What is an Endodontist?
The word “endodontist” comes from the Greek words “endo,” meaning inside, and “odont,” or tooth. So, as you might be able to guess, an endodontist is someone who specializes in dealing with issues on the inside of one’s teeth – specifically, dental pulp. Teeth are made up of two primary components: the crown and the root. The crown is the white-to-yellow part that you see when you smile at yourself in the mirror. The outer part of the crown is made from enamel, a hard coating that protects the next layer down: the dentine. Dentine is a yellow material that is similar to bone. It holds some nerves that act as an indicator of when something may be wrong and the time has come to go to the dentist. Inside the dentine is the pulp of the tooth. The pulp runs from crown to root and forms the core of the tooth and is full of blood and lymph vessels as well as nerves that relay information from your teeth to your brain. The vital and complex nature of the pulp merits an entire field of study dedicated specifically to it: endodontistry.
While all dentists are trained in endodontic procedures, some endodontic problems can be particularly tricky to both treat and diagnose which is why your dentist may make the decision to refer you to an endodontic specialist.
A Short History:
Endodontistry began in the 17th century. In 1685, Charles Allen wrote the first book solely dedicated to dentistry. Entitled Operator for the Teeth, the book provided the first official statements of how people could better keep their teeth and gums healthy. One such piece of advice included making a form of toothpaste from coral, rosewater, and dragon’s blood that, if used weekly, would prevent tooth decay and gum disease. Though rudimentary, this work provided a launching point for dentistry to be further explored.
French dentist Pierre Fauchard (1678-1761) carried the torch of endodontic discovery after Charles Allen. Considered the founder of modern dentistry, Fauchard published a textbook entitled “Le Chirurgien Dentiste” in 1728. In this publication, Fauchard accurately described dental pulp for the first time and dispelled the idea of the “tooth worm” which has previously been thought of as a cause of toothaches and gum disease.
For five years before publishing the work, Fauchard had 19 medical professionals (six physicians, 12 surgeons, and one dentist) review his work for accuracy. Jean Devaux was the first and most important contributor to the work. Devaux was one of Fauchard’s primary mentors and was a prominent surgeon of the time. By seeking Deveaux's approval of his work, Fauchard helped to solidify dentistry as a distinct medical field that shared knowledge with other, more established fields. The next six physicians who reviewed his text were some of the most prominent members of the medical field of the time, including Philippe Hecquet, Jean-Claude Adrien Helvétius, Jean Baptiste Silva, Antoine De Jussieu, Raymond Jacob Finot, and Antoine Benignus Winslow. In order to further solidify his place as the leader of the emerging dental field, Fauchard sought and received the approval of Laudumiey, surgeon-dentist to His Majesty, Philip V, King of Spain. The approval of such a large number of prominent medical professionals firmly implanted Fauchard as part of their ranks.
Fauchard continued to develop the study endodontistry for the rest of his career. In 1746, he became the first person to describe procedures for removing dental pulp. In doing so, Fauchard inadvertently became one of the first people to describe treatment that can be considered something of a proto-root canal procedure. Such treatment involved leaving a tooth open for several months to drain all pus and abscesses on the tooth. Finally, he would fill the tooth with lead foil in an attempt to prevent the infection from reoccurring. Fauchard also pioneered the modern use of opiates (usually mixed with oils and cloves) for pain relief to keep patients as comfortable as possible during often painful procedures.
His description of this procedure elucidates his understanding of dental anatomy and the causes of toothache and root inflammation and infection. While the process of creating and installing dental fillings was not advanced at this time, Fauchard’s procedure was one of the first to find a way of relieving tooth pain and infection without simply removing the entire tooth.
Endodontic treatment has been in continuous evolution from then until the present. In 1756, German dental surgeon and personal dentist to Frederick the Great, Philip Pfaff, published what he believed to be an improvement to Fauchard’s original method of filling a tooth after removing infected pulp tissue. Instead of filling the entire opening of the tooth with metal directly over the exposed nerves, Pfaff used a method involving the implantation of a rough-cut piece of either gold or lead with a concave base over the top of the tooth that had had pulp removed. This way, he was able to keep the metal from touching the exposed nerve, thus significantly improving patient comfort.
The next year, in 1757, the personal dentist of Louis XV, Bourget, described a method for helping patients who had decaying and/or infected teeth. In this method, Bourget would remove the teeth, fill the root canal with lead or gold, and immediately replant them. He then republished a method for a treatment procedure first described by Arabian physician Avicenna, in which he would remove a problematic tooth, cut the nerve connected to the tooth, and then immediately replant it – thus reducing patient pain but not curing the root of the problem.
After immigrating to the United States from England in 1766, Robert Woofendale became the first man to perform an endodontic procedure in the country. His method of ameliorating a patient’s pain involved opening the tooth and cauterizing the pulp with a hot piece of metal. Instead of implanting a permanent filling like his predecessors had been doing since Fauchard, Woofendale simply stuffed the tooth with cotton. Woofendale also wrote a book entitled Practical Observations on the Human Teeth in which he described that the application of cotton soaked in different chemicals (including cinnamon and clove oil as well as turpentine) to the root of the tooth would eventually destroy the nerves attached to the tooth, thus alleviating some of the pain associated with tooth decay. In addition to these treatments, Woofendale would frequently use unprocessed opium and camphor to cauterize the nerve.
Before the turn of the next century, the practice of cauterization had become more commonplace. Frederick Hirsch, a prominent German dental physician endorsed the application of a diagnostic technique involving tapping teeth until the affected one was found when the patient experienced a jolt of pain. He would then drill into the affected tooth and fill it with lead after repeatedly inserting an extremely hot probe in order to cauterize the nerve.
Around the turn of the next century, dental surgeons began to better understand dental anatomy, which led to more effective treatments. One of the first such discoveries was published by J. B. Gariot in 1805. In his publication entitled Traité des Maladies de la Bouche (Treatment of Oral Ailments), Gariot identified that, in adults, a tooth could remain healthy even if the pulp were destroyed.
Another important development that occurred during this time period was that innovators in dental procedures began to advocate much more heavily for treating teeth in situ rather than removing them, filling the root canals, and then re-implanting them. In light of this, Edward Hudson (an Irishman working in Philadelphia) became the first person to fill a root canal with gold foil without removing the tooth first. He did so using instruments that he had made himself and, according to contemporaneous sources, was exceptionally careful and thorough in every procedure that he performed.
At this time though, sterility was not a priority. The cause of infection was not well known and, before the invention of the dental dam (a sheet of rubber now used to keep a tooth both dry and sterile during a root canal procedure) post-treatment infection was relatively commonplace. For this reason, New York-based endodontist S. C. Barnum became the first dental professional to use a thin sheet of rubber to isolate the affected tooth that he was trying to cure. The increase in sterility that this small addition to the procedure created quickly became a standard part of root canal procedure.
Around the same era, gold foil began to be replaced by a newly-minted compound called gutta-percha. Gutta-percha is a latex-based compound that was originally mixed with other substances such as ground glass and feldspar to create better filling than the gold and lead that were commonly used beforehand. While gold and lead are relatively malleable, it was very difficult for endodontists to provide a complete seal when placing a filling in the tooth. With the advent of gutta-percha based fillings, the material could be heated (to a point just before it burned) and then injected into the tooth. As the substance hardened, it provided a seal that could prevent debris from getting pushed inside the filled cavity and causing an infection to reoccur.
The use of gutta-percha based fillings and dental dams marked the beginning of a deeper understanding of how bacteria affected a patient’s oral health. By the end of the 19th century, filling materials that provided a full seal were commonplace, dental dams were a standard part of the root canal procedure, and antiseptic substances such as camphorated chlorophenol were being used to clean the tooth before treatment, leading to rapid advancements in patient comfort and rapid decreases in recurring infection.
20th Century to Present Day
At the turn of the 20th century, perhaps the most important discovery in the endodontic field was made: the invention of the X-ray. Within the first decade of the 20th century, dentists were able to use X-rays to view the amount of decay present and noninvasively discover the problem thus allowing the dentist to devise a treatment plan without harming the patient.
Around the same time, local anesthetics became more and more commonplace. Dentists had now improved patient care exponentially from even the late 19th century. By 1909, Mayrhofr had identified which specific oral bacteria were the primary cause of root infection, finding that streptococci bacteria were present in 96% of patients who required root canal procedures. Sadly, dentists quickly linked dental health to systemic diseases such as colitis, kidney disease, and gastritis and began a movement promoting the removal of any affected teeth.
Fortunately, some endodontists continued to refine their craft and eventually provided significant enough evidence that decaying teeth did not cause the diseases that earlier dentists had purported them to cause. Largely because of this group of medical professionals, patients can now undergo endodontic procedures and expect success rates approaching 100% – unparalleled in many fields.
Common Endodontic Treatments
The most common type of endodontic procedure is what is known as the root canal. A root canal is a treatment that allows an endodontist to remove the infected or inflamed parts of a tooth without removing the tooth itself – something that many patients prefer over removal of the tooth itself. A root canal becomes necessary when the pulp of the tooth becomes infected or inflamed. This irritation of the pulp can be caused by many different problems, ranging from cracks or chips in the tooth to serious tooth decay and even repeated dental work on the tooth. Below is an image displaying some of the issues that can lead to a root canal being required. If tooth decay, infection, or inflammation is left untreated, these problems can quickly grow to become more serious and lead to tooth abscesses in the root, pulp death, and even bone loss around the tooth. All of these problems can lead to other, more long-term dental issues. For this reason, the importance of endodontistry should not be underestimated.
Modern root canal procedures are almost always done in one to two visits but, depending on the severity of the problem meriting a root canal, a third visit can sometimes be necessary. During the procedure, endodontists almost always use local anesthetics that make the process almost completely painless for the patient.
The first step in a root canal procedure involves doing dental x-rays to survey the damage to the affected tooth. This provides the endodontist with a fairly clear understanding of the type of problems present and allows him or her to come up with a treatment plan for each individual patient’s unique case.
Next, the endodontist will administer a local anesthetic. Depending on whether the affected tooth has an abscess or not, pain may be more or less severe. After the area has been numbed, the endodontist will insert a dental dam, a thin, rubber-like sheet that will keep the tooth free and clear of saliva during the procedure. This will reduce the risk of infection after the treatment and provide the endodontist with a clean space, enabling him or her to treat the tooth as non-invasively as possible.
Once the tooth is cleaned and dried with a dental dam in place, the endodontist will use small dental instruments to remove the decay and infected pulp. The pulp is very important while the tooth is developing, but once the tooth is fully formed, it is not essential. Once the affected pulp is removed, the endodontist will flush the now-empty root canals in order to fully remove any infected or diseased tissue to ensure that none remains that could potentially cause the tooth to become infected again. During this step in the procedure, the root canals may be enlarged and/or reshaped to allow them to be more easily filled at a later point in time. Before the tooth is filled with dental composite (necessary to re-strengthen the tooth since it will be hollow after this step in the root canal procedure), the tooth should be completely cleaned and dried. If the procedure requires multiple visits to complete, the endodontist will place a temporary filling in the crown of the tooth to keep the cleaned root free of debris and will instruct you to avoid chewing on that tooth until the procedure is complete. In the case of a severely infected tooth, the endodontist performing the procedure may decide that it is necessary to put medication inside the now-clean pulp chamber of the tooth and let the tooth drain for several days. In very severe cases where the infection has spread beyond the tooth, it may become necessary for the patient to take general antibiotics.
The next step in a root canal procedure involves filling the pulp chambers and root canals of the tooth with dental composite. First, the root canals will be filled with a substance called “gutta-percha.” It is a thermoplastic material, which means that it can be heated and then shaped to fill the root canals perfectly. The gutta-percha, combined with an adhesive cement, seals the once-infected root canals of the tooth. If the root canals were properly cleaned of infected tissue before sealing, the seal should prevent the root canals from becoming infected again.
Once the root canals are sealed properly, the endodontist will fill the hole in the crown of the tooth that he or she used to access the infected root. If, during the treatment, the endodontist removed so much material that he or she believes the tooth to be unstable, he or she may decide to place a post made of either metal or strong plastic inside the tooth. If deemed necessary, this post would run from the crown through one of the root canals so that the tooth can become adequately strong to withstand the daily stresses inflicted upon it.
After the procedure, the endodontist may make the decision to prescribe an antibiotic with the intention of either removing any residual infection or preventing an infection that might be more likely to occur because of the procedure. Typically, there will be some soreness after the procedure. In most cases, it will last between three days and a week and should be controllable with ibuprofen. Remember, root canals exist as a way of decreasing a patient’s discomfort, not adding to it!
At this point, an endodontist will likely refer you back to a general dentist for a permanent crown filling. This is to ensure that the root canals are properly sealed so that absolutely no debris can get in and potentially cause infection. Within the human mouth there are up to 700 species and 20 billion individual bacteria. If the tooth is not properly and completely sealed, these bacteria can cause serious infections similar to the ones that cause root canals to be necessary in the first place. Because of this, having a general dentist put a permanent crown on the tooth is a critical step in preventing infection after the root canal is completed.
After the procedure is completed, the once-infected or inflamed tooth should look aesthetically pleasing and be either as strong or nearly as strong as it originally was – but now even more protected from infection. If the procedure was done correctly and the patient continues to keep up with basic dental hygiene, the endodontically treated tooth should last just as long as untreated teeth.