Traditionally, pulp sensibility tests have helped to form the basis of clinical endodontic diagnoses. During an examination, the clinician performs a number of tests to elicit a response from the patient, informing whether they may have clinical signs of pulpitis/pulp necrosis. Whilst these tests have been used for many years, and do have a place in modern endodontics, they are often subjective, which can make the results difficult to measure. As such, clinicians should consider the impacts that digital technology could have on endodontic diagnostics, and how and when to implement these testing methods.
Traditional pulp testing: benefits and challenges
Pulp testing is traditionally used to assess the neural response of the dental pulp. These tests include temperature, electric, and percussion tests, each of which reveal different information about the pulp, and have their own strengths and weaknesses. For the best results, clinicians should first test a control tooth, which they believe to be healthy, to ascertain a normal response, in order to recognise an abnormal response for each patient.[i]
According to the British Endodontic Society’s (BES) Guide to Good Endodontic Practice, cold testing should be used as a first line evaluation.[ii] Cold testing is now most often performed using a refrigerant spray, with ethyl chloride, dichlorodifluoromethane, and ice used historically. The cold temperature causes the dentinal tubule fluid to contract, resulting in negative pressure. The results of a cold test indicate both pulp vitality as well as the condition of the pulp. Patients should alert the clinician if they feel a sensation during this test, recording both the intensity and duration of the response. In this type of test, a positive response indicates vitality, whilst a negative response may indicate pulp necrosis in some cases.[iii]
Electric pulp testing is carried out using an electric pulp tester (EPT) which flows a high frequency electrical current from the probe tip through the tooth. This current stimulates viable fibers in the tooth, triggering a tingling sensation. Whilst a positive response indicates vital pulp tissue, it does not signal pulpal health. A negative result, however, does reveal pulp necrosis.[iv]
Percussion tests can be used to accurately identify the effected tooth, where the disease has progressed apically to affect the periodontal ligament. Clinicians should tap gently on the incisal or occlusal surface of the tooth using the blunt end of an instrument. This requires gentle force, and the patient should inform the clinician of any sensitivity. A positive response does not necessarily indicate endodontic disease, with trauma and periodontal disease also resulting in sensitivity.[v]
Digital imaging to form a diagnosis
Digital imaging is now well established in endodontic diagnosis, offering lower exposure doses compared to conventional radiographs. Current radiographic imaging software enhances images to aid clinicians in diagnosis, treatment planning, and visualisation of root canals during treatment. Cone beam computed tomography (CBCT) may also be used to support endodontic workflows where appropriate, but only after conventional radiographs have been taken. CBCT images are able to produce an accurate 3D reconstruction of the anatomy, enabling clinicians to more easily understand the structure of the root canals.[vi] Radiographic images are essential for successful endodontic treatment, enabling practitioners to plan their path through the root canals, and identify the effected pulp.
Guided endodontics
Guided endodontics is a technique which is still evolving. Its use is applicable over multiple treatment types but is useful, in particular, when accessing and locating root canals, microsurgical endodontics, and in endodontic retreatments.[vii]
Static guided endodontics requires a CBCT image and dental impression to create a surgical guide to cover the teeth in the area. Drill holes can be designed to allow direct access to specific root canals. It is thought that static guided endodontics results in shorter treatment times for patients, and improves accuracy and safety when compared to conventional treatment. However, time is required to create the guides, and they are only effective for straight canals.[viii]
Dynamic guided endodontics uses CBCT images with the help of a camera connected to a dynamic navigation system. This technique is more ergonomic, and allows adjustments and repositioning to be made in real time. As such, it is accurate as it does not include design errors, and can be used on multi rooted teeth. Clinicians require additional training to be competent in using this technique for the best results.[ix]
Looking to the future
The implementation of digital technology in the endodontic field so far is promising, enabling clinicians to more efficiently and more accurately diagnose and treat endodontic infections. Looking to the future, we can anticipate the introduction of more digital tools which will further improve endodontic workflows and diagnostic procedures, as well as improve the longevity of treatment results.
Author: Alyn Morgan
Alyn Morgan qualified from the University of Leeds School of Dentistry in 1995. He worked in general dental practice for 12 years and undertook his postgraduate training in Endodontics at the Eastman Dental Institute, where he was awarded an MSc with Distinction in 2009. He worked as the Director of Endodontic CPD at the Eastman for several years and is currently Endodontic Teaching Lead at the Leeds Dental Institute, whilst maintaining a specialist endodontic practice at U Dentistry in Ilkley. He has presented well over 200 hands-on courses in endodontics, lectured nationally and internationally as a keynote speaker at numerous conferences and study days and acted as a key opinion leader and adviser to several multi-national dental companies. He is the immediate Past President of the British Endodontic Society, and the co-founder and CEO of a spin-out company from the University of Leeds, Mimetrik Solutions. The company develops innovative clinician-led solutions in the field of digital dentistry, , and to date has attracted over £3.5m in grant funding and investment.
[i] The journal of multidisciplinary care decisions in dentistry. Principles of endodontic diagnosis. Accessed May 24. https://decisionsindentistry.com/article/principles-endodontic-diagnosis/
[ii] British Endodontic Society. Guide to good endodontic practice. Accessed May 24. https://britishendodonticsociety.org.uk/news/39/a_guide_to_good_endodontic_practice/
[iii] The journal of multidisciplinary care decisions in dentistry. Principles of endodontic diagnosis. Accessed May 24. https://decisionsindentistry.com/article/principles-endodontic-diagnosis/
[iv] The journal of multidisciplinary care decisions in dentistry. Principles of endodontic diagnosis. Accessed May 24. https://decisionsindentistry.com/article/principles-endodontic-diagnosis/
[v] The journal of multidisciplinary care decisions in dentistry. Principles of endodontic diagnosis. Accessed May 24. https://decisionsindentistry.com/article/principles-endodontic-diagnosis/
[vi] British Endodontic Society. Guide to good endodontic practice. Accessed May 24. https://britishendodonticsociety.org.uk/news/39/a_guide_to_good_endodontic_practice/
[vii] Kulinkovych-Levchuk K, Pecci-Lloret MP, Castelo-Baz P, Pecci-Lloret MR, Oñate-Sánchez RE. Guided Endodontics: A Literature Review. Int J Environ Res Public Health. 2022 Oct 26;19(21):13900. doi: 10.3390/ijerph192113900. PMID: 36360780; PMCID: PMC9657991.
[viii] Kulinkovych-Levchuk K, Pecci-Lloret MP, Castelo-Baz P, Pecci-Lloret MR, Oñate-Sánchez RE. Guided Endodontics: A Literature Review. Int J Environ Res Public Health. 2022 Oct 26;19(21):13900. doi: 10.3390/ijerph192113900. PMID: 36360780; PMCID: PMC9657991.
[ix] Kulinkovych-Levchuk K, Pecci-Lloret MP, Castelo-Baz P, Pecci-Lloret MR, Oñate-Sánchez RE. Guided Endodontics: A Literature Review. Int J Environ Res Public Health. 2022 Oct 26;19(21):13900. doi: 10.3390/ijerph192113900. PMID: 36360780; PMCID: PMC9657991.
