Finite Element Analysis of Dentoalveolar Stress in Combat Sports Using Hybrid and Conventional Mouthguards

This study aimed to contribute to the development of modern mouthguards by evaluating the stresses generated by hook and uppercut punches applied during combat sports on dentoalveolar structures and mouthguards, the protective effectiveness of different mouthguard designs, and the resulting deformations using three-dimensional finite element analysis.

Three-dimensional solid models of the maxilla, mandible, teeth, alveolar bone, and mouthguards were constructed using an anatomical head model with Class I occlusion and complete permanent dentition. A conventional mouthguard with a uniform thickness of 4 mm made of ethylene vinyl acetate and a hybrid mouthguard consisting of a 3 mm polycarbonate occlusal surface with EVA axial walls were modeled. Hook and uppercut punch loads were simulated at an impact velocity of 12 m/s with an effective mass parameter of 5 kg. Von Mises equivalent stresses and displacement values occurring in the jaws, teeth, alveolar structures, and mouthguards were analyzed using three-dimensional finite element analysis.

During hook and uppercut punch application, the highest von Mises stress values in the mandible were observed in the model without a mouthguard (200 and 520 MPa, respectively), while the lowest values were detected in the model with a hybrid mouthguard (170 and 260 MPa). Similarly, mandibular teeth exhibited the highest stress values in the model without a mouthguard (1100 and 1600 MPa) and the lowest values in the hybrid mouthguard model (300 and 500 MPa). Stress transmission to the maxilla and maxillary teeth was minimal in all models. For both punch types, the hybrid mouthguard demonstrated higher stress values than the conventional mouthguard. In models using mouthguards, maximum displacement occurred later after impact, and deformation was distributed over a wider surface area rather than being localized.

Hybrid mouthguards demonstrated superior biomechanical performance compared with conventional mouthguards by reducing stress transmission to dentoalveolar structures. The combination of a rigid occlusal component and flexible axial walls enabled more effective energy distribution, particularly under high-energy vertical loading. These findings suggest that hybrid mouthguards represent an effective option for preventing dentoalveolar trauma in combat sports.