Before restorative dental care was available, the only treatment for dental pain was extraction. Unfortunately there were no suitable materials or techniques available for the fabrication of satisfactory dentures. The problem was the lack of a durable and affordable denture base material (porcelain denture teeth were already developed). Swaged gold, and carved ivory were used but were expensive and only affordable to the rich.
In 1843, the American Charles Goodyear discovered how to make flexible rubber, named vulcanite, which he made from India rubber (caoutchouc). In 1851, his brother, Nelson, patented an improved manufacturing process to produce hard rubber. Vulcanite found instant use in the fabrication of denture bases world-wide and quickly replaced previously-used materials as it was cheaper. Ivory dentures cost 25 guineas (a year’s wages for a housemaid). By comparison, a set of vulcanite dentures cost six guineas. By luck, vulcanite dentures also became available just after the introduction of anaesthesia. People who had preferred toothache to the pain of extraction were prepared to have their rotten teeth removed, creating a demand for the new vulcanite dentures. For the first time in history false teeth were no longer a luxury only the rich could afford and were available to the middle classes.
Vulcanite starts out as a soft, rubber-sulphur compound. It fits precisely to a model of a patient’s gums and palate. Porcelain teeth were added, and the three components, model, uncured vulcanite and teeth, were embedded in plaster and cured in a vulcanizing apparatus. The finished hard rubber denture was hard, durable, light and had an excellent fit. Vulcanite uppers were self retaining, with suction cups, making springs obsolete. Patients could smile, speak and eat without fear of slippage. The main disadvantage was that the material was dark-red colour. To obtain the pink colour, to resemble gum, weakened the vulcanite. To give it sufficient strength, a facing of pink was incorporated into a denture made of stronger rubber. A better aesthetic solution was achieved by using teeth with an attached section of pink porcelain gum.
In 1864 in the USA, the Goodyear Dental Vulcanite Company was founded and every dentist had to obtain an expensive licence to use the material and was charged a royalty for each denture made. Although many dentists bought licenses, the dental profession as a whole opposed the patent and licensure and protested. The Goodyear Company prosecuted non-compliant dentists in the USA. The struggle reached a climax when Goodyear’s financial director, Josiah Bacon, was shot dead by Samual Chalfant, a dentist, in 1879.
The Goodyear patents ran for 25 years finally expiring in 1881 when dental vulcanite came into general use world-wide. In the UK in 1881, vulcanite dentures dropped in price to £5. Vulcanite dentures were the first functional, durable and affordable dentures, marking a great advance in dental treatment for the masses.
Source: British Dental Association