Influence of mouthguards and their palatal design on the stress-state of tooth-periodontal ligament-bone complex under static loading.

BACKGROUND/AIM: The mouthguard (MG) is an effective device to reduce the risk of dental traumatic injuries, but the mechanical effects of wearing a MG and its design are not fully understood. The aim of this study was to evaluate the mechanical influence of wearing a MG and its palatal design on the tooth-periodontal ligament-bone complex (TPBC) by computational analysis using the finite element method.

MATERIAL AND METHODS: Three-dimensional subject-specific geometry of the TPBC was reconstructed from medical computed tomography (CT) images. Two patterns of MG geometries were constructed which covered the palatal domain or not (the position of these palatal margins was set at -8 mm (pattern 1) and 4 mm (pattern 2) from the cervical line. Five cases of static mechanical analysis were conducted by changing the location of the loading points from near the cervical line to the tip of the tooth.

RESULTS: Wearing a MG decreased strain concentration around the loading point and cervical domain regardless of the MG palatal design. Elastic energy in the periodontal ligament (PDL) and tooth (including enamel and dentin) decreased when the MG was worn, whereas the MG palatal design slightly affected the degree of reduction in the elastic energies. The location of the loading points remarkably affected the elastic energy in the TPBC components and the extent of its reduction due to the MG.

CONCLUSIONS: These findings indicated that the protection ability of the MG exerted in the restricted situations of traumatic events occurs regardless of the MG design.