Aligner-driven tooth movement: Biomechanical fundamentals and clinical implications – A review

ABSTRACT Introduction: Clear aligner therapy (CAT) has become a widely accepted alternative to fixed orthodontic systems, offering esthetic appeal, patient comfort, and digital customization. Despite its popularity, CAT still struggles with issues of efficacy and consistent treatment outcomes. Advancements in biomechanics play a key role in resolving these limitations. Hence, this review discusses the biomechanics of individual tooth movements – rotation, tipping, expansion, intrusion, extrusion, torque, and distalization, emphasizing the role of attachments. Methods: Relevant research publications were identified through comprehensive searches on databases such as Scopus, PubMed, and Google Scholar using keywords including clear aligners , biomechanics , orthodontics , and CAT . Results: A total of 38 articles were selected and utilized to formulate this narrative review. Discussion: CAT relies on shape molding mechanics, material properties, and the integration of optimized attachments and auxiliaries significantly enhances their efficacy and predictability in complex movements to deliver controlled forces. Advancements continue to expand the clinical scope of CAT, positioning it as a viable option for comprehensive orthodontic care.