Comparison of Shock Absorption Capacities of 3D-Printed Custom-Made Mouthguards: A Comparative In Vitro Study

Area of Science:

• Biomaterials Engineering
• Sports Medicine
• Additive Manufacturing

Background:

• New resins for 3D-printed mouthguards are available for contact sports.
• No studies have assessed the impact performance of these novel materials.
• This study aimed to compare shock absorption of 3D-printed vs. thermoformed mouthguards.

Purpose of the Study:

• To evaluate and compare the impact performance and shock absorption capacities of custom-made mouthguards fabricated using additive manufacturing (3D printing) versus traditional thermoforming.
• To assess the mechanical performance of different mouthguard materials under repeated impact conditions.

Main Methods:

• Fabrication of three types of custom mouthguards: 3D-printed (Keyguard, Dima resin) and thermoformed triple-layer.
• Impact testing according to the NF S72-427 standard for industrial mouthguards, measuring transmitted force and deceleration.
• Evaluation of mechanical performance through five consecutive impacts and assessment of thickness decrease via 3D scanning.

Main Results:

• None of the tested mouthguards met the NF S72-427 impact absorption standard.
• Thermoformed mouthguards failed structurally after the first impact.
• 3D-printed mouthguards showed average peak decelerations between 255-299g and transmitted forces of 2753-3292N, with minimal thickness decrease (0.1-0.2mm).

Conclusions:

• Despite not meeting the standard, 3D-printed mouthguards demonstrated superior, repeatable shock absorption compared to thermoformed ones.
• Additive manufacturing presents a potentially cost-effective and viable alternative for producing custom mouthguards, especially for athletes needing frequent replacements.
• Further research and potential standard revisions are warranted to optimize 3D-printed mouthguards for sports protection.