The hazards of not straightening teeth are as follows: 1, from the perspective of oral hygiene, crowded teeth is not conducive to oral self-cleaning role. In addition to the use of brushing teeth such as external force exerted to the teeth cleaning role, the mouth will secrete saliva, including when eating is also a food flush, these are the self-cleaning role of the teeth. Crowded uneven teeth have a lot of surfaces blocked by neighboring teeth, so not only brushing, including the self-cleaning effect of the mouth, can not enter the blocked teeth, oral hygiene will be poor, the incidence of caries will be higher, periodontal problems will also be more than normal; 2, crowded uneven teeth are easy to accumulate tartar, will cause bleeding gums, swollen gums, bad breath and a series of problems; 3, crowded The uneven teeth firstly give a not very good feeling in the face, so crowded teeth will most importantly affect the aesthetic problem; 4, crowded teeth will affect the chewing function, such as the back teeth, large groove teeth and other teeth that bear more chewing function, if there is crowded uneven, there is no great occlusal contact with the teeth of the opposite jaw, the chewing of this side may be affected; 5, uneven teeth It will also affect the pronunciation, for example, if some patients have uneven teeth and their front teeth do not bite closely together, they may have a series of problems such as leakage when they speak, which will affect the normal pronunciation.