Effectiveness of Laser-activated Photoacoustic Flow in One-visit Revision of Teeth With Apical Periodontitis

The main objective of the clinical randomized study is to examine the effectiveness laser-activated irrigation (LAI) on the removal of intracanal microorganisms and the healing of an inflammatory periapical lesion of a tooth after a one-visit revision of teeth with apical periodontitis. The main questions are: 1. Does LAI reduces the occurrence of postoperative pain, compared with sonic-activated irrigation? 2. Is antimicrobial efficacy of LAI greater than the antimicrobial efficacy of sonic-activated irrigation? 3. Is periapical lesion healing after LAI application better than after sonic-activated irrigation? Researcher will compare LAI and sonic-activated irrigation in patients with signs and symptoms of chronic apical periodontitis requiring revision. Participants will be assigned to two experimental groups depending on the final root canal disinfection protocol. Postoperative pain will be assessed via a questionnaire that participants will receive after the treatment and which they will complete over a period of seven days. Microbiological samples will be collected from the root canal and real-time PCR analysis will be performed to evaluate antimicrobial efficacy. Assessment of periapical lesion healing will be performed by comparing CBCT scans obtained before the treatment and one year after.