Tooth decay, also known as insect tooth, professionally known as dental caries, generally in the early stage of caries, even caries lead to pulpitis stage, are not caused by significant swelling, once caries caused by swelling, at least means that caries has developed to the stage of apical inflammation. Simply repairing the caries is certainly not a complete cure, but must be targeted at the tooth for systematic root canal treatment, the pulp will be opened so that the inflammation in the pulp to be fully released, in the continuous change of medicine at the same time so that the pulp exudate to be fully drained. If the drainage is not thorough enough, you can also consider incision and drainage in the corresponding area where swelling occurs, after the pus is completely released, and then apply the cementum tip combined with the paste to carry out the root canal treatment, and finally apply the crown restoration to protect the tooth, which is the whole process of treatment.