Gum bulging after plugging may be caused by filling suspension irritation, nerve necrosis, apical inflammation and so on. 1. Filling suspensory: filling suspensory compression of the gums during filling leads to swelling of the gums and gum bulging after filling. 2. Nerve necrosis: dental caries close to the nerve, after filling the nerve necrosis, inflammation spread to the root tip, root tip inflammation can not be discharged resulting in gum bulging. 3. apical inflammation: after the tooth root canal treatment, root canal treatment is not complete, root fissure and so on, leading to inflammation at the root tip, inflammation from the gums mucosa to the outward discharge of pus, thus forming a gum bulge. Gum bulge after plugging the tooth may also be other reasons, not blindly self-treatment, please go to the hospital in a timely manner, after a professional physician’s examination, to clarify the cause of the active treatment, in order to facilitate the recovery of the condition.