Date of Award

Spring 1947

Document Type



Life & Environmental Sciences


From the beginning of modern medical knowledge, medical specialists in the area of the mouth have noticed that the tissues of the mouth were highly resistant to infection. And, with the advent of more thorough bacterial knowledge, the idea of such a high degree of resistance to infection became even more surprising since the decaying teeth, food particles, and the constantly sloughing epithelial membranes furnish an excellent environment for bacterial growth. Thus many investigators began to believe that an antibacterial agent was present in the saliva.

Up to the year 1954, the results obtained in investigation in this field were indecisive and quite often conflicting. From that date on, however, much investigation has been carried out, and authorities such as Dold, Weigmann, Lachele, Hsing, Koehn, Noeske, and Thompson have shown that a definite salivary inhibitory effect exists against diphtherial growth. Other investigators such as Clough, Taylor, Bibby, Bine, Ball, Berry, and Kesteren have also shown that a definite inhibitive action is present in the saliva that is effective against lactobacilli and other related organisms. Thus the body has a defense against pathological damage to the teeth as it has been shown, that the acids produced by lactobacilli are not only harmful to the enamel of the teeth, but are also a predisposing cause of dental caries.

Authorities now believe that the inhibitory effect is due to powers other than those of the bacteria present in the saliva, but results of investigation in this field have been contradictory.