Advancements in Irrigation Delivery Systems: Assessing the Cleaning Efficiency of Negative Pressure versus Positive Pressure Techniques

Abstract

Effective irrigation remains a critical determinant of success in root canal therapy, as it ensures the removal of debris, biofilm, and microorganisms from complex canal anatomies. This study aimed to evaluate and compare the cleaning efficiency of negative pressure and positive pressure irrigation delivery systems. Forty extracted human teeth with standardized canal preparations were divided into two groups: one irrigated using a negative pressure system (EndoVac) and the other with a conventional positive pressure syringe–needle technique. Both groups utilized sodium hypochlorite and EDTA as irrigants under controlled conditions. The extent of debris removal, irrigant penetration, and apical extrusion were analyzed using stereomicroscopic and digital imaging methods. The results demonstrated that the negative pressure system achieved deeper irrigant penetration and superior apical cleanliness while minimizing irrigant extrusion beyond the apex. In contrast, the positive pressure technique showed limited irrigant exchange in the apical third and higher extrusion risk. These findings suggest that negative pressure irrigation offers improved safety and cleaning efficiency compared to traditional positive pressure systems, representing a significant advancement in modern endodontic irrigation technology.