This fact is from Angles Classification in Orthodontics. It is a commonly tested concept in NEET MDS examinations. Understanding this fact is crucial for answering MCQs correctly.
Class I = normal molar relationship crowding anterior
Class II Division 1 = proclined upper incisors overjet increased
Class II Division 2 = retroclined upper incisors deep bite
Class III = mesial lower molar anterior crossbite prognathism
Dewey-Anderson modification of Class I.