HOME - Clinical cases - Endodontics
20 June 2023

New 2-in-1 root canal irrigants

Lara Figini

Disinfection of the root canal system is critical to endodontic success and can be achieved through mechanical instrumentation, irrigation with disinfectant solutions, and the application of intermediate root canal dressings. Literature studies have demonstrated that mechanical instrumentation alone cannot completely engraft microbes present in accessory canals, anastomoses and deep dentinal tubules. Approximately 35-53% of the root canal surface remains intact during mechanical instrumentation which results in biofilm retention. 

This highlights the need for a root canal irrigant capable of removing the smear-layer and disinfecting the root canal system at the same time. Manufacturers have now combined a chelating agent and a disinfectant in a single solution (2-in-1 irrigant). The use of this type of irrigant would presumably reduce treatment time and should increase the effectiveness of root canal therapy.

These types of 2-in-1 irrigants include:

  • QMix 2 in 1 (Dentsply Sirona, Charlotte, NC, USA) able to remove the smear layer as effectively as 17% EDTA and is an effective antimicrobial agent against Enterococcus faecalis (E. faecalis) biofilms.
  • Irritrol (Essential Dental Systems, Hackensack, NJ, USA) which is a recently introduced single-phase disinfectant endodontic irrigating solution consisting of EDTA and chlorhexidine (CHX).
  • SmearOFF (Vista Dental Products, Racine, WI, USA) is a recently introduced smear layer removal agent in endodontics. According to the manufacturer, mixing SmearOFF with NaOCl does not cause precipitation. This negates the need for a second rinse after NaOCl irrigation. To date, no comparative studies are available to evaluate the physical and chemical characteristics properties of 2-in-1 irrigation solutions.

Materials and methods

In a study published online in April 2023 in the Journal of Dentistry, the authors evaluated the ability to remove the smear layer from canals, the antibacterial activity and the cytotoxicity of three new 2-in-1 root canal irrigants (chelator + antibacterial). 

Forty single-rooted teeth were mechanically instrumented and irrigated with QMix, SmearOFF, Irritrol or 0.9% saline (control group). Each tooth was evaluated for smear layer removal using scanning electron microscopy. Precipitation after interaction with sodium hypochlorite (NaOCl) was evaluated with 1H nuclear magnetic resonance and mass spectroscopy. Laser scanning confocal microscopy was used to evaluate the antimicrobial activity of irrigants against Enterococcus faecalis biofilms.

Clonogenic assays were performed on Chinese hamster V79 cells to evaluate the short-term and long-term cytotoxicity of irrigants.


No significant difference was found between QMix and SmearOFF in the elimination of smear layers from the coronal third and middle third of the root canal. In the apical third, SmearOFF has been shown to be able to remove the smear-layer more effectively. Irritrol has been shown to incompletely remove the smear-layer from all thirds of the channel. When mixed with NaOCl, precipitation was only evident with Irritrol. QMix demonstrated a higher E. faecalis cell death rate and lower biovolume. SmearOFF showed a greater decrease in biovolume than Irritrol, although Irritrol led to a higher cell death rate. Irritrol was more cytotoxic than all other short-term irrigants. In terms of long-term cytotoxicity, both Irritrol and QMix were found to be cytotoxic.


From the data of this study, it can be concluded that QMix and SmearOFF offer better results in the removal of the smear layer and in the antimicrobial activity. QMix and Irritrol are more cytotoxic than SmearOFF.

Nidambur Vasudev Ballal et al. "Biological and chemical properties of 2-in-1 calcium-chelating and antibacterial root canal irrigants," Journal of Dentistry, Volume 134, 2023, 104526, ISSN 0300-5712, https://doi.org/10.1016/j.jdent.2023.104526.

Related articles

Dr. David Jaramillo, a professor at UTHealth Houston School of Dentistry, provided an overview of the latest research using the GentleWave System. 

Study evaluated antimicrobial efficacy

Current irrigation techniques are based on the use of sodium hypochlorite but do not guarantee success in eliminating microorganisms from the root canal.

Author - Dr Marco Martignoni

Irrigation of root canals is key to improve the removal of bacteria, pulp tissue, smear layer and debris from the root canal system (1), reducing the risk of post-treatment disease. In fact, it is...

The main purpose of regenerative endodontic therapy (RET) is the eradication of root canal infections and the stimulation of bone healing, with the aim of obtaining an increase in root wall thickness...

The EdgePRO system offers a more effective, innovative cleaning and disinfection technology for the endodontic community

BIOLASE, the global leader in dental lasers, and EdgeEndo, a global leader in commercializing endodontic products, announced today the FDA 510(k) clearance of the EdgePRO system for endodontists...

Read more

USA     30 November 2023 - 02 December 2023

2023 Dental Implant Conference

Nov. 30-Dec. 2, Chicago

The 2023 Dental Implant Conference offers an intensive educational program of innovative techniques and procedures for the entire implant team, presented by an internationally renowned faculty of...

Oral cancer (OC) is one of the most common forms of head and neck cancer and continues to have the lowest survival rates worldwide, despite advances in research and therapy. The prognosis of OC has...

Due to high demand, applications have opened early for Glidewell’s 2024 Guiding Leaders program. Returning for its fourth year, Guiding Leaders is an in-person business and leadership development...

If there’s one word that encapsulates Lauren Chapman’s adult life, it’s leader. From captain of the cheerleading team as a Penn State undergrad, to serving as a Surface Warfare Officer in the...

Clinux CAD, the world’s first cloud-based CAD software designed for dentists, is proud to announce three innovations, expanding its range of possibilities for customers.



Most popular