Numerous indices have been proposed to help orthodontists classify how complex their cases are. Most classifications rate as difficult the cases that need correction of overjet (the upper front teeth sitting forward of the lower front teeth), an underbite of the front teeth, impacted teeth, an open bite in the side teeth, and treatment of patients who have missing teeth.
Crossbites in growing patients, and deep and open bites at the front, are easier to resolve.
Cases with no bite problem are easy – rotated teeth, high canines.
Treatment in children and adolescents is easier and quicker than in adults.
This answer is for general information. Your own case needs an examination by an orthodontist.