Malocclusion refers to a misalignment of the teeth and jaws, which can affect how the upper and lower teeth fit together when the mouth is closed. This condition can lead to various dental issues, including difficulty in chewing, speech problems, and increased wear on teeth. It can be caused by genetic factors, thumb sucking, or early loss of baby teeth. There are different types of malocclusion, classified as Class I, Class II, and Class III, based on the relationship between the upper and lower teeth. Treatment options may include braces, retainers, or, in severe cases, surgery to correct the alignment and improve oral function.