Vacuum-formed mouthguard fabrication to obtain proper fit using notched sheet

Mouthguards should be provided with appropriate thickness and proper fit to exert their effects. However, mouthguard thickness becomes thinner after forming. The aim of this study was to examine the effect of using a notched mouthguard sheet and forming as the heated surface of the sheet contacts the surface of the working model.

The material used was a 3.8-mm-thick Sports Mouthguard. Notches with a length of 90 and 80 mm were cut into an ethylene vinyl acetate sheet 20 mm from the anterior and posterior margins and 15 mm from the right and left margins, respectively, and the sheet was compared with the original. The sheets were then formed using a vacuum former. Original and notched sheets were heated until the temperature of the sheet reached 80°C, and the non-heated surface of the sheet was sucked down over the model. Both sheets were also heated at first until the sheet temperature reached 80°C, then turned upside down, and the heated surface of the sheet was sucked down over the model. The thickness and fit of the mouthguard were measured at the central incisor and first molar. Differences in thickness and fit according to the measurement parts and the sheet conditions were analyzed by two-way ANOVA.

The thickness of the mouthguard significantly differed by the measurement parts and the sheet conditions (P < 0.01), and the notched sheet maintained the required thickness. Fit differed between the measurement parts and the sheet conditions (P < 0.01), and the sheets formed as the heated surface contacted the working model showed better fit.

These results suggest that the ideal mouthguard with appropriate thickness and proper fit can be fabricated by notching a sheet and contacting the heated surface of the sheet to the working model.