The main symptoms of dental periapical infection are: 1. Pain. Chronic periapical infection can result in long-term distension and pain in the apical region, discomfort from biting, and even inability to bite hard objects. When the acute attack of periapical inflammation causes severe throbbing pain, the affected tooth has a pronounced elongation and is unable to bite. 2. Redness, swelling, pressure and pain of the gums in the apical area, fistulas and abscesses appear. Due to long-term apical zone inflammation resulting in bone destruction, sinus tracts for pus drainage will appear at the corresponding apical zone gums, with mucosal redness, severe polyps, and even abscesses. 3. In people with low body resistance and children, the acute attack of dental periapical periodontitis will cause facial swelling, restricted mouth opening, enlarged lymph nodes, and low fever. 4. obviously leads to temporary loosening of the corresponding tooth.