If there is a big or small face, there is no excessive requirement for the usual sleeping position. The appearance of large and small faces may be related to the habit of sideways chewing. Regular sideways chewing will cause one side of the chewing muscle to be too strong while the other side is relatively weak, resulting in a slightly larger face on one side and a slightly smaller face on the other side. If the situation of big and small face occurs, it is recommended that the patient better go to the regular dental hospital outpatient examination. If there are no oral problems, it is recommended that patients chew food with both sides of the teeth in turn. For the usual sleeping position really does not have too many requirements, patients can choose the position they feel comfortable, preferably the left side position, right side position alternately.