Evaluación in vitro de la resistencia al impacto de protectores bucales utilizados en deportes de contacto amateur.

Abstract

Objective: To evaluate and compare in vitro the impact resistance of custom and thermoformable mouthguards used in amateur contact sports, considering thickness and number of layers. Materials and methods: A comparative in vitro experimental study was conducted with 32 specimens distributed into four groups (n = 8): single-layer custom mouthguards (1.5 mm), double-layer custom mouthguards (2.5 mm), single-layer thermoformable mouthguards, and double-layer thermoformable mouthguards. Tests were performed using a dart impact machine with a standardized drop height of 0.44 m, applying progressive mass increments until one or more teeth of the artificial maxillary model fractured. The load at the moment of failure and the corresponding energy, calculated using the gravitational potential energy equation, were recorded. Statistical analysis included normality tests (Shapiro-Wilk) and comparisons between groups using the Kruskal-Wallis test with Bonferroni correction. Results: Statistically significant differences were observed between the groups (p < 0.05). Custom double-layer protectors exhibited the highest energy values at failure, followed by custom single-layer protectors, while thermoformable protectors showed lower values. Conclusion: The manufacturing method, thickness, and number of layers significantly influence impact resistance, with custom multi-layer protectors demonstrating better mechanical performance under controlled experimental conditions.