The hazards of crooked teeth are as follows: 1, misaligned teeth are not easy to clean, it will lead to dental caries, gingivitis, periodontal disease; 2, excessive anterior protrusion of the front teeth, in the case of trauma, easy to break; 3, chewing function is affected, teeth are not aligned, the bite does not fit, it will affect the pronunciation and chewing function, the decline in chewing function will affect the gastrointestinal tract digestive function, which will lead to gastrointestinal disorders; 4, patients with mandibular retraction If you are a patient with mandibular retraction, you will snore easily when you sleep, which will affect the function of the airway; 5. Aesthetic problems, such as gummy smile, bun in the sky or maxillary protrusion, mandibular retraction and other bony deformities, which will affect the patient’s mental health, produce low self-esteem, and affect the socialization.