 , 6 , 16 ], and bone tissue [ 3 , 4 , 7 ] at the impact momentum when the mouthguard is in position. This study’s simulation corroborates the previous literature, indicating a stress magnitude decrease associated with the use of the novel hybrid occlusal splint-sportguard (HGM).…”

“…During a traumatic contact sport impact, the most suitable material to be used in mouthguards to protect the orofacial structures should be the flexible polymers, which distribute the stress concentration [ 15 , 16 ]. Coincidentally, rigid occlusal stabilization splints are considered an ideal option, as compared to soft occlusal splints, for patients with bruxism.…”