Endodontic Diagnosis

In this episode of PodMD, experienced specialist endodontist Dr Christine Premdas-Rogers will be discussing the topic of endodontic diganosis, including when a patient should or should not be treated, how a patient might typically present for endodontic therapy, the risks associated with the treatment, when a dentist should refer and more.

  • Transcript
    Please note this is a machine generated transcription and may contain some errors.
    *As always, all in this PODMD podcast is intended for health professionals and the comments are of a general nature. Information given is not intended as specific medical advice pertaining to any given patient. If you have a clinical issue with one of your patients please seek appropriate advice from a colleague with expertise in the area.

    Today I’d like to welcome to the PodMd studio Dr Christine Premdas-Rogers

    Dr Rogers is an experienced specialist endodontist based in Sydney. Christine has worked in general practice, hospital service and as a specialist academic and clinical lecturer in both Australia and the United Kingdom throughout her career. She has a strong focus on educating her patients about the endodontic process as she understands that endodontic care can be nerve-racking for many patients.

    Today, we’ll be discussing the topic of endodontic diagnosis.

    *We do hope you enjoy this podcast but please remember that the advice here is of a general nature and is not intended as specific advice about a given patient. The views and opinions expressed in this podcast are those of the doctor, not PodMD.
    If you do have a patient on whom you require specific advice, then please seek advice from a colleague with appropriate expertise in that area.

    Christine, thanks for talking with us on Pod MD today.

    Christine: Thank you for having me.

    Question 1
    The topic of today’s discussion is endodontic diagnosis. Can you describe for our listeners when they should treat or not treat?

    Christine: Yes, certainly the first thing is we need a diagnosis, so that means it’s the usual systematic collection of information, including a description from our patient of symptoms, their experience, seeing previous dental history for the tooth or area, which is easier if it’s actually one of our regular patients, their medical history, the timeline of the pain, and any aggravating or stimulating factors and clinical and radio graphic examination, it’s important that we do undertake some pulp sensibility tests for the tooth that we suspect or the patient suspects as the cause of the pain and for adjacent and or depending on what teeth patient has the contralateral tooth.

    A rule of thumb is that there should be two or more signs or symptoms to support our diagnosis and decision to initiate treatment on a tooth, if we’re in doubt, the patient may have to wait to be reassessed at a later date or can we consider an onward referral.We shouldn’t be tempted to treat the tooth if our examination findings are inconclusive or conflicting, and that actually happens more often than not. So once the causative tooth is identified, and the decision regarding whether to treat or not relies on the case assessment.

    And a good example of a case assessment form is that from the American Association of endodontics, which grades cases into a degree of difficulty, either minimal, moderate, or high difficulty, and the kind of things it questions and encourages us to look at is has, for instance, the teeth previously had root canal treatment. From the radiographs are there is there any evidence of any procedural errors? Are the short fillings present? Can the patient tolerate dental down? If it’s a regular patient will know if they have a strong gag reflex and any anxiety about dental work being carried out in the mouth, particularly towards the posterior teeth, how wide they can comfortably open their mouth and the location and orientation of the tooth.

    From the radiographs we need to assess the curvature of the roots, if there are any unusual features, such as an additional root, can we actually see the root canals? And if there’s an associated apical radiolucent lesion, how big is it and does it affect any adjacent teeth or anatomical structures? So when considering all of these factors, if they fall outside our experience or comfort zone, then we can make a decision as to whether or not we want to treat the tooth. And maybe we consider referral.

    Question 2
    How would a patient who requires endodontic therapy typically present?

    Christine: Well, effectively a patient may just pitch up for a consultation appointment at routine examination and not be aware of any problem at all. So symptoms can range from no knowledge, no experience of pain, to acute pain with all grades in between. One of the recent changes in endodontic diagnosis has been the state of the pulp. So we used to use terms such as reversible pulpitis, meaning that the inflammation could resolve following appropriate interventions such as removal of tooth decay and placing restoration. And irreversible pulpitis where we assess the tooth and the patient symptoms and felt that that indicated a level of pulpal information that would not resolve from simple conservative treatment, but those terms have now changed to reflect possibly more of the histological status of the pulp that we imagine is there, so reversible is now termed mild and moderate, and irreversible it is termed severe pulpitis.

    Patients presenting with acute pain typically presents with some form of anxiety or distress. They usually haven’t slept and will report that, they’ve usually tried a whole range of analgesics and not found an effective way to manage the pain experienced. Sometimes they can present shipping cold water which they find gets relief. They can describe the pain as being triggered by thermal stimuli of foods that they eat or drink, or spontaneous onset. However, as the inflammation may not have spread to the apical tissues, the tooth may not give an abnormal response to percussion of the tooth or palpation of the tissues around the apex, and so effectively in our examination we’re relying on pulp sensibility, testing and the history.

    If we’ve got a situation where pulp necrosis has occurred, then the pulp will not respond to any pulp sensibility tests, and that’s a definite finding and typically can be observed following traumatic injury. Sometimes the canals can be infected and then apical Periodontitis may be symptomatic and the tooth will respond to percussion and palpation in an abnormal sense to the adjacent teeth and may also be visible radiographically and that AIDS diagnosis.

    An acute apical Abscess is fairly obvious. It’s an inflammatory response to the pulp infection and the necrosis with the spreading say lighters puss formation. Sometimes the patient may have a temperature and lymph adenopathy the most serious of these would be those associated with lower posterior molar teeth and we have a spreading Cellulitis across the neck where there’s always the risk of embarrassment of the airway and then in addition to our normal adjunct of analgesics and all antibiotics, they may actually need referral for intravenous antibiotics.

    Question 3
    What are the risks associated with endodontic therapy?

    Christine: So endodontic therapy is actually fairly predictable and very successful. But it is a technical procedure and effectively we’re using fine instruments in narrow confined spaces, so the most prevalent risk would be that of file fracture. Occasionally we can have perforation and that’s to do with the orientation of our access cavity sometimes and the orientation of the tooth and just in trying to trace very fine calcified narrow canals and occasionally our irrigation fluids can leak into the surrounding supporting soft and hard tissues.

    However, although we need to advise our patients of these potential risks as part of our discussion for informed consent, the incidence is actually about 3%, so it’s fairly low and with care during treatment for the length of our measurements with the use of instrumentation and how deep we put our irrigation needles and the shape of the irrigation needle tips into the root canal system and using single use usage of files, we can do a lot to minimise the occurrence of these risks.

    Question 4
    What are the endodontic treatment options for a tooth which has failing endodontic therapy and a post retained core?

    Christine: OK, so the options are either non-surgical retreatment, which will involve the replacement of the post and crown or root end microsurgery leaving the post and crown in situ and so the decision really depends on whether it’s an anterior or posterior tooth. Whether if it’s an anterior tooth, the aesthetics of the crown, and if the patient is happy with the crown, the actual width and length and construct of the post and the restorability of the remaining two structure.

    The patients willingness for multiple appointments, particularly if we are doing a retreatment and replacing the Crown and post and associated costs. If there are any apical radiolucent lesions and we’re considering root end microsurgery and that’s the patients also preferred preference and then we need to know the size of that and it’s position and in particularly related to adjacent anatomical structures.

    Question 5
    What is the success rate for endodontic therapy?

    Christine: The success rate is really high. It partly depends on the tooth that’s actually being treated, so our highest success rates are for teeth with vital pulps, and that will be in excess of 90%, and that’s achievable by both dentists in general practise as well as specialists. If we have to deal with infected canals and apical parodontitis, then the size of the lesion is indicative of associated apical parodontitis and in research studies, we’ve noticed a small drop in success rate, so we’d be quoting patients 70 to 80%.

    Retreatment actually falls in the same group, but really the success rate improves if we can identify before we start treatment the reasons for failure and whether we can actually improve on that technically, or whether actually it’s going to be a difficult challenge. And so the kind of things we’re looking at are: was rubber down used during the previous treatment? How many visits, whether the dentist had explained for their only difficulty locating canals if there’s any missed root canal anatomy, that type of thing.

    Question 6
    When should a dentist refer?

    Christine: So when the diagnosis is not clear and suggestive of oral facial pain, and then the second opinion is always worthwhile getting at that stage. Sadly we do see many patients still presenting with multiple treatments where they’ve been complaining of pain and have believed it to be associated with one or more of their teeth. And in order to provide relief, the dentist has initiated treatment, but then find that the patient returns complaining of symptoms that do represent some form of pulp critic symptoms and then initiate treatment on another tooth. So really, we do need a second opinion if we find that we’re in that situation and we want to prevent carrying out unnecessary treatments.

    If we have a concern that a satisfactory result may not be achievable, such as difficult access to the tooth, and typically that could be something like an upper second molar tooth which can be rotate, well the crown can be rotated [inaudible] and therefore difficult to get two and also difficult for the patient to stay open wide enough to accommodate the use of instruments in the roots in those teeth.
    If the access is through a crown or bridge, the angulation of the structure may be different to the actual original position and morphology of the tooth and so therefore drilling a hole through the occlusal access of a cast restoration created by technician, which bears no relationship to the morphology the tooth can be misleading and we can end up creating an access cavity which unduly weakens the tooth, and sometimes in the worst case scenario can actually cause a perforation at the cervical area of dentine.

    If we have difficulty in isolating the tooth, if radiographically, we notice that there’s a result of defects present in the root structure or the crown of the tooth. If we’re dealing with immature developing tooth that’s had a traumatic injury, but the truth is not responding to the initial endodontic therapy, and we can see signs, for instance, of increasing root surface inflammatory resorption and if we see radiographically that the canals are not easily visible and the pulp chambers calcified and so the canals then calcified canals can be difficult and time consuming and if the root curvature is greater than 30 degrees then that is also technically challenging, so those might be situations where you’d consider referring.

    Question 7
    What role does the dentist play in the treatment of the tooth?

    Christine: So all dentists are trained to undertake endodontic treatment. In which case you’re responsible for the endodontic treatment and restorability of the tooth and the overall care for that treatment plan. If the patient is referred, then the patient is returned to the referring dentist for provision of the Coronial Seal, which actually can be more important than the endodontic treatment itself and have indicated a cuttable coverage restoration after the root canal treatment.

    Concluding Question
    Thank you for your time here today in the PodMD studio. To sum up for us, could you please identify the three key take home messages from today’s podcast?

    Christine: Yeah, the first one will be diagnosis. If it’s not clear which tooth needs treatment, then don’t treat until there’s enough collaborative evidence to suggest that we should be.

    Second point would be to assess the restorability of the tooth and usually all the clinician who has the job of restoring it post treatment and sometimes it’s very difficult as an endodontist to assess your abilities and you are the better judge so please do have a good assessment of the restorability before referring.

    And in the case of your undertaking, root canal treatment, and there’s a procedural accident, and timing is a concern, such as with hypochlorites accident. Then do call a local endodontists for advice at that time, most will return your call as much of urgency to assist you.

    Thanks for your time and the insights you’ve provided.

    Christine: Thank you for having me

*As always, all in this PODMD podcast is intended for health professionals and the comments are of a general nature. Information given is not intended as specific medical advice pertaining to any given patient. If you have a clinical issue with one of your patients please seek appropriate advice from a colleague with expertise in the area.