The document describes the Index of Orthodontic Treatment Need (IOTN), which comprises two components: the Dental Health Component (DHC) and Aesthetic Component (AC). The DHC uses a scale of 1 to 5 to assess malocclusions based on their severity, focusing on the single worst feature. These features are represented by the acronym MOCDO, standing for missing teeth, overjet, crossbites, displacement of contact points, and overbite. The AC uses a scale of 1 to 10 based on photographs to assess dental attractiveness. The IOTN provides a standardized measure of orthodontic treatment need.