title: Effect of visible light on malodour production by mixed oral microflora.
abstract: Oral malodour is considered to be caused by the proteolytic activity of anaerobic Gram-negative oral bacteria. In a previous study, it was shown that these bacteria were susceptible to blue light (wavelengths of 400-500 nm). In this study, the effect of blue light on malodour production by mixed oral microflora was tested in a salivary incubation assay. Whole saliva samples were exposed to a xenon light source for 30, 60, 120 and 240 s, equivalent to fluences of 34, 68, 137 and 274 J cm(-2), respectively. Malodour was scored by two judges. The levels of volatile sulfide compounds (VSC) were measured using a sulfide monitor (Halimeter), the microbial population was assessed using viable counts and microscopy, salivary protein degradation was followed by SDS-PAGE densitometry and VSC-producing bacteria were demonstrated using a differential agar. The results showed that the exposure of mixed salivary microflora to blue light caused a reduction in malodour production concomitant with a selective inhibitory effect on the population of Gram-negative oral bacteria. These results suggest that light exposure might have clinical applications for the treatment of oral malodour.
authors.affiliation: The Hebrew University - Hadassah School of Dental Medicine, Department of Prosthodontics, PO Box 12272, Jerusalem 91120, Israel.
authors.forename: Nir
authors.initials: N
authors.lastname: Sterer
authors.affiliation: The Hebrew University - Hadassah School of Dental Medicine, Department of Prosthodontics, PO Box 12272, Jerusalem 91120, Israel.
authors.forename: Osnat
authors.initials: O
authors.lastname: Feuerstein
mesh_terms: D004591:Electrophoresis, Polyacrylamide Gel; D006094:Gram-Positive Bacteria / Q000302:isolation & purification* / Q000378:metabolism / Q000528:radiation effects; D006209:Halitosis / Q000382:microbiology*; D006801:Humans; D008027:Light; D009812:Odorants; D012463:Saliva / Q000382:microbiology*; D012471:Salivary Proteins and Peptides / Q000032:analysis; D013440:Sulfides / Q000032:analysis*
chemical_list: D012471:Salivary Proteins and Peptides; D013440:Sulfides