The introduction of anaesthetics had a dramatic effect on dentistry. The first successful public demonstration of anaesthetic was in 1846 in Boston when the American dentist William Morton administered ether to remove a tumour from a jaw. Later that year, the first ether anaesthetic in England was administered by English dentist James Robinson, who used ether for removal of a diseased molar from a patient in London.
Ether is a colourless, volatile liquid with a characteristic smell. It is not an ideal anaesthetic, though it is safer than chloroform and more effective than nitrous oxide. James Simpson, Professor of Obstetrics in Edinburgh, introduced chloroform in 1847. It was more potent and could have severe side effects, however it became popular because it worked well and was easier to use than ether.
In 1877, Joseph Clover produced the portable regulating ether inhaler. It was the first apparatus to regulate the amount of ether inhaled. As a result it quickly became popular. It consisted of a face piece which would have been edged with a padded cushion. The spherical chamber was prepared with an ounce and a half of ether which was poured into the ether chamber. There was warm water in the water compartment. When the stopper is at the top the patient breathes directly into the bag. When the stopper at the top is rotated to the base of the cylinder the internal valves direct the air over the ether and the patient breathes in ether vapour. The scale indicated the proportion of air to ether vapour. Clover’s apparatus remained the basic method for many years although the design was modified.
Chloroform and ether only knocked the patient out for a limited period of time so only short operations such as extractions were possible. This required the dentist to work quickly and efficiently. Both vapours caused serious side effects and sometimes resulted in death. It soon became clear that neither ether nor chloroform was ideal. Dentists returned to using nitrous oxide which had been discovered much earlier and had gain notoriety at laughing gas parties. It was not until nitrous oxide was mixed with oxygen that longer operations became possible.
Most surgeries were equipped with general anaesthetic equipment by the twentieth century. The invention of the hypodermic syringe in the 1850s made anaesthesia possible by injection. Cocaine and ethyl chloride were used to numb specific areas of the mouth and enabled a local anaesthetic to be administered. Many people were now prepared to have fillings and more lengthy dental treatment.