This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Dental
[{'content': 'Index for orthodontic treatment needs is/are: \nSelect and explain. \nA. SCAN index, B. ICON index, C. DAI index, D. All of the above', 'role': 'user'}, {'content': 'Answer: D \nExplanation: SCAN index is the synonym for Index for Orthodontic Treatment Needs (IOTN). IOTN index was developed by BROOK and SHAW to link dentofacial variation to perceive\xa0esthetic impairment.\nKey Concept:\nThe other Orthodontic treatment need indices are:\n\nHandicapping Labio-lingual Deviation Index (HLD) (Draker)\nDental Aesthetic Index (DAI) (Cons et al)\nIndex of Complexity, Outcome and Need (ICON) (Daniels & Richmond)', 'role': 'assistant'}]