Steps In Endodontic Treatment

Successful endodontics depends on efficient protocols. Here is a basic checklist to go through while performing an endodontic treatment:

Anesthesia Administration

Local Anesthesia with Adrenaline: Administer a good amount of local anesthetic to numb the affected tooth and surrounding tissues. This ensures the patient remains comfortable and pain-free during the procedure.

• • For maxillary & mandibular anterior teeth – buccal infiltration
  • For maxillary premolars & molars – buccal and palatal infiltration
  • For mandibular premolars & molars – inferior alveolar nerve (IAN) block + sometimes buccal infiltration

Hot tooth:

• If infiltration does not suffice, consider giving a nerve block.
• Intra ligamentary infiltration works wonders in hot tooth.
• Sometimes, an intrapulpal administration may also be necessary after access opening in a hot tooth.
• Articaine, available only in 2 ml vials and to be used in self aspirating syringes, is the best aesthetic agent for such cases.

Rubber Dam Application

Isolation of the Tooth: Places a rubber dam (a thin sheet of latex or silicone) around the tooth to isolate it from saliva. This ensures a clean working environment and prevents contamination during the procedure. MiniDam can also work, and so does a frequently changed cotton roll when in humble working conditions.

Access Opening

• • Creating an Opening: Drill a small opening in the crown of the tooth to access the pulp chamber. This step allows the dentist to remove the infected or damaged pulp and clean the root canals.
  • For anterior teeth – take access palatally/lingually
  • For posterior teeth – take access occlusally

Cleaning and Shaping the Root Canals

• • Removal of Infected Pulp: Remove the infected pulp tissue using hand files. The pulp tissue is carefully extracted from the pulp chamber and each root canal.
  • Working Length Determination in Endodontics: Working length (WL) refers to the distance from a reference point (usually the tooth’s incisal or occlusal surface) to the apical terminus (the tip of the root) of the canal system, which is the point where the root canal instrumentation and cleaning should ideally stop. Accurate determination of working length is crucial to ensuring proper root canal treatment. The goal is to clean and shape the entire canal, but without over-instrumenting or under-instrumenting.

Methods for Working Length Determination:

Radiographic Method:

• Initial X-ray: An initial radiograph is taken after the access opening to determine the canal’s general shape and length.
• Intraoperative X-ray: After initial instrumentation, a second X-ray is taken to verify the WL, with a file placed in the canal to the determined length.

Electronic Apex Locators (EAL): These devices use electrical impedance to detect the position of the apical foramen, providing real-time feedback on the working length. They are often used in combination with radiographs to improve accuracy.

Tactile Method (Manual): This involves using a hand file to reach the apex, determining resistance or the feeling of “apical stop.” However, it is less accurate than the radiographic or electronic methods and can sometimes result in over-instrumentation.

Combination of Methods: A combination of radiographs and apex locators offers a more accurate and reliable result. EALs are often used in conjunction with radiographs to minimize errors.

Importance of Accurate Working Length:

• • Prevents Over-Instrumentation: By stopping at the correct working length, over-instrumentation and damage to the periapical tissues are minimized.
  • Ensures Complete Cleaning and Shaping: The canal can be cleaned and shaped up to the apical region, ensuring effective removal of bacteria and debris.
  • Minimizes Post-Treatment Discomfort: Incorrect working length can result in unnecessary irritation of the periapical tissues, leading to post-treatment discomfort or failure.

Biomechanics Preparation (BMP)

Shaping the Canals: Shape the canals using a series of increasingly larger files. This step also helps clean the canals and remove debris.

The shaping of root canals is an essential part of root canal therapy, aimed at cleaning and enlarging the canal system to facilitate disinfection and obturation (filling). Two commonly used techniques for shaping the canal are the Step-Back Technique and the Step-Up Technique. These techniques involve different approaches to instrument the root canal while maintaining the desired taper and avoiding over-instrumentation or under-instrumentation.

1. Step-Back Technique

The Step-Back Technique is a widely used method for root canal preparation. It involves progressively enlarging the root canal starting from the working length and moving back toward the orifice.

Procedure:

• •  Initial Preparation: Begin by cleaning the coronal part of the canal and establishing the working length (WL) using the previously determined working length measurement.
  • Coronal Enlargement: Use a large file (usually a #10 or #15 K-file) to enlarge the coronal portion of the canal. This step helps in gaining better access to the rest of the canal, making instrumentation easier.
  • Progressive Enlargement: Begin using progressively larger files, and systematically work from the apex back toward the orifice, making sure to stop at a slightly shorter length with each successive file. This creates a taper in the canal, where the apical portion is narrower than the coronal portion.
  • Step Back Sequence:The clinician moves the file back in increments of 1 to 2 mm (depending on the canal anatomy) while maintaining the working length in the apical region. Each new file should be larger than the last, gradually stepping back toward the orifice of the canal.
  • Final Enlargement: The final file used should be large enough to ensure proper cleaning of the entire canal system, and should ideally reach the working length or slightly short of it.

Advantages of Step-Back Technique:

• • Controlled Taper: The gradual decrease in file size from coronal to apical helps create a smooth, well-shaped canal.
  • Reduces Risk of Perforations: By using smaller files in the apical region, there is less risk of causing perforations or over-instrumentation.
  • Suitable for Simple Canal Shapes: Works well for relatively straight canals.

Disadvantages of Step-Back Technique:

• • Time-Consuming: Requires multiple file changes, which can extend the time of the procedure.
  • Risk of Instrument Fracture: As you are stepping back multiple times, there is a potential risk for instrument breakage if the instruments are not used carefully.

2. Step-Up Technique

The Step-Up Technique is an alternative approach where the canal is first prepared with smaller files, and progressively larger files are used to increase the size and taper of the canal, starting from the coronal portion.

Procedure:

• • Initial Preparation: Like the Step-Back Technique, the working length is established, and the canal is initially cleaned of debris.
  • Coronal Enlargement: Use a small file to clean and shape the coronal portion of the canal. This step prepares the canal for easier access to deeper sections.
  • Step-Up Enlargement: The clinician starts with a small file and progressively uses larger files, moving toward the working length. The process involves gradually increasing the size of the instruments as you approach the apex, ensuring that the canal is properly tapered from the coronal to the apical end.
  • Final Enlargement: The largest file used should allow for sufficient space for the irrigants to reach the apex and ensure adequate cleaning.

Advantages of Step-Up Technique:

• • More Conservative: This technique tends to be more conservative than the Step-Back technique because it doesn’t aggressively enlarge the canal in the apical region.
  • Decreased Risk of Over-Instrumentation: It is less likely to cause over-instrumentation of the apical part of the canal, as the files are gradually increased to the appropriate size.

Disadvantages of Step-Up Technique:

• • Risk of Leaving Debris: Since the canal is not enlarged from the apex toward the orifice, there is a greater risk of leaving debris, particularly in the apical area.
  • Requires More Attention to Detail: Careful attention is needed to avoid creating ledges or forcing files into the canal, especially in curved canals.

Irrigation

The canals are frequently irrigated with an antiseptic solution (often sodium hypochlorite) to disinfect and flush out any remaining tissue or bacteria. This is critical to prevent reinfection.

Drying the Root Canals

After cleaning, dry the root canals with sterile paper points. This is important to ensure that there is no moisture before the next step of sealing.

Filling the Root Canals

• • Filling Material: Once the canals are cleaned and dried, fill it up with the biocompatible root filling material called gutta-percha. Gutta-percha is a rubber-like material that helps seal the root canal and prevent bacteria from re-entering.
  • The gutta-percha is inserted into the canal, and a sealer is applied to fill any small spaces. This prevents the growth of bacteria inside the canals.

Sealing the Access Opening

• • Temporary or Permanent Filling: After filling the root canals, seal the opening created to access the pulp with a temporary or permanent filling. The temporary filling may be used for the first visit if multiple appointments are needed, while a permanent filling is used once the root canal procedure is complete.

Restoration of the Tooth

• • Core Build-Up: If the tooth is significantly weakened due to extensive decay, a core buildup may be needed. This involves restoring the tooth structure with a special material to ensure it can support a crown.
  • Crown Placement: Most teeth that undergo root canal treatment require a crown to restore their strength and function. A crown is placed on top of the tooth to protect it and provide a natural appearance.

Follow-Up Appointment

• • After the root canal and crown are placed, schedule a follow-up appointment to check for any complications, such as signs of infection or discomfort.
  • In some cases, you may have to take additional X-rays to ensure that the root canal filling is properly sealed.

Additional Considerations

• • Multiple Appointments: Root canal treatment may require more than one visit if the infection is severe or if there are multiple roots in the tooth. In such cases, place a temporary filling after the first visit and schedule a follow-up appointment for the final filling and crown.
  • Antibiotics and Pain Relief: Prescribe antibiotics if there is an infection or recommend pain medications to manage any discomfort following the procedure.

Conclusion

By removing the infected or damaged pulp, cleaning and disinfecting the root canals, and sealing the tooth, RCT helps prevent further infection and alleviates pain. With proper care, a tooth that has undergone root canal treatment can last for many years, providing a long-term solution to oral health issues.