Endodontic History

By Bradley H. Gettleman, DDS, MS; Moein Sadrkhani, DDS, MSc; and Laurence D. Johns, DDS, MSD

We must start this article by giving the utmost respect and credit to Dr. James Gutmann.  The simple fact is that in doing our research for this brief synopsis of endodontic history, we found the writings and presentations of Dr. Gutmann to be extremely educational, and it is our opinion that he is the most thorough endodontic historian of our time.

Dr. Gutmann and others agree that there is truly no way to ascertain with complete accuracy how long endodontic treatment has been around.  The word “endodontics” itself comes from the Greek prefix “endo,” meaning “within,” and “odont,” meaning “tooth.  The term endodontics was coined by Dr. Harry B. Johnston.¹ In 1928, his practice was the first practice to be “limited to endodontics”.¹

The first evidence of treatment “within a tooth” dates back to around 200 B.C. when archaeologists discovered a human skull in the northern Negev Israeli desert containing a tooth that had a 2.5 mm bronze wire in it, which was believed to have been used by the Romans as a treatment for infected teeth.² The Romans were also assumed to have invented crowns and dentures.  A few hundred years later, archaeological findings revealed that root canal infections were drained as a method of relieving pain.³ This is thought to have been the main method for the treatment of infected root canals, with the exception of extraction, until around the 1600s.  In 1687, Charles Allen wrote the first book written in English devoted exclusively to dentistry.⁴ In his book, he discussed procedures for transplantation of teeth, “taking out the rotten teeth or stumps and putting in their places some sound ones drawn immediately out of some poor body’s head.”⁵

One of the original theories for the cause of tooth pain was the “tooth-worm” theory.  This theory dates back to the Babylonian times⁴_,  yet this belief in worms as the causative agent of dental caries continued through the late Renaissance.⁶ Specifically, the theory claimed that a tooth worm resided in the hollow portion of a tooth, where it would cause a toothache by gnawing at the structure of the tooth.⁴ One method of driving the worm from within its hiding place in the hollow tooth was to tempt it with honey smeared on the outside of the tooth; this would cause the worm to emerge to eat the honey, at which time it could be plucked from the mouth.⁶ Another common method was to heat henbane seeds with charcoal and have the individual with the tooth of concern inhale the fumes. The plant from which these seeds are taken also has narcotic properties that relieved the tooth pain.⁷

Professor Jacobaens of the University of Copenhagen reported that after he scraped about in a carious tooth, he saw a worm come out, which he put in water and watched as it swam about.⁶ Yet another physician claimed to place rancid oil into a cavity, which enabled him to drive out worms that were an inch and a half in length.⁸ The driving out of these worms was thought to cause a cessation of tooth pain.⁸

A few decades later, in 1700, Anton van Leeuwenhoek, the “father of modern microscopy,” worked with worm-infested cheese in response to receiving worms from the president of the Royal Society of London, the most august scientific body of its day.⁶ While his work did not completely invalidate the “tooth-worm” theory, it definitely did much to lessen its acceptance.  Specifically, Leeuwenhoek attributed tooth pain to pulpal inflammation; however, he did not correctly discuss its etiology.⁶ He incorrectly ascribed the pain to a result of the worm eating away at the tooth, rather than inflammatory action of the bacterial toxins on the dental pulp.⁶ In addition, he claimed that pain reduction was a result of killing the worms with the use of Oyl of Vitriol.⁶ The reality is that the sulfuric acid destroyed any remaining vital nerve tissue in the pulp, which is what most likely led to the reduction of pain.⁶ The use of sulfuric acid was actually practiced to some extent until the end of the nineteenth century.

Nearly thirty years later, in 1729, Pierre Fauchard – known as the father of modern dentistry – wrote his book The Surgeon Dentist. In this book he wrote descriptions not only of pulp cavities and root canals, but also regarding the practice of opening teeth to relieve abscesses and evacuate pus.⁴ He made mention of a few different remedies for relieving tooth pain, one of which was to leave a tooth open for up to three months, after which time he would fill the pulp chamber with lead foil.⁴ Another remedy Fauchard discussed involved rinsing the mouth every morning and also before going to bed with one’s own rinse (urine) immediately after it has been emitted, always provided that the individual not be ill.¹ While these methods seem ludicrous today, they must be viewed in the context of the medical practices and knowledge of that time.  Consider the quantity of diseases in which bloodletting was used as a treatment during that time period.

Finally, the last method of relieving discomfort mentioned by Fauchard is more directly related to endodontic issues as it involves pulp extirpation, or trepanation of the tooth, using a small needle or pin.^1,4  Another common endodontic procedure found its roots in the mid 1700’s when a German dentist discussed the first pulp cap. Specifically, this occurred in 1756 when Dr. Phillip Pfaff, dentist to Frederick the Great, discussed capping exposed pulps using gold foil or lead.^{1, 4, 9, 10} This was done to prevent the exposed nerve from direct contact with the restoration.

While there were many different treatment modalities within endodontic therapy during the late 1700s and early 1800s, a major advance came in 1838 when Edwin Maynard created the first instrument designed specifically for endodontics. He designed this endodontic instrument by modifying a watch spring.^{4, 11} (In addition, he invented the Maynard Rifle, which is what he became most famous for, as his rifle was used by armies all over the world).⁴ A short time later, in 1847, Edwin Truman introduced gutta-percha to the field of dentistry.⁴ Gutta-percha was first used in dentistry as a filling and denture base material⁴_,  and the first individual to popularize the use of gutta-percha as a sole root filling material was G. A. Bowman in 1867.^1,4,12

While there have been many other materials developed and used for the obturation of the root canal system, there is absolutely no question that gutta-percha has stood the “test of time,” probably more so than any other material in dentistry. Through the years, gutta-percha has been found to be useful for many different purposes such as: golf balls (gutties), protection for the hulls of boats, insulation for underwater cables, manufacturing of corks, and surgical instruments, just to name a few of the more popular uses.¹³ There is no question that more obturation materials will continue to be developed and tested; however, at this time, gutta-percha is the most widely accepted material available.                                

Association History

1943 was an extremely important year for endodontics, as a group of individuals met at The Palmer House in Chicago that February to form what was originally called The American Root Therapy Association.  In 1944, the organization’s name formally became The American Association of Endodontists, the name which is still used for the association today.¹⁴ The Palmer House was also the location for the creation of iconic American dessert “the brownie” back in 1893.  The first journal dedicated to endodontics was The Journal of Endodontia, published in 1946.  Next, the American Association of Endodontists was incorporated in 1955 with 568 members, and the American Board of Endodontics was formed.¹⁴ In 1967, The American Dental Association approved Endodontics as a specialty.¹⁴ The first editor of The Journal of Endodontics was Worth B. Gregory, with the first JOE being published in 1975.¹⁴  

On May 15th of 1989 the American Association of Endodontists application for re-recognition was denied, which shocked our specialty since AAE had been planning the application for re‐recognition as far back as 1987 when the association formed a Task Force on Recertification.  Drastic times needed serious action; with the leadership of Dr. Gerald Dietz Sr. and related committees, the ADA House of Delegates unanimously supported the re-recognition application on November 8, 1989.¹⁵

Association Leadership

The first president of The American Association of Endodontists was Dr. W. Clyde Davis of Nebraska, who was named president in 1943.  In 2004, Dr. Sandra Madison became the first female president of the association.

References

1. Ingle JI, Bakland LF, Baumgartner JC: Ingle’s Endodontics. 6^th Hamilton, Ontario: BC Decker, 2008. pp 36-85.
2. Harris, J: The History of the Root Canal. East Coast Endodontics, Sep 10, 2014.
3. Hotz, R: Ancient Root Canal Dug Up. New York Times News Service. August 9, 1985.
4. Cruse, WP, Bellizi, R: A historic review of endodontics, 1689-1963, part 1. J Endod 6:495, 1980.
5. Costich, ER, et al: Plantation of teeth: a review of the literature. NY State Dental Journal. 29:3-13, 1963.
6. Ring, ME: Anton van Leeuwenhoek and the tooth-worm. JADA 83:999-1001, 1971.
7. Nunez, K: Debunking the Myth of Tooth Worms and Other Cavity Causes. Healthline. June 29, 2020.
8. Guerini, V: A history of dentistry from the most ancient times until the end of the eighteenth century. Philadelphia, Lea & Febiger, 1909, p232.
9. Dammaschke, T: The history of pulp capping. Journal of the history of Dentistry. Spring 2008;56(1):9-23.
10. Franke OC. Capping the living pulp: from Phillip Pfaff to John Wessler. Bulletin of the History of Dentistry 1971; 19:17-31.
11. Castellucci, A: Endodontics. 2004; pp 2-5.
12. Grossman LI: Root Canal Therapy. 3^rd Philadelphia, Pennsylvania: Lea & Febiger; 1950.
13. Vishwanath V, Rao HM: Gutta-percha in endodontics – A comprehensive of material science. Journal of Conservative Dentistry. 22(3): 216-222, 2019.
14. Milas VB: A History of The American Association of Endodontists 1943-1968. January 1, 1968.
15. AAE website. https://www.aae.org/specialty/wp-content/uploads/sites/2/2017/07/2_history_43_93_manuscript.pdf