& ltp> In fact, the protrusion of the mandible is the ground covering the sky. There are many reasons for the formation of the ground covering the sky, most of which are congenital factors, but as you said, the protrusion of the mandible is gradually formed because of breathing through the mouth, and this situation also exists. & lt/p & gt； & ltp> However, due to mandibular protrusion, conservative improvement cannot achieve a radical effect, and it needs to be improved through bimaxillary surgery. & lt/p & gt； & ltp> If you want to talk about the specific method of writing a good book, you should go to a regular hospital for face-to-face consultation to determine whether jaw surgery or bimaxillary surgery can improve it. & lt/p & gt； & ltp style = \ " text-align:center \ " & gt； & ltimg src = \ "/uploadfile/image/20191202/1575275481906327.jpg \" title = \ "\" alt. 15 1 \ " border = \ " 0 \ " vspace = \ " 0 \ " style = \ " width:500 px； Height:151px; \ "/>； & lt/p & gt； & ltp> In addition to bimaxillary surgery, it is recommended that you do some rhinitis surgery before or after bimaxillary surgery. The prominent maxillofacial condition has a certain relationship with rhinitis. Therefore, radical surgery for rhinitis is also recommended to avoid other problems in the later stage. & lt/p & gt； & ltp> However, it should be reminded that if you want to do bimaxillary plastic surgery and rhinitis surgery, it is recommended to do them separately. & lt/p & gt； & ltp> Because it will be difficult to breathe through the mouth in the first few days after bimaxillary surgery, it is not recommended to carry out the two operations together, and it will be easier to separate them. & lt/p & gt；