Prolonged redness and swelling of the gums may be caused by periodontitis, chronic apical periodontitis, wisdom tooth pericoronitis and other causes. The cause should be clarified by timely consultation. 1. Periodontitis: Periodontitis is a destructive disease, related to microorganisms and host response. It is a chronic inflammation caused by local factors stimulating the periodontal tissues, which can be manifested as bleeding gums, bad breath, long-term redness and swelling of the gums. 2. Chronic apical periodontitis: Chronic apical periodontitis has many causes, which may be related to bacterial infection, traumatic factors, and chemical stimulation. It leads to long-term redness and swelling of the gums, pain, and biting pain. 3. Wisdom tooth pericoronitis: when the wisdom teeth and wisdom teeth erupt, the crown can be partially or completely covered by the soft tissue of the gums, forming a blind pocket between the gingival flap and the crown, and food and bacteria can easily be embedded in the blind pocket, when the body’s resistance decreases, and the toxicity of the local bacteria increases, the wisdom tooth pericoronitis may occur, resulting in long-term redness and swelling of the gums and pain, and other symptoms. There may be other reasons for long-term redness and swelling of the gums, so you should consult your doctor in time to clarify the specific cause and get appropriate treatment if necessary.