Thickness of Mouthguard Sheet after Formation Based on the Shape of the Mouthguard Sheet

Purpose: The usefulness of mouthguard to prevent stomatognathic injury during sports depends on the materials and the thickness of the mouthguard. The aim of this study was to investigate the thickness of mouthguard sheet after vacuum forming based on the shape of the mouthguard sheet during heating conditions. Methods: Cross stripes (10×10 mm) were printed in mouthguard sheets. The thickness of each cross stripe area was measured by measuring device. The plaster cast was trimmed to the height of 20 mm at the incisal edge of the upper central incisor and 15 mm at the medial buccal cusp of the upper fi rst molar. The sheets were heated until they sagged 10, 15, and 20 mm from baseline by vacuum former. Two shapes of the sheet were compared as follow: Impactguard grooved sheet (IM-G) and flat sheet (IM-F). The difference in the ratio of change of thickness depending on the shapes of the sheet and the heating conditions was analyzed by two-factor ANOVA. Results: The change of thickness in the part of the sheet fi tted to the anterior teeth and posterior teeth of IM-G was smaller than that of IM-F. The change of thickness was infl uenced by the heating conditions. Conclusions: This study suggests that the thickness of mouthguard sheet after vacuum forming was affected by the shape of the sheet, and the grooved sheet could secure the thickness in the part of the anterior teeth and posterior teeth of mouthguard sheet.