Evaluation of effects of different sizes and shapes of attachments during rotation, tipping, and torquing in clear aligner therapy – A finite element study

Abstract

OBJECTIVE: To evaluate the effect of different shapes and sizes of attachments used for rotation, tipping, and torquing tooth movement in clear aligner therapy. MATERIAL AND METHODS: Using computer-aided design/computer-aided manufacturing technology, 15 replicas of the upper right human canines were produced. Finite element analysis (FEA) was utilized to mimic tooth movement by applying a constant force of 2.942 N to these models, which contained various forms and sizes of composite attachments. Analysis was done on the stress on different dental structures and the displacement of the attachments. RESULTS: The outcomes demonstrated that tooth movement during clear aligner treatment was considerably impacted by attachment size and shape. Rectangular beveled attachments with dimensions of 3.5 mm × 1.2 mm × 3.5 mm showed the greatest rotating mobility. Triangular beveled attachments with dimensions of 5 mm by 0.8 mm by 2 mm produced the most displacement during tipping motion. For torquing motions, rectangular power ridge attachments with dimensions of 0.5 mm × 0.5 mm × 5 mm worked well. CONCLUSION: The size and geometry of composite attachments were shown to be extremely important in regulating tooth movement during clear aligner treatment, according to this FEA research. Greater displacement is produced when smaller attachments with less surface area dissipate more force. When using clear aligner therapy, orthodontists may optimize treatment plans, shorten treatment times, and provide more predictable results by having a better understanding of the biomechanics of various attachment designs.

Keywords

• clear aligner therapy
• composite attachments
• finite element analysis
• orthodontic treatment
• tooth movement