Physical properties of thermoplastic material for clear aligners

Cha,  Jung-Yul

doi:2016.54.7.542

J Korean Dent Assoc > Volume 54(7); 2016 > Article

The Journal of The Korean Dental Association 2016;54(7):542-550.
DOI: https://doi.org/10.22974/jkda.2016.54.7.006 Published online July 31, 2016.

투명 장치의 열가소성 재료의 올바른 이해

차정열

연세대학교 치과대학 치과교정학교실

Physical properties of thermoplastic material for clear aligners

Jung-Yul Cha

Department of Orthodontics, College of Dentistry, Institute of Craniofacial deformities, Yonsei University

Abstract

Recent technological advance have greatly expanded the application of invisible orthodontic treatment using clear thermoplastic materials. However, the final outcomes using clear aligner system do not achieve the level of final goal frequently, which results in case refinement, midcourse correction, or fixed orthodontic treatment. Therefore, mechanical properties of thermoplastic materials should be considered to improve the quality of outcomes. The purposes of this special article were to evaluate the force and stress depending on the materials, deflection and thickness of thermoplastic materials and to evaluate the mechanical properties of thermoplastic materials after repeated loading. Thickness and amount of deflection rather than products and materials showed the largest effect on force and stress. In all products, at least 159 gf of force was required for more than 1.0 mm deflection or when materials with 1.0 mm thickness were deflected. Orthodontic forces delivered by thermoplastic materials depend on the materials, thickness, amount of activation, and intra-oral condition. Proper thickness of thermoplastic materials and deflection level of tooth movement should be decided for the efficient and physiologic tooth movement.

Key Words: thermoplastic materials;clear aligner;tooth movement;