The role of soft tissue analyses in orthodontic diagnosis and treatment planning: from conventional approaches to contemporary digital and artificial intelligence-supported evaluations: A review

Orthodontic diagnosis and treatment planning have traditionally relied on the evaluation of dental and skeletal relationships. However, contemporary orthodontic success is assessed not merely by achieving ideal occlusion, but also by maintaining or enhancing facial aesthetics, profile harmony, lip position, and soft tissue balance. Soft tissues are not passive coverings of hard structures; rather, they define facial perception, shape the boundaries of orthodontic intervention, and determine the aesthetic acceptability of treatment outcomes. Consequently, soft tissue analyses have evolved from being complementary assessments to becoming central elements in defining treatment objectives. This review discusses the historical development of soft tissue analyses, classical reference lines, the Arnett-Bergman approach, the influence of growth and ethnic variation, profile changes in extraction versus non-extraction treatments, three-dimensional facial analyses, and artificial intelligence-supported contemporary approaches. Current literature demonstrates that soft tissue analyses are critical not only diagnostically but also prognostically and aesthetically in orthodontic decision-making.