Do root canal wear braces that is in the teeth after root canal treatment crown repair, generally not harmful, but a few people may appear abutment tooth caries, root fracture, apical inflammation problems. 1. Abutment caries: patients in the production of porcelain crowns need to prepare the dental tissues, if the shape is not standardized, to obtain the mold is more vague, it is likely to lead to micro-leakage of the edge of the crown, ultimately leading to abutment caries. 2. Root fracture: If the tooth itself has dental nerve inflammation, there will be a reduction in the resistance of dental hard tissue. In the process of root canal treatment, excessive preparation of the root canal or excessive pressure of root filling will cause root fracture. 3. Root tip inflammation: patients with imperfect root canal treatment, there is still infected material, or there are missed root canals, may also cause bacteria to the apical foramen outside the invasion, which leads to the emergence of apical inflammation. For example, redness, swelling or pus in the mucosa. Do root canal treatment wearing braces, during this period must be perfect root canal treatment as well as crown repair, so as to effectively avoid bringing the above points of harm.