Comparison of the physical characteristics of six commonly used plates in clear aligner therapy

Objectives The study evaluated six commonly used thermoplastic materials for clear aligner therapy, focusing on their mechanical properties to identify suitable options for patient treatment. Materials and Methods Bioart 0.75, Erkodur_al 0.8, Monoflex 0.8, Duran 0.625, Duran 0.75, and CA Pro 0.75 were selected. The three-point-bending tests in a range of 2.5 mm displacement under non-thermoformed, thermoformed, after 20 hours, and after 7 days of loaded conditions immersed in water performed. Water absorption and FTIR-ATR spectroscopy for chemical evaluation were measured. Plate thickness was assessed before and after thermoforming. Statistical analyses were performed using descriptive statistics, one-way ANOVA and Tukey-Kramer multiple comparison tests. Results FTIR-ATR analyses revealed similar spectral profiles for all materials. Monoflex exhibited the greatest variation in thickness post-thermoforming. Water absorption increased after thermoforming and immersion. Erkodur_al showed higher absorption at 20 hours and Duran 0.75 at 7 days. CA Pro 0.75 demonstrated superior long-term stability in elastic modulus and force compared to other aligners, while Duran 0.75 maintained greater force after 20 hours and 7 days at 0.25 mm displacement. Conclusions The mechanical characteristics of thermoforming plates and the type of tooth movement are essential for selecting the right plastic material. CA Pro 0.75, with its lower force deflection rate and reduced elastic modulus, is ideal for reducing the number of aligners and increasing patient comfort. Clinical Relevance By evaluating the physical properties of the plates, clinicians can select the most suitable plate for specific treatment objectives.