As you’ve perhaps experienced, not all root canal systems are the same. And their complexities add to the challenge associated with endodontic disinfection.
Canal anatomies can create issues during shaping. Curvatures, oval or flattened canals, and other related conditions make instrumentation challenging.
”Different preparation techniques leave from 10% to 50% of the root canal surface area untouched.” 
As we cover the basics here be aware that a thorough clinical treatise is also available. It presents the details associated with effective endodontic disinfection protocols and the solutions that helped achieve desired outcomes.
The root problem associated with endodontic disinfection
Bacteria are persistent following what are referred to as “chemo-mechanical procedures.” Their resistance to treatment further increases their ability to be unaffected by instruments and irrigants.
Even so, some microorganisms reveal resistance to endodontic disinfection although their opposition to debridement procedures (and NaOCI) is unlikely. The core problem with disinfection has to do with the primary canal lumen and the observed irregularities via preparation.
- Bacteria and certain tissue can elude disinfection modes
- Bacteria can spread via canal pathways into the periodontal ligament prompting disease
The available comprehensive clinical data and related diagrams point to the limitations of instruments and the short retention time of irrigants used within the root canal.
Again, the overall clinical point of view attributes related difficulty to the canal’s complex anatomy. Adequate infection control is necessary in the main canal lumen and throughout the entire root canal system.
Shaping and irrigant delivery as a vital duo in endodontic protocol
The shaping process relies heavily on irrigant delivery for effective disinfection. This is especially relevant to those areas that cannot be reached by files.
The irrigant’s effectiveness in decontamination relies on being delivered as close as possible to the apex thus allowing good exchange and activation. This is an important standard of measurement for endodontic treatment and retreatment.
Your irrigation goals:
- Remove as much bacteria as possible from the root canal area
- Promote apical healing (pending lesion presence)
- Prevent reinfection
There are certain clinical markers that make endodontic disinfection a critical process. Among them are the minimal penetration of irrigant solution, how the irrigant interacts within more complex anatomical environments, and the irrigant’s experience with biofilm resistance.
The clinical study has more viewable specifics that demonstrate the effective combination of mechanical preparation and antibacterial irrigants. They’re observed to significantly enhance endodontic disinfection in comparison to saline irrigation.
A simple technique for more effective irrigant exchange and activation
Clinicians most often use a common irrigation protocol. The irrigant is extruded by gripping the syringe using the index and middle fingers under the wings of the syringe and their thumb over the plunger.
A cleaner method has been proven more effective.
- No special devices are needed
- Alternates positive and negative irrigation
The push-pull technique provides a simple, clean irrigation.
- 1-A small amount of irrigant is extruded
- 2-Thumb placement under the plunger
- 3-Upward push (using thumb) creates negative pressure
- 4-Opposing pressure is used to inject irrigant into the canal
The outcome results in the suction of fluids in the canals. This improves the overall fluid dynamics within the root canal system.
Generally, the push-pull technique keeps the needle stationary while moving the plunger. This enables the liquids to better penetrate the canals.
Specifically, during the negative pressure phase the fluids within the canal return to the syringe and are reactivated. Pathogens are eliminated by the irrigant solution and new irrigants can actively contact the entire dentine surface.
Complete diagrams and detailed explanation of this simple technique are available within the related comprehensive clinical description.
The push-pull technique is used during irrigation with IrriFlex. “Clinical aspects of endodontic disinfection” by dr Francesca Cerutti and dr Riccardo Tonini.
Improved technique support for endodontic disinfection
A polypropylene irrigation needle has been introduced to the market. IrriFlex is an innovation developed by Produits Dentaires SA (Switzerland) aimed at improving the use of the push-pull irrigation technique.
- Back to back side vent design that improves fluid dynamics within the canal
- 30G tip that provides adequate adaptation in curved canals
- Flexibility (beyond that of steel or Ni-Ti) that follows root anatomy through the working length – without blocking
Irrigant is delivered to the most needed locations in the canal. IrriFlex effortlessly dispenses a large volume of solution and allows operational control of tip depth (due to millimetric notches viewable on the cannula shank).
Overall, fluid dynamics are improved throughout the root canal system when using IrriFlex.
Detailed information and diagrams about IrriFlex and its alignment with the push-pull technique are available in the related clinical study.
Contact Produits Dentaires SA for more information about root canal treatment, endodontic disinfection, and related products.