The reason for the formation of large and small faces is long-term unilateral chewing and occlusal dysfunction. Sticking to bilateral chewing can be improved (note: if you chew on the left side for a long time, don't think that chewing on the right side can be improved now, it will only make your face more deformed, and you must stick to bilateral chewing to improve it). Skew body skeleton. The main reasons are: incorrect sitting posture, love to stretch your legs, only use one shoulder to hang your bag ... Improvement methods: get rid of bad behavior habits and insist on practicing yoga.