Recurrence of clinical symptoms in an endodontically treated tooth following COVID-19 vaccination: a case report.

The aim of this report is to present an unusual case in which clinical symptoms recurred in an endodontically treated tooth after the patient received a COVID-19 vaccination. A 61-year-old woman reported severe pain in her maxillary right lateral incisor 2 months after completion of root canal treatment. The patient reported developing the clinical symptoms a few days after receiving the second dose of the Pfizer-BioNTech COVID-19 vaccine. Clinical examination revealed no extraoral or intraoral swelling, but the incisor exhibited tenderness on percussion. Palpation of the surrounding tissue did not elicit any tenderness, and no sinus tract was observed. The periodontal probing depths were within normal limits. A periapical radiograph showed no significant change in the radiolucency associated with the treated tooth. The pain had lessened after the use of nonsteroidal anti-inflammatory drugs, and the patient declined any active treatment for the tooth. At the 2-year follow-up, the tooth was asymptomatic, and complete resolution of the periapical radiolucency was observed in radiographic and cone beam computed tomographic images. This case report describes a possible association between COVID-19 vaccination and the onset of self-limiting clinical symptoms in a tooth that had recently undergone endodontic treatment. This case is a reminder that the recurrence of symptoms does not necessarily indicate endodontic treatment failure. No absolute cause-effect relationship can be established between the vaccination the patient received and the recurrence of clinical symptoms in her endodontically treated tooth, but clinicians should not immediately propose an intervention for a tooth presenting with clinical symptoms if the patient has recently received a COVID-19 vaccination. Longer follow-up is needed to assess the success of endodontic treatment.