Pay attention to whether you like to sleep on your side, whether you like to sleep on your left side, and whether your teeth are deformed. If the size of your left and right faces is not obvious, just adjust your sleeping posture and other habits that cause facial deformation. If it is too serious, you should go to the plastic surgery department or the dentist to ask: I sleep comfortably on my left side and my teeth will not deform. What caused this! Answer: You can look at the gap between the left and right teeth. You should observe others more, compare them with the right ones, see what their crooked teeth are like, and then compare them with yourself. You can look at the symmetry and up-and-down arrangement of teeth, or you can look at your whole face in the mirror for comparison. If it's not a big problem, just adjust your sleeping posture and dental habits to get the witness of the questioner: thank you!