Comparative mechanical performance of thermoplastic materials for clear aligners under simulated oral conditions

• 발행기관: 대한치과교정학회
• 저자명: Miao Liu Yajie Wang Ce Bian Yang Han Xuan Qin Jingyao Sun Yuxing Bai Ning Zhang
• 간행물 정보: 『The Korean Journal of Orthodontics』제55권 제5호, 380~391쪽, 전체 12쪽
• 주제분류: 의약학 > 기타의약학
• 파일형태: PDF
• 발행일자: 2025.09.30

국문 초록

Objective: To assess the suitability of polycyclohexylenedimethylene terephthalate glycol (PCTG) for orthodontic aligners and to compare the mechanical properties and 14-day stress relaxation behavior of different materials under simulated oral conditions, offering clinical guidance for material selection. Methods: Materials used were Maxflex, Scheu, and Fusion Align, consisting of thermoplastic polyurethane (TPU), polyethylene terephthalate glycol (PETG), and PCTG, respectively. The following experiments were conducted: (1) tensile testing at 23°C and under simulated oral conditions; (2) prediction of 14-day stress relaxation using the time–temperature superposition principle; (3) right-angle tear strength testing; and (4) Shore D hardness testing. Results: Mechanical properties followed the trend TPU > PETG > PCTG in elastic modulus, yield strength, right-angle tear strength, and Shore D hardness (P < 0.05); PETG > PCTG > TPU in yield strain (P < 0.05). TPU showed higher elongation at break than PETG and PCTG (P < 0.05), with no significant difference between PETG and PCTG (P > 0.05). Stress relaxation behavior was predicted based on the time–temperature superposition principle. With prolonged duration, the stress ranking progressively shifted from TPU > PETG > PCTG to PCTG > PETG > TPU. Conclusions: PCTG exhibits light and sustained force, but its tear resistance and hardness are relatively low. In contrast, TPU demonstrates excellent tear resistance and hardness but experiences rapid force decay.

목차

INTRODUCTION

MATERIALS AND METHODS

RESULTS

DISCUSSION

CONCLUSIONS

REFERENCES

키워드

Aligners Physical property Stress Elastic modulus