Evaluating the interaction of local anesthetic agents with sequential and continuous chelation in root dentin - An

Objectives: Adequate anesthesia is imperative to perform root canal treatment. In teeth that do not respond to conventional anesthetic procedures, intrapulpal injection of local anesthetics (LAs) is commonly performed. It remains unknown if these anesthetic solutions interact with irrigants that are subsequently used during root canal preparation. This study aimed to investigate if LA solution when interacting with endodontic irrigants forms debris. Materials and Methods: Sixteen single-rooted human mandibular premolars were used. Access opening was done and intrapulpal anesthesia was delivered. In Groups I and III, 2% Lignocaine HCl; Group II and IV, 4% Articaine HCl. Cleaning and shaping were done with Protaper gold and irrigants of the following groups: Group I and II: 3% sodium hypochlorite (NaOCl) and 17% ethylenediaminetetraacetic acid (EDTA); Group II and IV: NaOCl + 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP). Scanning electron microscopic (SEM) analysis was done. Results: SEM analysis showed the least debris formation in samples treated with 2% Lignocaine + sequential irrigation in all the three regions. Apical third has more amount of debris with a significant difference. Conclusions: Debris formation was lesser with 2% Lignocaine using sequential irrigation (NaOCl and EDTA) compared to continuous chelation (NaOCl + HEDP). Regardless of the irrigation protocol, 4% articaine resulted in greater debris accumulation than 2% lignocaine.