I am often asked when crowded or crooked teeth should be straightened? Depending on the individual situation some orthodontic treatment can be undertaken at a young age. Sometimes crowded and crooked teeth can be prevented by early treatment. 

To ensure early detection of situations that can be helped with early treatment, a child should have a checkup by the family dentist at intervals of about six months, starting at about 2 1/2 to 3 years of age. Overcrowded and crooked teeth are often visible with the arrival of the four permanent incisors and the four permanent molars at around age six. 

Prompt treatment is recommended when teeth are overcrowded. Some baby teeth may be removed ahead of schedule (serial extraction) to allow nature to do a certain amount of tooth straightening. Known as interceptive orthodontics, early extractions involve a one-by-one extraction in a well-planned sequence.