Dentistry

There was a book sale at Sydney University this weekend and I picked up a copy of Text-Book and Atlas of Dentistry, Gustav Preiswerk, edited by George W. Warren (1906). It is well illustrated but I detected a hint of anxiety in the patient's faces. When I read the section on anesthesia I realised why this might be. Here is the introduction:

Dental operations, especially extraction of teeth, are frequently very painful, and, therefore, we are compelled, in nervous and sensitive patients, to resort to pain-alleviating or pain-destroying remedies.
The action of such anesthetics is limited, either to the part being operated upon (local anesthesia), or to the whole body (narcosis).
Local anesthesia may be produced by thermic action (cold), mechanical action (swelling of the nerve fibres and pressure upon the same) and by chemical action.
Anesthesia by means of cold is best obtained with evaporating substances, such as ethyl chlorid (chlorethyl), which finds its greatest field of usefulness in dentistry. Before applying ethyl chlorid, the neighbourhood of the tooth to be extracted should be protected, so that it will not be affected by this liquid. This is done by covering the neighbouring teeth with a layer of softened wax, cotton rolls, or a napkin. The commercial ethylchlorid, which is obtained in tubes, is then directed both upon the labial and lingual side of the alveolus of the tooth to be extracted. Since ethyl chlorid boils at 11° C., the tube may be held quite some distance from the field of operation, for the heat of the hand is sufficient to cause the expansion of this preparation, and to force a strong stream to be be sprayed forth. After the spray has been allowed to act upon the gum for from ten to fifteen seconds, a shiny white coating of frost is formed, which indicates that that the operation may be begun. The latter is thus made decidedly more bearable, and especially so, if in association with the the local action of the cold, a light general anesthesia is produced by inhalation of gas. Ethyl chlorid is also recommended for minor operations upon the mouth, such as removals of growths, etc. It is sometimes also of good service in the extraction of living pulp. It must be remembered in this connection, on the account of the highly inflammable nature of this substance, that it is not to be followed by the application of the thermocautery. The consequences of such a mistake are illustrated by the following case: "When this method was still new, the writer wished to burn away an epulis frozen in the above manner. As the oral cavity was approached with the red-hot cautery, a flame blazed forth from it. Luckily no burn-wounds developed, and, aside from the shock, there will be no ill effects."

Further, the section on general anesthesia concludes:

In conclusion, we wish to particularly advise that anesthetization be never instituted without professional assistance, for, aside from the fact that frequent erotic dreams, in which the unconscious patient imagines she was ruined, have led to penal law suits, an assistant is also required for the institution of artificial respiration.
By fulfilling all of these requirements, one may have a clean conscience if an accident happens, and also the eventual resulting legal decision will not be unfavourable.