Introduction: Predictable intrusion of maxillary anterior teeth remains biomechanically complex in clear aligner therapy. This study examines the effect of different attachment placements on intrusion efficiency using finite element analysis (FEA). Methods: A 3D model based on CBCT scans was developed and meshed using ANSYS Workbench. Four attachment configurations were simulated under vertical forces (11.82–59.10 N). Intrusion displacement and Von Mises stress distribution in teeth, PDL, and bone were analyzed. Results: The configuration with attachments on both central and lateral incisors (CL) yielded the greatest vertical displacement (0.0091 mm) and optimal stress transmission. Configurations limited to posterior attachments showed minimal tooth movement (0.0046 mm). Conclusions: Strategic anterior attachment placement significantly enhances biomechanical predictability and efficiency in clear aligner-induced intrusion movements.
Shah et al. (Sun,) studied this question.