Objectively speaking, orthodontic appliances are some of the more sophisticated products, on the soundness of this product cannot be compared with the large metal products; the orthodontic adhesive material, it is necessary to ensure the strength of its bond, and can not be too strong to cause trouble after the appliance removal of adhesive material, bonding materials is innocuous, multifaceted restrictions make orthodontic adhesive cannot compare with adhesives for industrial.     Comprehensive above two aspects, orthodontic appliance damage and loss, in the current technical conditions can not be completely avoided.
   However, with the development of modern science and technology, orthodontic appliance and the strength of the adhesive has been able to meet the general clinical needs, therefore, if there is no accident, the general should not occur damage and loss to the appliance. The cause of these conditions, it is because some patients did not pay attention to the doctor's orders in the process of wearing, eat some excellent viscosity foods, or the child unconsciously to bite appliance, can cause damage or loss, therefore, parents and children should in good accordance with the doctor's advice to use the appliance.