Introduction Athletes of contact sports are prone to cranial, orofacial and dental injuries in case of a traumatic head impact. Mouthguards can be potentially beneficial in reducing the injury risk by changing the dynamics of an impact to teeth. Indeed, dissipative capacity of mouthguard materials influences the extent of transferred force. However, the effect of geometrical/structural attributes should not be neglected on the mouthguards performance.

Objective The aim of this study is to evaluate the role of different design variables in protective capability of mouthguards and to find an optimal configuration by means of computer aided engineering.

Design and Setting A detail anatomical human upper jaw model was developed including teeth, periodontal ligament and maxilla bone. The incisor impact with an ice hockey puck was then simulated by finite element analysis with and without mouthguard. Various mouthguard configurations were designed by employing different material properties, laminated composite arrangement, layers thickness, and space inclusion.

Main Outcome Measurements The maximum effective stress on the incisors, contact force profile and stress distribution were compared to evaluate effect of different parameters on mouthguard protective performance.

Results While larger thickness always reduces the risk of injury in all configurations, the effectiveness of space inclusion and composite layers arrangement are design dependent. The optimal configuration was obtained when we combined graded stiffness layers (2000 to 20 Mpa) arrangement with a predefined gap (1 mm) in front of incisors. In this specific design, limiting the mouthguard thickness to 3 mm resulted in acceptable protective performance compared to 4 mm case and was preferred for the sake of athletes comfort.

Conclusion Both structural and material properties are playing a key role in shock absorbing capabilities of mouthguard. There is a need to practice multi-materials 3D printing for fabrication of customized mouthguards to maximize their performance and comfort.