Pulpitis rarely causes gum swelling; it is generally inflammation at the apex of the tooth root that leads to it, or gingivitis causing swollen gums. Pulpitis is a bacterial infection of the tooth's hard tissues. If not treated promptly and the progression of the decay is not halted in time, it can infect the tooth nerve and cause pulpitis. At this stage, the bacterial infection is confined to the pulp tissue, which is the interior of the tooth. The gums are the supporting tissues of the teeth. If pulpitis is not treated promptly and the inflammation further progresses to the root apex area, and if the inflammation in the root apex area cannot be effectively drained, it will lead to pus discharge outward to the mucosa or skin, forming swollen gums, or a gum abscess, or swelling around the teeth due to food residue remaining after eating. Therefore, pulpitis generally does not cause swollen gums.