Laser application for root canal disinfection during endodontic therapy, Примена на ласери за дезинфекција на коренски канали во тек на ендодонтска терапија

<jats:p>Effective cleaning, irrigation, and sterilization of root canals are essential criteria for successful endodontic treatment of infected root canal systems. Conventional chemomechanical procedures for root canal debridement cannot reliably ensure complete disinfection of the entire endodontic space, particularly in anatomically complex areas such as the apical delta and accessory canals. Following mechanical instrumentation, approximately 35% of the dentinal walls remain covered with bacterial biofilm, and even after the application of antimicrobial agents, root canals are not completely disinfected. Considering that sterility of the root canal system is a key factor for successful treatment of apical periodontitis, continuous efforts have been made to identify more effective disinfection methods. Over the past decade, the use of lasers for root canal disinfection and cleaning has increased significantly, although their full potential is still under investigation. The aim of this study was to explain the fundamental principles of laser–tissue interaction within root canals and to compare laser-assisted endodontic treatment with conventional irrigation using 3% sodium hypochlorite and ultrasonic activation in teeth diagnosed with chronic apical periodontitis.This in vivo study was conducted on 60 teeth diagnosed with chronic apical periodontitis, which were randomly divided into three groups. Mechanical preparation of the root canals was performed using a standardized protocol with nickel–titanium rotary instruments, followed by continuous irrigation with 2.5% sodium hypochlorite (NaOCl) in combination with 17% ethylenediaminetetraacetic acid (EDTA). After completion of chemomechanical preparation, the following disinfection protocols were applied: (1) 2.5% NaOCl in combination with EDTA, (2) 2.5% NaOCl with sonic activation using an endoactivator, (3) Application of a diode laser for sterilization of the root canal system. Treatment effectiveness was assessed through radiographic evaluation of the periapical status. Radiographic examinations were performed at three-time intervals: before treatment, at 3 months, and at 6 months follow-up. The results of this study demonstrated that all applied disinfection protocols led to a reduction in periapical lesions over the observation period. However, the most pronounced decrease in Periapical Index (PAI) values was observed in the group treated with laser-assisted disinfection.</jats:p>