The Evolution of Clear Aligner Therapy: A 25-Year Review of Aesthetic and Clinical Outcomes

This review evaluates the evolution and impact of clear aligner therapy (CAT) over the past 25 years. Since its introduction by Align Technology in 1999 as Invisalign, CAT has transformed orthodontic treatment with its clear, removable aligners. Materials and methods: A comprehensive literature search was conducted across databases, including PubMed, Cochrane Library, ScienceDirect, Web of Science, Scopus, and Google Scholar, covering studies published from 2000 to 2025. Resultsː The review highlights technological advancements, clinical effectiveness, patient satisfaction, limitations, and future prospects of CAT, providing insights into its role in contemporary orthodontics. Conclusionsː CAT has made significant strides in aesthetics, comfort, and convenience over the past 25 years. Despite technological advancements, challenges remain in achieving predictable outcomes for complex tooth movements. Success depends on appropriate case selection, patient compliance, and practitioner expertise.