The medical term for a circumference is antomandibular. treatment of antomandibular after the age of 40 is necessary, but it is not recommended for patients with serious diseases or those with contraindications to orthodontic treatment. 1. There is no age limit for orthodontic treatment, so it is also necessary to treat antomandibular after 40 years old. However, since 40 years old has missed the best age for orthodontic treatment, orthodontic treatment is relatively more difficult and the treatment will take longer than adolescent patients. 2. If you suffer from serious diseases, or have mental illnesses that cannot cooperate with the treatment, and have serious periodontal diseases that cannot be controlled, you should not undergo the treatment. Patients who are 40 years old with anti-mandibular should go to the hospital, improve the examination and communicate with the doctor in detail before deciding carefully whether to have anti-mandibular treatment or not.