What are the factors that cause pain in orthodontic treatment?

Orthodontists believe that orthodontic pain is due to various factors, such as age, gender, pain threshold for each patient, amount of force applied, emotional state, amount of stress, and the patient’s past experiences with pain. In fact, the force exerted on the teeth involves an inflammatory response that includes pain in the oral environment, which is caused by the movement of the teeth. This response changes blood flow after orthodontic force is applied.