Journal of Dental Research, Vol 76, 1770-1775, Copyright © 1997 by International & American Associations for Dental Research Online Journals
Isolation of Enterobacteriaceae from the mouth and potential association with malodor
S. Goldberg, H. Cardash, H. Browning 3rd, H. Sahly and M. Rosenberg
Maurice and Gabriela Goldschleger School of Dental Medicine, Ramat-Aviv, Tel Aviv, Israel.
Bad breath is a common phenomenon, usually the result of bacterial
metabolism in the oral cavity. It is generally accepted that Gram-negative
bacteria are responsible for this problem, largely through degradation of
proteinaceous substances. In initial experiments, screening of malodorous
isolates following outgrowth of samples obtained from saliva, periodontal
pockets, and the tongue dorsum yielded enterobacterial isolates. Clinical
studies were conducted to examine the prevalence of such bacteria in four
different populations: orthodontic patients, malodor clinic patients,
complete-denture wearers, and a healthy young population. The prevalence of
Enterobacteriaceae in the oral cavities of the denture-wearing population
was very high (48.0%) as compared with the other groups: 27.1% in the
malodor clinic patients, 16.4% in the normal population, and 13% among
orthodontic patients. Isolates of Klebsiella and Enterobacter emitted foul
odors in vitro which resembled bad breath, with concomitant production of
volatile sulfides and cadaverine, both compounds related to bad breath.
When incubated on a sterile denture, enterobacterial isolates produced
typical denture foul odor. Isolates exhibited cell-surface hydrophobic
properties when tested for adhesion to acryl and aggregation with ammonium
sulphate. The results, taken together, suggest that Klebsiella and related
Enterobacteriaceae may play a role in denture malodor.
