| Summary: | The aim of this study was to investigate the orthodontic force exerted by thermoplastic orthodontic appliances incorporating <i>Eucommia</i><i>ulmoides</i> in terms of usefulness as the aligner-type orthodontic device. Erkodur, Essix C+<sup>®</sup>, <i>Eucommia</i> elastomer, and edgewise brackets were used (<i>n</i> = 3, each; thickness = 1.0 mm, each). The orthodontic force on the upper right incisor was measured every 24 h for two weeks using a custom-made measuring device. The force of the <i>Eucommia</i> elastomer (4.25 ± 0.274 N) and multi bracket system (5.32 ± 0.338 N) did not change from the beginning to the end (<i>p </i>> 0.01). The orthodontic force exerted by the <i>Eucommia</i> elastomer was lower than that of the multi-bracket orthodontic appliance from the beginning to the end. The force of Erkodur significantly decreased from the beginning to 24 h (6.47 ± 1.40 N) and 48 h (3.30 ± 0.536 N) (<i>p </i>< 0.01). The force of Essix C+<sup>®</sup> significantly decreased from the beginning (13.2 ± 0.845 N) to 24 h (8.77 ± 0.231 N) (<i>p </i>< 0.01). The thermoplastic orthodontic appliance made of <i>Eucommia</i> elastomer continuously exerted a constant orthodontic force for two weeks under water immersion conditions. The orthodontic force of <i>Eucommia</i> elastomer was found to be similar to the orthodontic force exerted by the multi-bracket orthodontic appliance with 0.019 × 0.025 in nickel–titanium wire. These results suggest that the <i>Eucommia</i> elastomer has possibly become one of the more useful materials to form thermoplastic orthodontic appliance exerting low continues orthodontic force.
|
|---|
