Effects on the thickness of single-layer mouthguards with different model positions on the forming table and different sheet frame shapes for the forming device.
model position
mouthguard
sheet frame shape
thermoforming
thickness
Journal
Dental traumatology : official publication of International Association for Dental Traumatology
ISSN: 1600-9657
Titre abrégé: Dent Traumatol
Pays: Denmark
ID NLM: 101091305
Informations de publication
Date de publication:
Feb 2022
Feb 2022
Historique:
revised:
01
06
2021
received:
05
04
2021
accepted:
02
06
2021
pubmed:
2
7
2021
medline:
13
1
2022
entrez:
1
7
2021
Statut:
ppublish
Résumé
Effectiveness and safety of mouthguards are greatly affected by their thickness. The aim of this study was to clarify the influence of the frame shape of the forming device on how the model position on the forming table affects the anterior and posterior mouthguard thickness. Mouthguards were thermoformed using 4.0-mm-thick ethylene-vinyl-acetate sheets and a vacuum forming device. Square sheets were fixed with the square frame of the forming device. Circular sheets were fixed to the forming device with a circular frame. The model was placed with its anterior rim positioned 40, 30, 20, or 10 mm from the front of the forming table. The model position was marked on the forming table so that it was constant under each condition. Six mouthguards were fabricated for each condition. Mouthguard thicknesses of the incisal edge, labial and buccal surfaces, and the cusp were measured. Differences in the rate of thickness reduction due to frame shapes and model positions were analyzed by two-way ANOVA. Difference in the thickness reduction rate depending on the frame shape was observed on the labial and buccal surfaces, and it was significantly greater with the circular frame than with the square frame (p < .01). In the anterior region, the thickness reduction rate tended to increase as the model position was moved toward the front of the forming table. The thickness reduction rate of the posterior portion was lowest when the model's molar was positioned at the center of the forming table. The labial thickness of the mouthguard was not affected by the frame shape if the distance from the model to the frame was larger than the model height. However, the buccal thickness was thinner with the circular frame than with the square frame regardless of the model position.
Sections du résumé
BACKGROUND/AIM
OBJECTIVE
Effectiveness and safety of mouthguards are greatly affected by their thickness. The aim of this study was to clarify the influence of the frame shape of the forming device on how the model position on the forming table affects the anterior and posterior mouthguard thickness.
MATERIALS AND METHODS
METHODS
Mouthguards were thermoformed using 4.0-mm-thick ethylene-vinyl-acetate sheets and a vacuum forming device. Square sheets were fixed with the square frame of the forming device. Circular sheets were fixed to the forming device with a circular frame. The model was placed with its anterior rim positioned 40, 30, 20, or 10 mm from the front of the forming table. The model position was marked on the forming table so that it was constant under each condition. Six mouthguards were fabricated for each condition. Mouthguard thicknesses of the incisal edge, labial and buccal surfaces, and the cusp were measured. Differences in the rate of thickness reduction due to frame shapes and model positions were analyzed by two-way ANOVA.
RESULTS
RESULTS
Difference in the thickness reduction rate depending on the frame shape was observed on the labial and buccal surfaces, and it was significantly greater with the circular frame than with the square frame (p < .01). In the anterior region, the thickness reduction rate tended to increase as the model position was moved toward the front of the forming table. The thickness reduction rate of the posterior portion was lowest when the model's molar was positioned at the center of the forming table.
CONCLUSIONS
CONCLUSIONS
The labial thickness of the mouthguard was not affected by the frame shape if the distance from the model to the frame was larger than the model height. However, the buccal thickness was thinner with the circular frame than with the square frame regardless of the model position.
Types de publication
Journal Article
Langues
eng
Pagination
88-94Subventions
Organisme : Nippon Dental University Intramural Research Fund
Informations de copyright
© 2021 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
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