Related Experiment Video
Updated: Jan 2, 2026

Artificial Thermal Ageing of Polyester Reinforced and Polyvinyl Chloride Coated Technical Fabric
Published on: January 29, 2020
Influence of constant strain on the elasticity of thermoplastic orthodontic materials
Sayuri Inoue1,2, Satoshi Yamaguchi1, Hiroshi Uyama3
1Department of Biomaterials Science, Osaka University Graduate School of Dentistry.
Abstract:
The aim of this study was to identify a physical property suitable for evaluating the orthodontic force by analyzing the physical properties of thermoplastic materials. Four thermoplastic materials were used: Essix A+® Plastic (EA), DURAN® (DU), Erkodur (ER), and Essix C+® Plastic (EC). Finite element analysis (FEA), a water absorption test, constant strain loading test, X-ray diffraction (XRD) and Fourier transformation infrared spectroscopy analysis were conducted. FEA found a significant correlation between the elastic modulus and the orthodontic force. The water absorption of EC was significantly smaller than the other materials. EC showed no elastic modulus change. The XRD pattern indicated that EC was a crystalline polymer. FEA of thermoplastics showed that the elastic modulus is suitable for the evaluation of orthodontic force. The crystalline thermoplastic EC demonstrated a stable elastic modulus even under strain in a wet environment, suggesting the advantage of its use as an orthodontic aligner material.
Related Concept Videos
Plastic Behavior
Thermal Strain
Hooke's Law
Relation between Poisson's ratio, Modulus of Elasticity and Modulus of Rigidity
Members Made of Elastoplastic Material
As the bending moment...
Stress-Strain Diagram - Ductile Materials

