Technology is Rapidly Changing the Face of Dentistry
In the 11th century, long before the first comprehensive scientific textbook on dentistry, Fauchard’s Le Chirurgien Dentiste, was published in 1728, dentistry was practiced by a variety of craftsmen, primarily barbers, but also wig makers, bloodletters, goldsmiths, and blacksmiths, among others. Yet despite their lack of formal, academic training, these medieval practitioners possessed a distinctive skillset and used specialized instruments to remove, repair, and replace the hardest tissue in the body.
The prominence of the early dental practitioner dates back to 1092 when Pope Cyril II of Alexandria decreed that priests and monks would have a new grooming style, a shaven face and a unique hairstyle. The Pope invited razor et minutor (barbers and blood removers) to take up the task. As a result, barbers and the instruments they used — razor, lance, and scissors — became part of a budding surgical profession and barber-surgeons were created. The use of a scalpel was not far behind.
Priests could read medical texts and became physicians but they were not allowed to have blood on their hands and so performed no invasive interventions. The prohibition against bloodletting and surgery by physician-priests began in 1163 when Pope Alexander III, as part of the Council of Tour, declared: “ecclesia abhorret a sanguine.” Loosely translated it meant, “shedding of blood is incompatible with the cleric’s holy duty to God.” This was the beginning of the separation of physicians from surgeons, a division that lasted for approximately 800 years. The separation is still visible in the names of venerable institutions that include the words “College of Physicians and Surgeons,” as, for example, in Columbia University College of Physicians and Surgeons and the Royal College of Physicians and Surgeons of Canada.
In the early medieval pecking order, barber-surgeons were ranked not only as inferior to formally educated physicians, but, in medieval France, they were ranked further. The term “Surgeons of the Long Robe” referred to those with some academic training to distinguish them from barber-surgeons, or “Surgeons of the Short Robe.” The academically-trained surgeons were situated socially between physician-priests at the top and the lowly barber-surgeons. Yet the low status of the barber-surgeons did not prevent kings and queens from using them in military ground battles and on long naval voyages, where they gained experience treating wounded soldiers and sailors. Necessity is the mother of invention and barber-surgeons, who were practical and innovative, responded by making technical advances that went on to have a major impact on society.
The first and arguably most prominent of these was Ambroise Paré (1510-1590), a barber-surgeon to four French kings, who replaced hot oil cauterization of bleeding wounds with ligature. Prior to Paré’s innovation, hot boiling oil poured in a wound, without anesthesia, was thought to “purge” gunshot wounds of the presumed poisonous nature of the gunpowder. Many of the soldiers died of shock and sepsis following such excruciating treatment. Paré, known as “the gentle surgeon,” invented the use of a soothing wound dressing, thereby reducing pain caused by the hot oil and greatly enhancing wound healing and survival. Paré, a Huguenot, was so valuable that his Catholic king, Charles IX, hid him in his bedchamber’s closet during the night of August 24, 1572, the date of the “St. Bartholomew massacre,” to save him from the murderous rampage. Paré lived to be 80, leading a productive life, adopting new surgical techniques, and developing extraction instruments that we still use today. His ligature of blood vessels and wound dressing technique changed surgery forever.
Pierre Fauchard (1678-1761), considered the “father of modern dentistry,” began as a naval surgeon apprentice to Alexandre Poteleret, surgeon-in-chief to his Majesty’s ship in Louis XIV’s court. Fauchard witnessed the ravaging effect of scurvy on sailors and in particular on their gums. From this experience and the fact that a lack of funds prevented him from completing formal training in surgery, Fauchard decided to pursue dentistry, which did not require a costly apprenticeship. His experience with Poteleret was more extensive than many practicing dentists had at the time. He became a dental surgeon, one of 21 dentists in Paris at the time. His seminal book, “Le Chirurgien Dentiste,” is a compilation of scientific knowledge of dentistry at the turn of the 18th century. The manuscript has many original elements, such as the use of carved ivory obturators with attached teeth for cleft palate, a description of tooth dysplasia, new prosthodontic devices for replacement of missing teeth, and innovation in the type and use of dental instruments.
Dr. Horace Wells, a dentist from Connecticut, who was responsible for the use of anesthesia in dentistry, had an impact on both medicine and dentistry. He was the first patient to have a tooth extracted under nitrous oxide (NO) anesthesia.
Following a demonstration the day before during which Wells observed the use of NO for public entertainment, one of the performers, who was under the influence of the anesthetic, seemed unaware of an open flesh wound on his leg and of pain from a self-inflicted wound he had incurred while prancing around on stage. Wells instantly realized the implications for painless surgery and arranged for a demonstration in his practice. The next day, Dec 11, 1844, Dr. John Rigg, a local periodontist, performed an extraction on Wells. Gardner Quincy Colton, the itinerant entertainer who brought NO to town, was at hand to administer the anesthetic. The extraction was painless even though the subsequent public demonstration at Massachusetts General Hospital was a dismal failure. That doomed the use of NO in general surgery. However, present at that failed demonstration was a former student and partner of Wells,’ a part-time medical student and adventurer, William Morton, who subsequently went on to use ether as a surgical anesthetic. On October 16, 1846, the first public demonstration at Massachusetts General Hospital, dubbed “ether day,” with Morton present, was a rousing success. It set the stage for painless surgery in the US and around the world.
Subsequent technological advances were more incremental and less impactful on other branches of medicine. Nevertheless, these advances helped to make dentistry a highly respected and sought-after profession.
They include the invention of amalgam as a material for tooth restoration. Two Englishmen, the Crawcour brothers, introduced it in the US in 1833, amid considerable animosity and professional jealousy from colleagues. Amalgam contained shavings of silver coins, tin, and mercury mixed into a paste. It has been the dental restoration material of choice for the past 180 years, and only recently has it become displaced by advances in highly fracture resistant aesthetic bonding materials.
In the mid-19th century, dentures to replace missing teeth were made of ivory, hippopotamus or human bone, or metal (brass or lead). Starting in 1851 they were replaced by a new technology, vulcanized rubber, invented by Charles Goodyear, an American, who succeeded in hardening the resin of the rubber tree. An American dentist émigré to Paris, Thomas Evans, first used it as a denture base in 1848.
Caries investigation was significantly advanced when a German-educated, American scientist, Dr. Willoughby D. Miller, described the Acid Dissolution Theory in 1890. Until that time, caries, the most common infectious disease affecting humans, was thought to be caused by worms. Using experimental approaches learned from Dr. Robert Koch, a German physician and pioneering microbiologist, Miller reproduced caries in an environment that simulated the oral cavity while working at the Free University of Berlin. Miller, who is recognized as the first oral microbiologist, was influenced to become a dentist by Dr. Frank P. Abbott, dean of New York College of Dentistry from 1911 to 1924, who was Miller’s partner in Berlin and his father-in-law.
The dental drill was a major breakthrough in speeding up removal of decayed tissue. The use of a drill on teeth dates back 6,500 years. The use of modern dental drills started with George F. Green, an American dentist who in 1868 invented the foot pedal-operated pneumatic drill and seven years later patented the electric drill.
The pneumatic high-speed air rotor drill developed by Dr. John Patrick Walsh in 1949 in New Zealand followed the invention of the electric slow-speed drill. Dr. John Borden commercialized the high-speed drill in the 1950s in the US.
The toothbrush has ancient roots. But the invention of the commercial mass-produced toothbrush is attributed to the Englishman William Addis, who in 1770 came up with the idea while in prison. Using swine bristles thread through holes at the ends of a carved cattle bone, he created the first toothbrush prototype. Once released from prison, he started to mass-produce it. The first three-row bristle toothbrush was invented in 1844 and the first nylon toothbrush was commercialized by DuPont in 1938. The first electric toothbrush was created in 1939.
Toothpaste was invented in 1850. The first toothpaste was based on a formulation of powder or pumice. The invention of modern toothpaste is attributed to the American dentist Dr. Washington Wentworth Sheffield, who came up with the patent in 1878. He is also credited with placing it into collapsible tubes. The idea came to him while in France observing the tubes used by Parisian painters.
One of the most significant advances in modern dentistry derives from the use of dental sealants to prevent dental decay. In the mid-1960s, Drs. Michael Buonocore and E. I. Cueto introduced the first commercial sealant. The product was based on Dr. Buonocore’s work on the development of materials to prevent occlusal caries in posterior teeth. In 1974, Drs. J.W. McLean and A. D. Wilson introduced the glass ionomer cement currently used for fissure sealants.
The discovery of the role that fluoride plays in caries prevention is an achievement that the CDC ranks among the 10 greatest public health advances of the 20th century. Fluoride research had its beginning in 1901, when a young dental school graduate, Frederick McKay, left the East Coast to open a dental practice in Colorado Springs, Colorado. When he arrived, McKay was astounded to find scores of residents with grotesque brown stains on their teeth and began research, in collaboration with renowned dental researcher Dr. G.V. Black, that led to recognition of fluoride’s preventive capabilities, and, 30 years later, to the knowledge that water-borne fluoride can prevent cavities.
Under the leadership of Dr. H. Trendley Dean at the NIH, the first major public water fluoridation project began in in Grand Rapids, Michigan, in 1944. The project, which lasted 15 years, showed that the caries rate among Grand Rapids children born after fluoride was added to the water supply dropped more than 60 percent. As a result of their efforts, McKay, Dean, and others helped to transform dentistry into a prevention-oriented profession.
Dental implants made of shells (alloplasts) were used by the Mayan civilization in 600 AD. The origin of modern titanium dental implants goes back to the late 1940s and early 1950s but their success was uneven. Dr. Per-Ingvar Brånemark developed the first scientifically documented, successful implant system in 1965.
Digital dentistry refers to a wide scope of technologies and devices — introduced in the past several decades — that incorporate digital or computer-controlled components in contrast to mechanical or electrical devices alone. The digital technologies that might be used in the dental office include CAD/CAM (computer-assisted design, computer-assisted manufacture), cone beam CT, digital X-rays, intra-oral camera, dental lasers, and optical scanners, among them.
One of the most recent technological advances is Invisalign®, a system that creates a series of computer-generated clear plastic orthodontic realigners to correct slight malocclusions. Invisalign® “democratized” orthodontics by making the system available to general practitioners. The 1997 invention is attributed to Zia Chishti and Kelsey Wirth.
More recently, a new technology developed at the NYU College of Dentistry has been shown to significantly decrease the amount of time required for a patient to wear braces. The process is called micro-osteoperforation (popularly known as “faster braces”), which involves poking small holes into the patient’s gums using a special plastic drill called a Propel. The controlled injury allows porous bone tissue to form, and, as a result, braces can move the teeth faster. The NYU team that developed this technology, introduced in 2013, was led by Drs. Cristina Teixeira and Mani Alikhani.
No list of technological advances can be complete without discussing advances in dental education. In 1926, as part of a series of studies on professional education in the US funded by the Carnegie Foundation for the Advancement of Teaching, Dr. William J. Gies published a landmark report that established the importance of dentistry as a healing science and an essential component of higher education in the health professions. Dental Education in the United States and Canada, known as the Gies Report, followed a similar report, the Flexner Report of 1910, that reformed medical education. As a result of the Gies Report, all dental schools became part of research universities and adopted a four-year, science-based education, thus ensuring recognition of dentistry as a learned profession.
These are but a few examples in the long and distinguished history of discoveries, technological innovations, and transformations in the stature of the profession that have made dentistry a progressive force for improved public health. Today, dental treatment for caries and periodontal disease is moving into a period of fewer invasive and more preventive interventions. The availability of ever more information, smart technology, know-how, and non-invasive treatments will continue to advance the profession’s momentum by making it easier, faster, better, and more enjoyable for patients.
Technology in Dentistry, Through the Ages. Article compliments of NYU Dentistry and authored by Andrew I. Spielman, DMD, PhD Professor of Basic Science & Craniofacial Biology; Associate Dean for Academic Affairs.