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Updated: May 24, 2025

Author Spotlight: 3D Movement Assessment of Maxillary Posterior Teeth in Clear Aligner Treatment
Published on: February 23, 2024
An analysis of initial force and moment delivery of different aligner materials
Thomas Wendl1, Brigitte Wendl2, Peter Proff1
1Department of Orthodontics, 9147 University of Regensburg , Regensburg, Germany.
Objectives:
The aim of this study was to clarify the applied initial forces and moments by different aligners of various materials and manufacturing methods.
Methods:
The finite-element-method was used to analyze the forces and moments generated by the aligners on a maloccluded tooth. Plaster models of dental arches with a mesiorotated tooth 11 were fabricated, digitized and virtually analyzed. Four types of aligners with various layer thicknesses were selected: two splints with novel shape memory properties: a printable aligner made of the resin Tera Harz TC-85 DAC (Graphy Inc., South Korea) and a self-manufactured aligner consisting of the components polypropylene carbonate and thermoplastic polyurethane. The other two aligners were conventional, thermoformable aligners: CA® Pro Clear Aligner (Scheu Dental GmbH, Germany) and Erkodur-al (Erkodent Erich Kopp GmbH, Germany).
Results:
The force and moment analyses showed that the thermoformable CA® Pro Clear Aligner exhibited the highest values. The thermoformed Erkodur-al aligner showed the lowest force loads for all layer thicknesses. The Graphy printed splint showed similar results compared to Erkodur-al at layer thicknesses of 0.40 mm and 0.50 mm.
Conclusions:
To avoid periodontal overloading, aligners with lower force and moment delivery should be chosen for this type of tooth movement.
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