16 years old, to be honest, it's a little late for you to realize this problem now. Normal mandibular occlusion is that the upper teeth bite in front of the lower teeth. That's what happens when you change your teeth You should correct it then. It's not good now when you are old ~ ~ Long-term dislocation of jaw will make the maxilla develop abnormally. After that, the chin protrudes and the upper teeth and upper lips retract, which is not good-looking. Your urgent task now is to go to a professional stomatological hospital for orthopedic surgery. Your situation is a little difficult and it may take a long time to correct it. In another two or three years, you'd better go to the hospital for consultation first.