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A. Greene Vardiman Black This versatile genius was born on a farm near Winchester, Illinois in 1836. He loved nature and knowledge but did not like school very much. His later life would suggest that he learned much too fast to tolerate the inhibiting effects of the structured classroom -- an odd paradox since he became a world-renowned teacher. At the age of nineteen he went to Clayton, Illinois to serve a preceptorship under his brother, Tom, a practicing physician. He spent a couple of years with Tom and then was attracted to dentistry. After a few weeks with a rather mediocre dentist, Dr. J. C. Speers, in Mt. Sterling, Illinois, Black decided he was ready to open his own office. He married and started a dental practice in Winchester, near his home. He was the first and only dentist in the county. Shortly after that, he volunteered for service in the Civil War. He injured his knees soon after joining the army and spent several months in the hospital. He apparently never saw combat. After the war, Black decided to go into partnership with an older dentist, J. C. Cox, in the larger city of jacksonville, Illinois. Jacksonville had several educational institutions including the first college in the state, a public library, literary union, philharmonic society, and a number of well-educated physicians and dentists. Black had the opportunity to perform dissections and increase his knowledge of human anatomy. He was asked. to discuss the ether spray for lbcal anesthesia to the local medical society. Then he was asked to return and he presented papers on "Diagnosis of Kidney Disease", "Inflammation", "Theory of Sight", "Typhoid and Scarlet Fever" and others. In 1869 he presented his first paper to the Illinois State Dental Society on "Gold Foil". Black organized a Chemistry Club which promptly elected him to be the teacher and seminar leader. This gave him the opportunity to learn in the most effective way for him, through teaching. He was so unusually intelligent that having his class filled with other educated physicians and dentists only supplied sufficient challenge and direction for his studies. Later he formed a Microscope Club for the same reason. He obtained one of the first microscopes in Illinois and became the de facto consulting pathologist for the region. The story is told that an ophthalmologist once brought Black a small foreign body he had removed from a patient's eye. Black at the time was treating a patient and told the ophthalmologist to leave the specimen on the table. A few days later the ophthalmologist returned while Black was inserting a gold foil restoration, but the specimen had been analyzed and identified by him as a specific gland from the leg of a potato bug which had much the same irritant effect as Spanish Fly. He was quite surprised that the ophthalmologist had not recognized it. Black had taught himself Latin and French but much of the scientific literature at that time, especially in cellular pathology, was coming from Germany. He went to a local merchant who was German and arranged to buy him supper and cigars every Thursday night for some instruction in German. Before long he was able to get the German scientific journals directly and read them without having to wait for translations. Black was married and had several children. He was an excellent musician and member of the Philharmonic Society, the Dramatic Club, Grand Master of a Mason's Lodge, Public Library Committee, Literary Society, and Chairman of the Third Ward Republican Club for three years. In 1870, he was offered a professorship in Oral Pathology at Missouri Dental College. During the next ten years he spent two days a week in St. Louis Missouri at the dental school and the rest of his time in Chicago. During this time, in addition to his private practice, teaching and studying, he published approximately a hundred scientific articles. During this period, the state of Illinois announced that they would begin licensing physicians in 1878. Since Black had actually engaged in medical practice prior to that time he could have registered to continue without taking the examination, but he chose to be one of the first to take the examination. Thirty- four candidates took the first examination. Only half of them passed with the required score of over 80% specified by the board, but G. V. Black had no problem passing it the first time and was licensed to practice medicine. He never listed himself as a physician or attempted to build a practice in general medicine, but apparently he wanted whatever opportunities and freedoms such a credential might carry to enhance his dental career. He was such an enthusiastic scholar that perhaps he just couldn't pass up the opportunity to show himself how well he could do. That same year (1878), after he had been a professor at Missouri Dental College for eight years, the school decided to award this man, who had never attended a medical or dental school, a D.D.S. Degree. His degrees were all honorary. In 1884 he was given an M.D. Degree by the Chicago Medical College; in 1892, an Sc.D. from Illinois College; in 1898, an L.L.D. from Northwestern and in 1915 another Sc.D. from the University of Pennsylvania. In 1880 he quit teaching at Missouri. In 1883 he was teaching again, this time at the Chicago College of Dental Surgery. In 1884, he published his first full length book, The Formation of Poisons by Micro-organisms. At about this time, Dr. Black began his research on silver amalgam. He had to invent and either build or have built much of the equipment because of the newness of the field. He also served during this time on the Illinois State Board of Dental Examiners. In 1891, he left Chicago College and began teaching at Northwestern University Dental School. Dr. Black was a meticulous researcher, repeating every experiment at least three times. The problems with amalgams were tremendous. He investigated the effects of moisture and drying, different methods of mixing, mixing times, and many alloy formulas. He calculated the force of mastication on the teeth with every conceivable hardness of food. He analyzed expansion and contraction of the metals, shear strength, compressive strength, corrosion and a host of other factors and related them all to each other. In 1895 he had succeeded in analyzing every requirement of an adequate filling material and developed a balance of ingredients for a silver alloy with a specific percentage of mercury to produce the first satisfactory amalgam fillings. He prepared a series of articles to publish his results. At this point he was approached by friends who asked him if he realized that by patenting his process, keeping it a secret and going into the manufacturing business he could become a millionaire. Of course he realized this but said it offered no temptation. He was financially secure and had an exciting career that really couldn't be measured in monitary value. He offered to present a series of lectures on the metallurgical parts of his research to any manufacturers who wanted to pay $100.00 tuition, after which he said the full report of his research would be published to the world. In 1895, his series of articles began in Dental Cosmos under the general title of ÒAn Investigation of the Physical Characters of the Human Teeth in Relation to Their Diseases and to the Practical Dental Operations, together with the Physical Characters of Filling Materials.Ó The series was concurrently published in dental journals in virtually every civilized country of the world. From the beginning of dental history there had never been a good long-lasting treatment to repair the damage of dental caries and prevent further caries that was available at a cost that was reasonable to the general public. Silver amalgam was not only a relatively inexpensive material (lead had been used for over 100 years) but it required a fraction of the operating time, cutting the cost to the patient dramatically. This was the most significant event up to that time to bring a high quality of conservative dental treatment to the general population. In 1897, C. V. Black became Dean of Northwestern University Dental School. He died in 1915. Over his life he made many, many contributions in all aspects of dental science, dental practice, and dental education; and there is certainly not room to list them here. Carl E. Black and Bessie M. Black wrote biographies of G. V. Black and his son Arthur D. Black (also a famous dental educator) in a book titled From Pioneer to Scientist, Bruce Publishing Co., St. Paul, Minn., 1940. A statue of G. V. Black stands in Lincoln Park in Chicago as an inspiration to those interested in the life and work of this great man. B. Operative Dentistry 1. Gold Foil Dr. Arthur's discovery, and several other recommendations in the gold foil operation, were published for the whole profession to benefit from. This seems like a simple discovery, as many do, but it meant a tremendous improvement in the success of gold foil restorations. 2. Dry Operative Field 3. Rubber Dam In the 1870's some improvements were made replacing the saliva pump with a saliva ejector that worked off the principle of suction produced by having the ejector connected to the water supply. 4. Matrices In the Dental Cosmos for April, 1871, Dr. Louis Jack described the first matrices designed to provide a form for proximal fillings. They were double wedge-shaped pieces of steel with the thick edges to be located cervically and buccally. In addition to the basic shape, they were hollowed dut in a variety of shapes and sizes to approximate the shapes of proximal contours. A tremendous number of them were required to fit the range of sizes and shapes of teeth. Immediately other dentists began introducing several types of thin metal matrix bands to be attached to the teeth in a number of clever ways with strings, clamps, and screws. 5. Rotary Cutting Instruments
Improvements in the first type of drill may have been made prior to 1850, but none appear in writing. Between 1850 and 1905 several inventions by dentists provided mechanical advantages and some automatic rotation. The best known of these is the one invented by Charles Merry in 1858. It had a flexible joint coupling to provide an angle for the working end. The rotary end was connected by a flexible wound wire to a fairly large driving wheel with a handle to turn it. The first improvement of the third type (with automatic rotation by foot-power) was G. F. Green's pneumatic engine in 1868. It was an air-driven hand piece! The air power was provided by foot bellows. The air went through a rubber tube to the hand piece. This exciting idea was reinvented in the late 1950's using compressed air and is the standard instrument today. Green's instrument was nowhere near as efficient as the famous Morrison foot pedal engine introduced in 1871. S. S. White improved on the Morrison Engine in 1875. A number of these instruments are in modern museums, and one is in the Dean's office at the Oregon Health Sciences University School of Dentistry. The fourth type of dental engine, with an automatic source of power was actually invented by G. F. Green between 1856 and 1858 -- at least 10 years before his pneumatic drill -- but he was too far ahead of his time. He called his instrument the Òelectrical burning engineÓ. His design for a handpiece driven by electricity was excellent. The problems were that electric motors were in their infancy, there was no available source of electric current and electric batteries were difficult to obtain and maintain. Around the turn of the century when electric power became available, several manufacturers simply picked up on the concept Green had described decades before and electric dental engines became standard. While all this was occurring some dentists tried water pressure -- an idea again tried in the 1950's, apparently without any better results than the first time it was tried. Edmond Noyes in his History of Operative Dentistry (1909) says he knew one dentist who "made for himself a little steam engine which drove his dental engine and laboratory lathe, the exhaust being made noiseless and inoffensive by being carried through a pipe into a pail of water". Clever -- if it worked. While all these technical improvements were being made, G. V. Black was outlining the principles of scientific cavity preparation and conservative restorative principles. There is no room here to cover all the many additional improvements in filling materials, instruments and techniques but, hopefully, this brief discussion illustrates the general trend in the development of operative dentistry in the latter half of the 19th century. Dental Coverage
C. Removable Prosthodontics S. S. White began manufacturing porcelain teeth in 1844. That same year, Dr. John Allen of Cincinnati, Ohio, began working on an all-porcelain denture with a platinum base that would restore not only the lost teeth but also the lost alveolar ridge, form and appearance of the gums. It took him seven years. He mastered the problems of shrinkage and color and produced one of the most admirably esthetic and functional dentures ever made -- known as the "continuous gum" denture. The problem was that these dentures cost between $2,000 and $5,000 a set -- in the year 1855! All dentures were costly. The standard techniques using gold or silver bases cost several hundred dollars a set -- still too expensive for most people. Of the people who could afford dentures, some could afford the continuous gum denture, but something was needed for the rest of the people. Several materials like Celluloid were being tried as denture bases, but they all had problems. Celluloid, for instance, tended to turn green and smell bad. In 1854 Dr. Thomas W. Evans of Paris made a denture for Charles Goodyear, Sr., using a hard rubber base (vulcanite) invented by the Goodyear family. In 1855, Charles Goodyear, Jr. was granted a patent on the use of vulcanite rubber as a denture base. Vulcanite turned out to provide a very good denture base at very low cost. Sometimes vulcanite was used in conjunction with metal bases but this really was not necessary. Porcelain teeth with holes or pins forretention could be set into the rubber before processing. Various shades of veneer rubber could be used to give the appearance of gum tissue. The material was well-tolerated by the oral tissues and sets were sometimes made for as little as $5.00. D. Local Anesthesia The discovery of surgical anesthesia stimulated some practitioners to think about some method of local anesthesia. In 1848, James Arnott suggested a small pig's bladder half-filled with water to be placed over the teeth and gums. Then some crushed ice was to be added along with salt to lower the freezing point; it was then to be held in position for fifteen to twenty minutes. It wasn't a very useful technique. In 1856, J. B. Francis invented a technique for extracting teeth using forceps attached to an electric battery. The patient held the positive pole in his or her hand. When the forceps touched the tooth, the circuit was completed and the tooth was quickly extracted. This was not a huge success either. In 1884, Sigmund Freud invited an ophthalmologist friend to do some work with him investigating the effects of cocaine. Freud was primarily interested in the neurological and psychological effects of cocaine. He left for a short vacation and while he was gone, his friend, Carl Koller, with his assistant, tried dropping cocaine into the eyes of animals and found that it produced local anesthesia. Koller presented his discovery in a paper on September 15, 1884. Freud had a burning desire to become famous, which had not yet occurred by that time. He wrote that it really bothered him that he missed out on either being a discoverer or co-discoverer of local anesthesia, but he never tried to take any of the credit from his friend, whom he referred to in later years as Dr. Coca Koller. Two months after Koller's discovery, an American surgeon, William Halsted, tried injecting the drug close to a nerve trunk to see if it would "block" the nerve conduction. Koller and other Europeans had only used cocaine anesthesia by topical application on mucous membranes. The first nerve blocked was the inferior alveolar (dental) nerve. Halsted experimented almost entirely on himself, blocking one nerve after another. Just as Horace Wells had developed an addiction to chloroform by self-experimentation, Halsted became addicted to cocaine. He was made aware of the problem and made a valiant fight to break the addiction -- apparently with success. Cocaine was a dangerous anesthetic and dentists had a difficult time getting profound anesthesia over a sufficiently long time without producing serious side effects. One approach to solving this problem was the invention of high pressure syringes using snug-fitting needles inserted into either bone or dentin. A high degree of mechanical or chemical pressure was used to force the solution into a confined area of hard tissue. In 1901 Heinrich Braun discovered the vasoconstricting property of epinephrine and suggested its use with cocaine to prolong the anesthesia and slow the rate of absorption. In 1904, Einhorn and his associates discovered exactly what they had been trying to find, a synthetic local anesthetic without the side effects of cocaine: procaine (Novocaine). E.
Women in Dentistry While Dr. Emiline Jones (as she was known in her community) was beginning to break the "all-male" barrier in Connecticut, a school teacher named Lucy Hobbs was searching the State of Ohio for a dentist who would allow a woman to serve a preceptorship in dentistry. One courageous dentist, Dr. Samuel Wardle, finally accepted her on the same basis as his other students. Shortly after completing her preceptorship she applied for admission to Ohio College of Dental Surgery, one of only three existing dental schools at that time. With a college preparation for teaching and the completion of a preceptorship from a well-respected dentist, she was obviously better qualified than most of the students applying in 1861, but she was promptly rejected. At Dr. Wardle's advice she started practice without the advantage of a dental degree (not yet a common or necessary credential). After trying three different cities, she finally built a very successful practice in McCrego, Iowa. In 1865, by means of special resolutions, she was elected to membership in the Iowa State Dental Society. One of the resolutions passed stated that dentistry ". . . has nothing in its pursuits foreign to the instincts of women". Now, four years after her first application, Lucy Hobbs applied again for admission to the Ohio Dental College. Finally she gained admission. This prompted Dr. George T. Barker to write in the Dental Times an editorial entitled "Dental Surgery -- should women practice it?" He concluded that "the very form and structure of a woman unfits her for its duties" and that the creator ". . . in His wisdom, did not see fit to endow the female of the species with the necessary strength which the practice of dentistry requires.Ó Dr. Barker went on to propose an amendment to the National Dental Association "to allow none but males to be eligible from local societies to the convention". (Dr. Hobbs had been elected as a delegate from Iowa that year.) The proposed amendment was not adopted. Dr. Lucy Hobbs next opened an office in Chicago where she met and married James M. Taylor. She proceeded to train her bridegroom in a dentalpreceptorship. The couple then moved to Lawrence, Kansas where they lived and practiced dentistry for many years. In 1867 another woman, Henrietta Hirschfield, applied for admission to Pennsylvania College of Dental Surgery. She was rejected, but like Lucy Hobbs, she persevered and finally gained admission; but the anatomy professor steadfastly refused to admit a female to his course, and she was required to attend the Women's Medical College for her instruction in anatomy. In 1868, Dr. James Truman, a faculty member who had supported Miss Hirschfield's request for admission proposed a resolution to the Board of Trustees favoring the acceptance of women students. It was tabled, but after years of debate finally passed. It stated in part "That the advancing spirit of the age and the just right of women require that they shall be admitted to medical and dental education . . ." In 1872 three female students were admitted. A petition was sent from the male students to the faculty demanding that the females be ejected. The faculty agreed to comply with the request! Dr. James Truman objected and took the matter to the Board of Trustees who referred the question to a committee. News of the controversy reached the press who championed the women's cause. It took until spring (March 31, 1873) for the committee to conclude that since the schoolÕs charter did not prohibit the enterance of women, and the faculty had allowed them to matriculate and accepted their fees, they were obligated to readmit the women and allow them to complete their studies. These examples reflect the opposition of many male dentists toward women entering the profession in the mid-1800Õs. Obviously, any woman attempting to enter the profession then had to be willing to oppose enormous odds, but it should be recognized also that a few courageous men in the profession were willing to face the ridicule and the opposition of their colleagues to fight for women's rights. It is fortunate that throughout history there have always been a few individuals willing to fight for a cause simply because they believed in it. For many years, the percentage of women in dentistry stayed around 2% in the United States. For some reason it was seen as a male occupation although in many other countries of the world it was common to find percentages of women dentists between 25% and 50% and some were much higher. Since 1970, the number of female dental students has been climbing in the U.S. but now seems to have leveled off at about 20-30%. F. W. D. Miller and the Etiology of
Dental Caries Other dentists, as we have seen, came to the conclusion that food remaining in the mouth putrified and somehow caused the teeth to decay. Parmly (1819) suggested that caries was externally caused by some as yet unidentified chemical agent. Some even went so far as to suggest that it was acids that caused decay. Ficinus, a German physician, observed microorganisms taken from carious cavities and implied that somehow they caused decay but did not suggest how. Prior to 1889 no one had supplied an adequate theory with experimental proof. The person who finally did that, producing one of history's outstanding pieces of scientific research, was W. D. Miller. Willoughby Dayton Miller was born in Alexandria, Ohio on August 1, 1853. He received an A.B. Degree from the University of Michigan in 1875 and then went to Scotland to do graduate work in physics, mathematics and natural philosophy. Then he went to Germany to study physics at the University of Berlin. There he met some American dentists who were studying in Europe. He became interested in dentistry and at their suggestion decided to pursue a dental career. He began studying in the office of one of these dentists, Dr. Frank Abbott. Then he returned to the United States and in 1879 received his D.D.S. Degree from the University of Pennsylvania Dental School. He then returned to Germany, married Dr. Abbott's daughter and accepted an appointment in 1884 to teach operative dentistry at the University of Berlin. He continued to study and upon taking the German ÒRigorosumÓ examination was awarded the M.D. Degree. During the 1880's he studied bacteriology under the famous Dr. Robert Koch. During that decade he did his exhaustive research on the etiology of dental caries and wrote one of the classics of dental literature, Microorganisms of the Human Mouth, published in Germany in 1889 and the United States in 1890. Miller's research was exhaustive. It had to be to answer all the wide range of theories and arguments at that time regarding caries. He began by producing caries in sterile teeth outside the mouth using pure strains of specific microorganisms to disprove the inflammation theory. The facts proven by his long series of careful experiments can be summarized as follows: 1) Various kinds of foods (bread, sugar, but not meat) mixed with saliva and incubated at 37¡ C could decalcify the entire crown of a tooth. 2) Several types of oral microorganisms (at least 30 were isolated) could produce enough acid to cause dental caries. 3) Lactic acid was an identifiable product in carbohydrate-saliva incubation mixtures. 4) Different microorganisms (filamentous, long and short bacilli and cocci) invade carious dentin. He concluded that no one single organism caused caries. He felt that the process consisted of one stage in enamel -- simply the dissolution of enamel by acid from acidogenic microorganisms. Caries in dentin he believed consisted of two stages:
He summarized his findings in a much more thorough list of eighteen propositions which are all considered valid today. W. D. Miller and G. V. Black had been friends for many years. Black had also done significant research in oral microbiology and coined the term dental plaque. Around the turn of the century the two men visited in New York. They both had the vision at that time to recognize that they had lived to see the beginning of a new age of scientific preventive dentistry. Dental Coverage
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