According to what you said, your front teeth are crowded. Generally speaking, tooth extraction is necessary. If you don't pull out your teeth and simply expand your arch, you should consider your face, age, occlusal relationship between the upper and lower jaws and so on. Maybe the effect is not very good, or the possibility of tooth extraction is greater. Orthodontics is very complicated, and it can't be decided by just one question. It is recommended to go to the stomatology department for a special examination.