Swollen gums that cannot open the mouth should be considered for wisdom tooth pericoronitis, which causes swollen gums, often at the very end of the tooth bed near the throat. This is due to the fact that there is a blind gum pocket around the blocked tooth, which retains a lot of food debris and bacteria. When the body’s immune function is low, this can lead to increased bacterial activity and virulence, resulting in local swelling and inflammation. If you have swollen gums and cannot open your mouth, you should use sufficient antibiotics to reduce inflammation, such as oral cephalosporin, erythromycin enteric capsules, amoxicillin dispersible tablets and metronidazole tablets to reduce inflammation. You can go to the hospital to apply local rinse and medication to the swollen gum area, and apply iodoglycerin or tincture of iodine in the periodontal pocket for local anti-inflammation. If the gum swelling is not in the wisdom tooth, it is possible that the other teeth in the mouth have periapical inflammation. Facial swelling caused by an acute attack of periapical periodontitis, complicated by a gap infection in the jaw, can also cause restricted mouth opening. In this case, in addition to taking antibiotics to reduce inflammation, root canal treatment should be done on the affected tooth.