Related Experiment Video
Updated: Jan 16, 2026
Shape Memory Polymers for Active Cell Culture
Published on: July 4, 2011
Effect of varying thicknesses and temperature changes on shape memory behaviour in 3D DPA versus thermoformed clear
Venkata Durga Mahendra Tivanani1, Swetha Reddy Dalli1, Praveen Kumar Varma Datla1
1Department of Orthodontics and Dentofacial orthopedics, Vishnu Dental College, Bhimavaram, Andhra Pradesh, India.
Background:
The present study evaluated the shape memory behaviour of TA-28 compared to PET-G at different thicknesses and temperatures.
Methods:
Two materials were tested: thermoformed CA Pro (PET-G) and 3D-printed TA-28 (Graphy, Korea), in 0.5mm and 0.75mm thicknesses. A total of 160 aligner strips were fabricated and tested for shape recovery at 30°C, 37°C, 40°C, and 80°C. Each strip was bent at 100°C and recovery was measured over 60minutes using a protractor-based template.
Results:
TA-28 exhibited significantly higher shape recovery than PET-G at all temperatures (P≤0.001). Recovery increased with temperature and was greatest for the 0.5mm TA-28 samples. At 37°C, TA-28 reached up to 60.7% recovery within 60minutes, while PET-G showed negligible change. Three-way ANOVA revealed significant interactions among material, thickness, and temperature (P=0.005).
Conclusion:
TA-28 aligners demonstrate superior shape memory properties compared to PET-G, particularly at body temperature. TA-28 samples with 0.5mm thickness recovered faster and to a greater extent, offering more consistent force delivery.
Clinical Significance:
Directly 3D-printed TA-28 aligners may enhance treatment predictability, reduce patient discomfort, and provide sustained orthodontic force due to their temperature-responsive shape recovery. These findings support the use of smart materials in future orthodontic aligner design.
Related Concept Videos
01:19Thermal Strain
01:21Plastic Behavior