Rubber Dentures For The Masses

In April of 1796, when George Washington sat for his portrait before Gilbert Stuart, the President was trying without much success to adjust to a new set of false teeth. He had recently lost his only remaining natural tooth, a lower left premolar, which he had insisted on keeping long after all his others had been lost or extracted. Washington’s attachment to this last tooth was not sentimental. A lifetime of suffering from dental ailments had taught him a good deal about the mechanics of the mouth, and he knew that this lone premolar was the last anchor with which he might secure a working set of artificial teeth. Without this tooth, the coil springs universally used in those days to hold dentures in place against the gums would exert a much stronger outward pressure, thrusting the lower denture forward and resulting in the projection of his lower lip.

Neither Washington nor Stuart was pleased with the President’s appearance. The new dentures caused his lower lip to bulge a lot more than the old ones had, contrasting with the neatly defined inward curve evident in pictures of the younger, handsomer Washington. His upper lip now looked retracted and sunken. But without these dentures Washington’s appearance was much worse. With nothing to keep his jaws apart, his mouth collapsed altogether, rounding the President’s normally elongated face. So to help compensate for the lower lip’s bulge, Stuart stuffed cotton behind Washington’s upper lip. His portrait of history’s most famous malocclusion now appears on every U.S. dollar bill.

These dentures were produced by John Greenwood (1760–1819), a pioneer in oral hygiene and one of the first dentists to advocate brushing the teeth. Although Washington soon discarded them in favor of a better-fitting set, they exemplified the state of the dental art at the time. The trouble for Washington and his many toothless contemporaries was that the art of making false teeth had not significantly progressed in more than five hundred years.

A few years after George Washington had such trouble with his dentures, the first step toward a solution came from James Gardette (1756–1831), a French-born Philadelphia dentist who had been professionally trained (unlike most of his colleagues) in Paris by disciples of Pierre Fauchard (1678–1761), the father of modern dentistry. Gardette had constructed a set of uppers and lowers and left them with a patient, planning to attach the required springs some weeks later. When he returned, Gardette discovered to his amazement that the woman had been wearing her dentures without the springs. At that time most full uppers were carved similarly to lowers: horseshoe-like (with no piece lying against the roof of the mouth), to facilitate production, make them lighter, and provide more room for the tongue. But the palate of Gardette’s uppers extended far enough back to create a seal, and the teeth thereby stayed in place by suction—what Gardette called “atmospheric pressure”—when they came into contact with the roof of the woman’s mouth.

This new method of holding dentures in place was promising, but in the early nineteenth century dentists did not have the proper material to apply it consistently and cheaply. Partial upper dentures could be made with gold or silver palates that adhered fairly well, but these were expensive and often still required retention springs. Ivory and, for greater density, hippopotamus tooth remained the favored base materials for full dentures, but these were usually too heavy and ill-fitting to create the necessary seal. So until the 1850s most dentists continued using the awkward retention springs to stabilize full upper dentures. The material that would eventually revolutionize dental prosthesis and enable dentists to apply Gardette’s discovery effectively, consistently, and cheaply came out of the workshop of an indigent Yankee hardware merchant and inventor named Charles Goodyear.

Since 1834 Goodyear had been experimenting with a substance the South American Indians called caoutchouc , meaning “the tree that weeps.” (See “Crazy About Rubber,” Invention & Technology , Winter 1990.) For more than a half-century this substance had been commonly used for rubbing out lead-pencil marks from paper, so it was given the name rubber . It had found other uses (as a coating for cloth to produce rain gear, for example), but it was unstable, deteriorating under certain conditions of temperature and climate. In cold weather it stiffened and became brittle; in hot, it softened almost to melting.

Goodyear was convinced that if rubber could be stabilized, its uses would be unlimited. He staked his fortune and reputation on this idea, but years ” of trial and effort proved fruitless until, in 1839, he accidentally dropped a piece of rubber mixed with sulfur upon a hot stove. Goodyear assumed that the substance would melt, but to his surprise he found that the intense heat actually hardened it, rendering it firm but still pliable. Years of further experimentation and refinement resulted, in 1851, in a brownish-black substance that Goodyear dubbed Vulcanite after the Roman god who presided over fire and the working of metals.

Thomas W. Evans, an American dentist practicing in Paris, later said that he gave Goodyear the idea of using rubber to make bases for artificial teeth. Dentist to Louis Napoleon and one of the first to use anesthesia in Europe, Evans claimed to have been experimenting with caoutchouc since 1848. He heard of Goodyear’s success in stabilizing the material, and when Goodyear visited Paris in 1852, Evans called on him and discussed the use of rubber for dental purposes. “Here, again,” responded Goodyear exultantly, “is a new application which I never thought of!” (Goodyear also overlooked the use of rubber in manufacturing tires.) Evans believed that his own work was within the free domain of professional science and that an invention of such “great advantage to the profession and of immense benefit to humanity” should have unrestricted use. Several years later he was surprised and angry when a New York dentist showed him a set of artificial dentures made of rubber and stamped “Goodyear’s Patent.”

By 1858 Charles Goodyear’s brother Nelson had applied for and received amended patents covering both an improved form of vulcanization—the process of manufacturing hard rubber—and the resulting product, which, of course, had hundreds of potential applications. Though the 1858 patent did not mention it specifically, one of the most immediate and successful of those applications was in dentistry. Within a few years Vulcanite had effectively replaced the gold, silver, ivory, and animal bone that had been used in dental appliances since the Middle Ages.

Despite widespread acclaim, not all dentists were ready to accept Vulcanite. One New Jersey practitioner, Dr. J. B. Da Camera, Jr., complained in 1869 that it had “lowered the standard of mechanical dentistry,” since false teeth could now be produced cheaply and easily by anyone with a few weeks’ training. But even Dr. Da Camera had to admit that many of his patients could not afford “one hundred and fifty or seventy-five dollars for a set of teeth” made with gold or silver bases. By comparison, a set of upper and lower Vulcanite dentures could be purchased for about thirty dollars from a dentist, or for eight to ten dollars from individuals outside the dental profession (whom Dr. Da Camera called “unscrupulous, unqualified vampires”). Even at the dentists’ higher prices, however, it was clear that for the first time in history false teeth were no longer a luxury only the rich could afford.

More important, perhaps, than the egalitarian implications of Goodyear’s invention was the significance it had for dental health. Since it started as a soft rubber-sulfur compound, Vulcanite adapted precisely to plaster models of each patient’s gums and palate. After porcelain teeth were set in place, the three components—model, uncured Vulcanite, and teeth—were embedded in plaster and cured under pressure and heat for an hour or two in a vulcanizing apparatus. The finished denture was hard and durable, but it was also light—it weighed about half as much as a gold or ivory denture—and most important, it fitted the individual characteristics of the patient’s mouth. Thus Vulcanite uppers would stay in place, held fast with a seal strong enough to allow the wearer to smile, to speak, or even to eat (if the teeth were articulated properly) without fear of slippage. And this was all accomplished without springs. Acknowledging that Vulcanite had its faults, one dentist nevertheless responded to Dr. Da Camera’s criticisms by writing: “When we consider the thousands, aye, millions of plates that have been manufactured from it and worn with pleasure and profit, and that, too, by persons who could afford no other, we would scarcely be adhering to the truth did we not after all, acknowledge that vulcanized rubber has been a blessing to the civilized world at large, if not to the dental profession in particular.”

By the late 1850s, everyone associated with Vulcanite—the Goodyear company, thousands of dentists, millions of patients—appeared to be heading for brighter days. But it soon became apparent that potential profits resulting from the manufacture of rubber dentures could be far greater than anyone had dreamed, and a potentially cordial relationship between the Goodyear company and American dentists turned sour, led to rancor and prolonged legal battles, and finally culminated in violence.

At first the Goodyear company was content merely to sell its Vulcanite compound to dentists. But that was not where the real money was to be made. In 1868 Vulcanite cost $4 per pound, and from each pound a dentist could produce eight to ten single dentures, for which he might charge as much as $15 apiece. Thus a $4 outlay could generate as much as $150. Seen another way, a $15 denture contained less than 50 cents’ worth of Vulcanite. After overhead costs for vulcanizing equipment, labor, and porcelain teeth were figured in, a dentist made $6 to $8 on each full denture.

The possibility for this kind of profit encouraged many dentists to forgo more complex dental procedures. One dentist argued that rubber dentures were making mere mechanics out of professional men since “it was easier and would pay the practitioner better to insert artificial teeth than to attempt the preservation of the natural [ones].” Another gravely noted that “thousands upon thousands of teeth which might have been preserved have been sacrificed, owing to the limited expense of such dentures in comparison with the cost of saving the natural organs.” For their part, many economy-minded patients were only too willing to have even their sound teeth extracted, cheerfully exchanging them for those that “won’t ache.” (The spread of nitrous oxide as an anesthetic, first used by Horace Wells of Hartford, Connecticut, in 1844, also contributed to this trend.)

To increase its share of the gains, in the 1850s Goodyear began to charge licensing fees based on its patents and demanded a royalty on each denture produced. But during this period the company launched only halfhearted collection efforts, and most dentists ignored Goodyear’s claims. Then Josiah Bacon came upon the scene.

Bacon was neither a dentist nor an inventor but rather a wily Boston businessman who knew how to take advantage of an opportunity. By 1866, despite its lucrative products, the Goodyear company was nearly bankrupt as a result of heavy legal fees incurred in defending its patents, as well as poor business judgment. It was forced to sell some of its assets, and Bacon, who had been treasurer of the Goodyear Dental Vulcanite Company for several years, gained control of that company and its patents. Bacon also bought out the rights to a rival 1864 patent granted to Dr. John A. Cummings that specifically covered dental uses of Vulcanite. Thus he had a strong claim to patent rights on rubber dentures, and as treasurer of the company he proceeded to enforce its claims zealously.

Bacon instituted a licensing system for dentists, requiring annual fees of $35 to $50, depending upon the size of the practice, as well as a fixed amount for each denture produced. The licensing fees alone would bring in an estimated $700,000 a year, while the royalties for each denture ($1.00 to $2.50, depending on the number of teeth replaced) could easily match that figure. Although the royalty fee represented only about 10 percent of what a dentist might charge his patient, it sharply reduced profits per denture.

Moreover, everyone in the dental profession was convinced that licensing and royalty fees would increase dramatically after the first year, and according to the editors of Dental Cosmos , the most influential dental journal of the time, once the company had dentists under contract, it would “catch and hold them beyond redress for future and more oppressive demands.”

When dentists across the nation expressed outrage and refused to pay, Bacon launched a ruthless campaign in the courts. A notice in the Jacksonville, Illinois, Journal warned: “All dentists infringing on our patent and all persons employing them… will be prosecuted to the full extent of the law.” To carry out this threat, Bacon enlisted agents and spies to gather evidence. The New York Times article reporting his murder in 1879 said that “one of his favorite methods of discovering infringements … was to employ a beautiful young lady, whom no dentist would suspect.… She was liberal with her money, and only particular on the one subject of the rubber. This once obtained, she had all the evidence requisite to enable Bacon to bring suit.” The same article says that “servants of dentists were bribed; next door neighbors were questioned, and intimidation was often resorted to.”

In another scheme, Bacon set up a company that sold Vulcanite material at $2 per pound, half the price his Dental Vulcanite Company was charging, in order to find dentists who were trying to avoid dealing with him. When the scheme was uncovered, Dental Cosmos warned its readers: “After the company has received an order from a dentist for even a single pound of [Vulcanite] gum, it is strong presumptive evidence, to say the least, that he is vulcanizing rubber, and some fine day the company’s agent will call at his office with all necessary information and ask for a settlement.”

Among other objections to Bacon’s demands, dentists found repugnant his requirement of listing names and addresses of patients who had been sold Vulcanite dentures. “Every lady or gentleman who may be so unfortunate as to require a set of teeth,” wrote one dentist in 1866, “does not desire to have the fact published to the world; and yet the Company requires that each operation made shall be entered in a book (furnished for the purpose), along with the name of the party and the place of residence, this book to be accessible to the agent of the Company at such times as he may desire to look over it. The violation of confidence and privacy such a course implies, would be most inexcusable and reprehensible.”

Bacon’s campaign lasted thirteen years. During that time his legal machinations carried him across the country and galvanized the dental profession, one of whose members called him “the active and engineering Mephistopheles of this whole skinning raid upon the dentists.” In 1866 a group of New York dentists organized the American Dental Protective Society and issued a ringing declaration:

“Brethren of the dental profession throughout the United States! the cause that we have undertaken is that of a great profession against a great monopoly. We appeal to you, to yield your vigorous and untiring support to our efforts; and, in return, this Society pledges itself to you, to leave nothing undone toward the overthrow of these illegal claims, and to secure to the dental profession for all time, the free use of all vulcanizable compounds.”

At the same time, the Northern Ohio Dental Association at a special meeting on October 11, 1866, exhorted its members to ignore Bacon’s claims and offered to render “any and all dental societies and associations our cordial co-operation in any endeavor they may undertake to defend themselves.” Members of the Central Ohio Dental Association contributed one hundred dollars apiece—double the amount of a Vulcanite license—to assist in the defense of dentists facing prosecution.

For their efforts, dentists did win a few cases in lower courts, sometimes by showing that they had used a different type of rubber. But these setbacks did not stop Bacon from going on the attack elsewhere. As one despondent dentist reported, their group was “no match for a thoroughly organized Company composed of experienced, shrewd, and sharp businessmen.”

Although he seemed to relish hauling dentists into court and even cross-examining them himself, Bacon wanted to end his legal scrimmage with a judgment from the U.S. Supreme Court. Not surprisingly, the awakened brotherhood of dentists was also aiming to defend its cause before the justices. The dentists’ legal adviser was the distinguished patent attorney (and defender of Dred Scott) George Ticknor Curtis, who assured them that their case was strong, because the Cummings patent of 1864 had been granted on questionable grounds after being turned down twice. He added, “Not only your own profession, but the kindred professions of medicine and surgery [would render] their moral support.”

But even with the formidable Curtis as their lawyer, the dentists were outmaneuvered by Bacon. After securing a lower-court ruling in 1868 against Dr. Benoni E. Gardner, an aging, obscure Rhode Island practitioner, Bacon secretly engineered an appeal by Gardner to the U.S. Supreme Court. This appeal was pursued only weakly, and Bacon correctly anticipated that it would be dismissed, as it was on May 6. 1872.

The Supreme Court’s decision not to hear Dr. Gardner’s appeal appeared to establish for all time Bacon’s legal right to exact royalties on Vulcanite dentures. But his victory was short-lived. The doughty Dr. Samuel S. White, a manufacturer of dental supplies, publisher of Dental Cosmos , and one of the dentists’ chief organizers, sensed that the profession had been set up. He conducted his own investigation into the Gardner appeal, and on October 29, 1872, he submitted affidavits and statements to the Supreme Court proving that, among other things, counsel for both sides had been on Bacon’s payroll, resulting in what White called “a deliberate contempt upon this highest tribunal of our country.” Faced with the evidence of collusion, the Supreme Court reversed itself for the first time in its history.

To the dentists the reversal was bittersweet. It meant that they could continue to contest the validity of Bacon’s patents, that they still had a fighting chance, but it also meant that Bacon, even though he and his company had been publicly discredited, could continue to sue and harass them. At last the dentists did get their own long-awaited test case. On January 8, 1877, however, the Supreme Court determined that Bacon’s claims were valid—that he had a legal right, not only to the process of vulcanization as it applied to the manufacturing of dentures, but even to the actual dentures themselves made by that process. Dr. White called this “The Final Decision,” but many dentists still refused to take out licenses or pay royalties. Bacon doggedly pursued these holdouts in a redoubled campaign lasting another two years, a campaign that ended only when he lay murdered on a hotel-room floor.

On Easter Sunday morning in April 1879, Dr. Samuel P. Chalfant, a prominent San Francisco dentist, visited the hotel room of Josiah Bacon, the man who had hunted him for nearly a decade. For years Chalfant had refused to pay Bacon’s fees, and to avoid prosecution he had abandoned lucrative practices in Delaware and Missouri. He had finally established himself in San Francisco, and there, when Bacon once again tracked him down, he determined to make a stand.

Just the day before, Chalfant had been in court answering Bacon’s charges of patent infringement. Following a humiliating cross-examination, Chalfant decided to propose a settlement, and it was ostensibly for that purpose that he visited Bacon early the next morning. According to Chalfant’s subsequent statements, Bacon was unmoved and proposed to make an example of him. The beleaguered dentist then drew a pistol, “intending only to compel Bacon to deal with him more respectfully,” as one account of the incident puts it, but Bacon instead became infuriated. During the dispute the pistol fired, and the man a later historian called “the Nemesis of the dental profession in the United States” was killed by a single bullet in the abdomen.

Chalfant later claimed that he went from the hotel directly to the local police station, but since it was Sunday, no one was there. He then hid for three days in a rooming house before surrendering to the police.

At his trial Chalfant was portrayed as a victim, a respected citizen driven to desperation by a rapacious scoundrel, and dentists from all over the United States contributed funds for his defense. Convicted of second-degree murder, Chalfant was sentenced to ten years at San Quentin. Following his release he again took up the practice of dentistry in San Francisco, this time without the fear of prosecution for using Vulcanite.

The aggressive legal campaign against dentists ended with Bacon’s death, and when the Vulcanite patents expired, on June 7, 1881, his company did not renew them. Dentists were finally free to make available to their patients the most important advance in dental prosthetics in centuries.

By the 1930’s dentists were experimenting with other materials as denture bases, and eventually Vulcanite would be entirely supplanted by the acrylic resins now in use. Yet repercussions from the episode continue to this day. In the closing statement of a 1984 article in the Bulletin of the History of Dentistry in which he uncovered much of the history surrounding the Vulcanite litigation, Dr. Malvin E. Ring admonished his colleagues, “Even today there are attempts to license techniques and processes which are legitimate parts of a health service, and only vigilance on the part of organized dentistry can keep these plans from fruition.”

More than a century after his death, the lesson of Josiah Bacon has not been lost on the dental profession. And as debate over the uses and misuses of patents continues, all fields of technology have something to learn from his story.