Straighter teeth not only improve your appearance but also the way the teeth bite together, while also making them easier to clean, thereby reducing the risks of tooth decay, gum disease, mouth sores, tender or bleeding gums, bad breath, and possible tooth loss.Orthodontics is the branch of dentistry that corrects teeth and jaws that are positioned improperly. Crooked teeth and teeth that do not fit together correctly are harder to keep clean, are at risk of being lost early due to tooth decay and periodontal disease, and cause extra stress on the chewing muscles that can lead to headaches, TMJ syndrome and neck, shoulder and back pain. Teeth that are crooked or not in the right place can also detract from one's appearance.

Orthodontic treatment can focus on dental displacement only, or deal with the control and modification of facial growth. In the latter case it is better defined as “dentofacial orthopedics". In severe malocclusions that can be a part of craniofacial abnormality , management often requires a combination of orthodontics and jaw surgery or orthognathic surgery.