Dan Y. Burrill

Chemical Studies in Periodontal Disease

It has been shown that saliva from individuals suffering from periodontal disturbances will putrefy more rapidly than the saliva from individuals with normal periodontal tissues (1). The small differences noted were obtained by methods that determined only the increase in carboxyl groups and the increase in malodorous substances, and hence may not be a true measure of the actual rate of putrefaction. In the process of putrefaction, the protein molecule is probably first hydrolyzed to amino acids, after which the amino acids undergo decarboxylation, a deaminization and certain oxidation-reduction reactions (2). When a protein is hydrolyzed, each peptide linkage yields an amino group and a carboxyl group. Thus, if no further actions were involved, the formol titration, which determines the number of free carboxyl groups, would be an accurate indication of the amount of hydrolysis that had occurred. However, decarboxylation, deamination and oxidation-reduction reactions also occur. Furthermore, it has not been definitely established whether these reactions occur according to a definite sequence, or whether they may occur simultaneously. If the rate of hydrolysis were faster than the decarboxylation, there would be an accumulation of carboxyl groups and the formol titration would yield quite accurate results. If decarboxylation were faster than the hydrolysis, little change in the number of carboxyl groups would occur and the hydrolysis could not be estimated by this method. Of the amino acids progressively formed by hydrolysis during putrefaction, only a few, such as tyrosine and tryptophane, can be rapidly and accurately estimated in saliva by available methods. However, certain degradation products, such as indole from tryptophane, phenol from tyrosine, and sulfides from the sulphur-bearing amino acids, can be estimated, thus frunishing a rough measure of the amount of decarboxylation, deaminization and oxidation-reduction. Furthermore, many compounds formed by these latter reactions, such as cadaverine, skatole and sulfides, are malodorous, and hence may be detected in small quantities by means of the osmoscope. Mucin is rich in amino acids which yield these compounds (3). In the present continuation of the earlier work, the rate of putrefaction of the salivary proteins was measured by means of the formol titration and by estima-

Chemical Studies in Periodontal Disease. IV. Putrefaction Rate as Index of Periodontal Disease

When the putrefaction rate of saliva is determined, values are obtained which seem to be related to the periodontal condition of the mouth of the patient from whom the saliva was taken. It has appeared that such saliva analysis might constitute a test for susceptibility to periodontal disturbances and that the test might be useful clinically as the now common salivary tests for caries susceptibility are useful. Accordingly, the present experiment was set up to determine how well the results of the salivary analyses correspond with clinical and radiographic findings in a fairly large group of patients.

Relationship of Blood Plasma Vitamin C Level to Gingival and Periodontal Disease

In the years since vitamins were first discovered much has been learned of many of the vitamins, but the relationships between them and oral health have remained obscure. It is a pleasant and worthwhile undertaking, therefore, to try to add even a little to the store of knowledge of those relationships. Vitamin C is one of several vitamins which may be necessary for maintenance of oral health. The oral effects of a deficiency of vitamin C may be confused with, and complicated by, a number of other factors. Improper mouth hygiene, deposits on the teeth, faulty tooth brushing, malocclusion, and other local causes may be partly or wholly responsible in any one case for the symptoms which may seem to be chargeable to lack of vitamin C. Deficiencies of several vitamins at once might produce changes in the mouth comparable to changes caused by more severe deficiencies of vitamin C alone. For these reasons, the study of the relationship between vitamin C and the condition of the gingival and periodontal tissues should depend on data from a large number of cases. If the number is large enough it may be possible to discount many variables and learn the effects of low levels of vitamin C alone. In the present paper records of 1396 patients are considered in an attempt to determine what correlation there may be between vitamin C levels in the blood plasma and the common afflictions, gingivitis and periodontal disease.

The Pain Threshold Raising Effects of Amphetamine

From Northwestern University Dental School and the Department of Physiology, Northwestern University Medical School, Chicago, Ill. It has been known for some time, though not generally recognized, that various sympathomimetic drugs manifest an analgesic effect. The literature on this subject has been reviewed by Ivy, Goetzl, Burrill, and Harris (1). From studies on mice and dogs (2, 3) it was learned that amphetamine possessed such analgesic and other effects that it might be useful clinically in the control of pain. As preliminary to other clinical investigations, the present experimental study on human subjects was undertaken for the purpose of comparing the pain threshold raising effects of the isomeres of amphetamine with like effects of other wellknown drugs.

The Effect of 2-Methyl-1,4-Naphthoquinone on the Incidence of Dental Caries

In 1943 it was suggested that the production of dental caries depends upon first, the rate of acid formation in the mouth, and second, the rate of neutralization of acid in the regions associated with the caries susceptible portions of the teeth (1). On this basis dental caries should be retarded by a decrease in the rate of acid formation or an increase in the rate of acid neutralization. Most of the successful methods of controlling caries have worked by decreasing the rate of acid formation. This is natural, because the rate of acid neutralization is controlled by many factors which at present cannot be materially changed (1). Probably the most successful experimental control of the rate of acid formation, with subsequent decrease in caries activity, has been accomplished by the reduction of fermentable sugars and carbohydrates in the diet (2, 3, 4), or by their elimination from the mouth through oral hygiene (5). These methods of caries control, however, depend entirely upon the cooperation of the patient. This cooperation cannot be expected of large masses of population. Another way of reducing the rate of acid formation is by interfering with the enzyme or co-enzyme systems which are necessary for acid production. Several agents may be used, some of which have been tried experimentally and some clinically. Iodoacetic acid has been tried experimentally with rats (6). It is probably too toxic for human use. A 30% urea solution (7), used as a mouthwash, acts as a protein denaturant, destroying the enzymes and hence preventing acid formation. A urea quinine mouth rinse has also proved successful (8). Ammoniacal silver nitrate reduced on the susceptible surfaces of the teeth leaves a deposit of colloidal metal which presumably retards fermentation (9). The enzyme inhibitor which has had the most wide-spread study and experimental use is the fluoride ion (10). This ion inhibits the hydrolysis of phosphoric esters and hence retards acid formation. Furthermore, the fluoride ion is absorbed by the dental enamel, forming a compound less soluble than unchanged enamel. Probably both actions are responsible for the success of fluorides in controlling or preventing caries. In 1942 (11, 12), it was found that synthetic vitaminK (2-methyl-1 ,4-naphthoquinone), when added in minute quantities to saliva-glucose mixtures, in vitro, would prevent the formation of significant amounts of acid. There was no evidence that its action as an enzyme inhibitor was closely associated with the vitamin activity. Preliminary experiments indicated that the material would

The Analgesic Effect of Morphine Alone and in Combination with Dextro-Amphetamine.

Summary Experiments have been made on mice which demonstrate that dextroamphetamine increases the analgesic effects of morphine while counteracting its narcotic action. Although a different method has been used in these studies the results agree with those obtained in dog experiments.

Changes in caries susceptibility with age and sex.

Clinical observations have been reported indicating that tooth decay increases during adolescence and comparing the amount of decay suffered by males with that of females (1-7, 10-18). These reports are based on determinations of the numbers of decayed, filled or missing teeth. There must, however, be a lag between the time when the susceptibility to decay increases and the time when the increased decay becomes clinically apparent. In the present study, the results of tests indicating the susceptibility to caries at the moment of the test are presented in a comparison of the susceptibility of the sexes at various ages. Records of age, sex and caries susceptibility of 3478 patients from the Diagnosis Clinic of Northwestern University Dental School provided the material. Bacteriological determination of caries susceptibility had been made for each patient, and chemical determinations for some. There was no selection of patients as to age, sex, or condition, except that all came to the clinic for dental service. Most of the younger people appeared at the clinic because of tooth decay. The older people came in because of decay and also because of gingival and periodontal disturbances and for construction of prosthetic appliances.