: The "Rule of Fifths" is used to assess facial harmony, where the face is ideally divided into five equal segments, each roughly the width of one eye.

: Ideal smiles typically feature symmetrical gingival margins and specific axial inclinations of the anterior teeth. ⚙️ II. Biomechanical Principles

Biomechanics involves using mechanical principles to control and guide tooth movement predictably while minimizing side effects. Esthetics and Biomechanics in Orthodontics: 2nd edition

Effective treatment planning begins with an individualized diagnosis of the patient's soft tissue and dental proportions.

: Focuses on "smile arc protection," ensuring the curve of the upper teeth follows the curve of the lower lip.