Swollen and painless gums may be caused by chronic gingivitis, chronic periodontal abscess, chronic periapical periodontitis, and medicated gingival hyperplasia. 1. Chronic gingivitis: gingivitis occurs due to poor oral hygiene, resulting in plaque, calculus and other deposits near the gingival margin. Patients may show swollen and bleeding gums and enlarged gingival papillae, but without pain. 2. Chronic periodontal abscess: Because of the periodontal pockets, or the deep periodontal tissues in the limited purulent inflammation, so the gums are swollen but not painful. 3. Chronic apical periodontitis: due to the usual lack of good oral hygiene care, leading to germs stimulate the root tip area, may induce apical periodontitis. Inflammation will spread to the gums, and the symptoms of swollen gums but no pain can appear. 4. Pharmacological gingival hyperplasia: due to long-term use of antihypertensive drugs, anti-epileptic drugs, etc., may cause gingival tissue hyperplasia, resulting in swelling of the gums, but there is no pain. When there are swollen gums but no pain, you should go to the hospital in time to clarify the cause of the disease and treatment, so as not to delay the condition.