Managing extremely curved root canals

13 August 2023

Mark Allen outlines the challenges clinicians face when treating patients with complex anatomy.

The aim of endodontic treatment is to remove the infected dental pulp to restore or maintain the function and appearance of the natural tooth. Ideally, the root canals are prepared in a way which respects the root canal anatomy, preserving the shape and form throughout the entire canal. However, sometimes, root canals are more curved than usual, making conservative preparation more difficult. Cases like these can require additional planning and preparation, and it is important that clinicians have the instruments and expertise necessary before tackling cases with extremely curved canals.

Managing curved canals

Even when adequate planning is undertaken using radiographs, the root canal morphology may not always be as simple as anticipated. Extremely curved canals present the clinician with challenges, restricting the ways in which the canal can be prepared. Without adequate preparation, extreme curvature can affect the prognosis. Because of this, pre-operative assessments should include a focus on the root canal anatomy – enabling clinicians to establish the complexity, curvature, and radius of the root canals. This will allow more adequate preparation prior to treatment. By having a clear idea of the root canal anatomy, treatment will become more predictable, and the occurrence of errors and excessive removal of tooth structure will be reduced.

Reliable diagnosis and treatment

Predictability and reliability are key aspects of endodontic treatment. Because of this, diagnostic imaging is crucial for accurate treatment planning. 3D imaging is preferable in determining root canal curvature as curves that present buccolingually may not be visible on a 2D radiograph, leading to misinterpretation of the data. CBCT is an excellent tool here, providing clinicians with the ability to anticipate the exact root canal structure from all angles. This lowers the risk of false negative outcomes. It may also enable the clinician to detect any other pathologies not visible through an intraoral exam or with 2D imaging methods.

By gaining a clear image of the clinical situation, adequate planning is possible, allowing the clinician to effectively prepare an extremely curved canal. There are a number of methods a clinician might implement to manage curved root canals. These include the balanced force technique, step back technique, step down technique, standardised technique and the anti-curvature technique. Each of these has its benefits and challenges, but it is important that clinicians take care during the hand instrumentation phase to avoid ledge formation, as well as the creation of zip, transportation and file fracture.

Building trust with patients

Having established a clear understanding of the patient’s canal anatomy, produce and explain the treatment plan to the patient so that they know they are in very capable hands. Conversely, if the treatment plan were to change suddenly due to unanticipated curved root canals, the patient may feel less confident and lose trust in the abilities of their clinician. Because of this, it is important to have the equipment and instruments needed to complete effective endodontic treatment, despite potential root canal curvature.

To complete a successful treatment of a curved root canal, it is useful for clinicians to have versatile instruments available at all times. This ensures they are always ready to treat cases with complex anatomy efficiently. This is essential for building and maintaining a trusting relationship with patients. Using reliable instruments will also reduce the likelihood of accidental perforation of the root canal walls, allowing the clinician to accurately judge and prepare for the shape of the root canal. This is key for predictable endodontic treatment.

In complex cases, the ability to rely on your instruments is essential. HyFlex EDM files from Coltene facilitate the preparation of extremely curved canals without compromising on preservation of the root canal anatomy. HyFlex EDM files high fracture resistance and flexibility make them ideal for tackling complex cases, and they deliver fast preparation with high cutting efficiency and a reduced number of files. HyFlex EDM files can be pre-bent, another crucial advantage which further enables effective treatment in extremely curved canals – avoiding the creation of steps.

Making an accurate diagnosis is key to successful endodontic treatment. By planning effectively, based on accurate assessments, clinicians are able to carry out predictable treatment with successful outcomes. This helps to lower the risk to the patient and maintain the trusting relationship, which is essential for patient satisfaction. Reliability is crucial here, which is why it is vital to use instruments which facilitate superior treatment even in complex cases. Build an armamentarium which facilitates versatility and supports the treatment of complex root canals – allowing you to provide your patients with outstanding endodontic treatment.


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References available on request.