This cluster of papers encompasses a wide range of topics related to endodontic research and practice, including the use of root canal irrigants, properties and applications of mineral trioxide aggregate, the role of Enterococcus faecalis in treatment failure, revascularization techniques, and regenerative endodontics. It also covers the challenges and outcomes of endodontic treatment, the use of nickel-titanium instruments, advancements in imaging with cone beam computed tomography, and the potential for dental pulp regeneration.