Gum bulge may be related to apical periodontitis, gingivitis, apical cyst, etc. 1. Periapical periodontitis: mainly caused by bacterial infection, dental trauma, occlusal trauma, etc., often showing spontaneous pain, occlusal pain, apical gingival swelling, etc., which may lead to the emergence of bulging gums. 2. Gingivitis: mainly caused by localized plaque, food impaction, misalignment and crowding of teeth, often showing bleeding when brushing, biting hard objects, localized itching and swelling of the gums, pain, bad breath, etc., which may lead to the emergence of gingival bulging. 3. Apical cysts: mainly due to pulpitis caused by untreated, infection, do not pay attention to oral hygiene can also induce the disease, often showing hemispherical bulging, mild pain, repeated gum abscess, etc., may lead to the emergence of gum bulging. Therefore, there are more causes of gum bulge, if the symptoms do not improve or aggravate, it is recommended to choose to seek medical attention in time.