WHERE TO START THE TROUBLESHOOTING WHEN YOUR ROOT CANAL TREATMENT FAILS?
It has been proven through the years that root canal treatment if done right can truly be a minimally invasive treatment that can save our patient’s tooth. It is one of those dental treatments that can literally save the tooth from being extracted and enable us to preserve the natural tooth structure in our patient’s mouth to still be functional for many years ahead. However, we all know that the success of a root canal treatment depends on how well we were able to implement the proper obturation of the root canal and seal whether coronal or apical the tooth being treated. The coronal and/or apical seal are critical to prevent microleakage or reinfection of the canal. While the obturation process if not done correctly can increase the risk of a flare-up and infection.
The most challenging part of doing root canal procedure is our lack or no-direct visual capability while we are doing the treatment. Thus, we are very much dependent on our radiographs, sense of feel during enlargement procedure, our endodontic system we use or if we have the financial capability, equipment that can enhance our visual acumen such as microscope, loupe and/or CBCT scans. However, even with the best gadgets and systems, the success of RCT highly depends on the implementation of our protocols and ability as dentist. The root canal treatment doesn’t only ends in addressing the canal but up to making sure that we protect what we did. So, on this post DMD cEnter would like to discuss the usual suspects why we end up having a failed case after we did the root canal treatment to our patient.
We generally have a guide of the numbers of canal a specific tooth has. But, sometimes there are instances that the teeth may have more canals than what we anticipated, thus, it is a common error that we can miss a canal during endodontic treatment especially if we are relying on the 2D dimension of periapical x-rays. Such as molars that have three roots may have as many as four canals and some may even have small accessory canals. The failure arises when we, as dentists, cannot create adequate access and make it difficult for us to locate properly the accessory canals, if present. On this condition, if left untreated, bacteria will proliferate on these canals which may result of your patient feeling pain and re-infection may develop into a dental abscess. So, the inability to treat all the canals is one of the causes that leads to endodontic failure.
A canal that’s obstructed will make it difficult for us to reach and thoroughly clean the entire canal. The following are some of the obstructions that may hinder you in fully treating the canal and are generally iatrogenic in cause:
➢ Pulp stones
➢ Broken Instruments
➢ Calcification of Canals due to Age or other Contributing Disease
The endodontic files especially nickel-titanium and are used in rotary device tends to get fractured in the canals when the dentist is unconcerned with the cavity preparation and guidelines of their use. This commonly happens on a curved canals especially if the endodontic files is re-used more than it is suggested to or the rotary handpiece or devices is used in speed more than it is supposed to be. As consequence, the instrument may break inside the root canal. Retrieval of the broken instrument depends on the location of the breakage inside the canal and the size of the broken instrument. If the broken instrument is quite large and located in the upper 2/3 part of the canal that’s accessible, retrieving it will be possible. However, if the broken instrument is small and more on the apical portion of the canal, then, the decision of whether it’s still safe to remove it or not lies on us. If not, then, the general course of action is to leave the broken instrument at its location and become part of the root filling material during the obturation. It must be noted, though, that leaving a broken instrument inside the canal lowers the prognosis of the success of the RCT and it is also important that the broken instrument did NOT went out the confines of the root canal and did not perforate the apex of the root and extending outside of it. If the latter exists, it becomes pertinent that the broken instrument must be removed through apicoectomy or surgery.
If the root canal treated tooth is fractured, the affected tooth may develop a fissure or fracture deep beneath the gums, thus it is impossible to fully seal the canal. This allows for the possibility of an infection that leads to increased sensitivity, pain, and the need for re-treatment. On this given situation, the kind and severity of fracture must be assess well if RCT is still possible to do in long term effect.
PERSISTENT BACTERIAL INFECTION
The microorganism that thrives inside the canal may create a persistent microbiological infection. The improper debridement of the canal may lead to recurrency of the pain inside the tooth. Bacteria harbored in root canal areas such as isthmuses, dentinal tubules and ramifications can sometimes evade disinfection. This propagates inflammation and reinfection inside the canals. Thus, the importance of thorough debridement cannot be over emphasized which includes the proper choice of irrigating solutions used.
IMPROPER ENDODONTIC APICAL | CORONAL SEAL
A well-sealed endodontic restoration is essential after the completion of obturation as it would prevent the habitation of any microorganisms, which are present in the environment of the oral cavity. A leak inside a seal is a huge factor in endodontic failure due to microbiological persistence. Seepage of fluids is likely to occur if seal is not properly established. This can perpetuate inflammation anytime. An endodontically treated tooth should be evaluated clinically as well as radiographically for its root canal treatment to be deemed successful.
We know that majority of us find root canal therapy a pain to do so as there are so many unknowns and the solutions given to us to remedy it creates more confusion for us to decide which one is the best to use as well as the safest. Having said that, it is an undeniable fact that root canal therapy even if it is a bane for us, as dentists, to do, it is a boom for our patients because we do get to save their natural tooth if we do this treatment right. For us, if you feel you cannot do the RCT properly whether for lack of knowledge, confidence or equipment, then, it is best to refer the case to a colleague you trust who can do the job right. But, if you can, then, be mindful of the main goal which is to save the tooth and not make it worse later. Always remember that the objective of root canal treatment is to remove intracanal infection and prevent the canal from reinfection by creating a suitable environment for the healing of the tooth. Truly follow the protocols especially the use of rubber dam for isolation, invest on your further continuing education in Endodontics and choose wisely what instruments, diagnostics and gadgets you would like to use to make the chances of your RCT treatment’s success higher.
Dr. Bryan Anduiza - Writer
Dr. Mary Jean Villanueva - Writer | Editor
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