Gums that are swollen and painful to varying degrees throughout the mouth are caused by periodontitis. Periodontitis is caused by a buildup of infected material around the gums, such as food debris, tartar, and plaque, which can cause the gums to become red, swollen, inflamed, and prone to bleeding, which in turn can trigger the sensation of swollen, painful gums. Gum swelling and pain if the existence of a tooth is localized, may also be the emergence of gingival papillitis, is due to long-term food blockage caused by the gums, gum swelling and pain if the appearance of the root of the tooth in the cusp of the site, is an indication of the tooth suffers from apical periapical periodontitis, due to the tooth caries did not undergo timely treatment, the development of the pulp inflammation, inflammation and spread along the apical foramen to the periapical bone tissues, making the teeth and gums The teeth and gums become swollen and painful.