Effects of metal salts on the oral production of volatile sulfur-containing compounds (VSC).
OBJECTIVE
Halitosis, mainly caused by bacteria located on the posterior dorsum of the tongue and in periodontal pockets, is due to formation of volatile sulfur compounds (VSC). The hypothesis to be tested was that the affinity of a metal for sulfur determines its anti-VSC activity.


METHODS
Clinical tests were carried out on 12 subjects who rinsed with cysteine to induce halitosis (baseline) before rinsing with 7.34 mM ZnCl2, SnF2 and CuCl2. Mouth air VSC analyses were repeated following cysteine rinses at 1 h, 2 h and 3 h using a gas chromatograph. In vitro experiments tested toxic metals Hg2+, Pb2+ and Cd2+. 10-microl aliquots of metal salts were added to 1-ml aliquots of human whole saliva from 30 subjects. Samples were incubated overnight at 37oC and saliva headspace was analyzed for VSC in a gas chromatograph.


RESULTS
Cu2+>Sn2+>Zn2+ (supports hypothesis). Zn2+ had significantly less anti-VSC effect compared with Cu2+ and Sn2+ at 1, 2 and 3 h. In vitro results indicated that Hg2+, Cu2+ and Cd2+ had close to 100% anti-VSC effect, and that Pb2+ was less effective and Cd2+ more effective than expected in inhibiting VSC.


CONCLUSIONS
Apart from Hg2+ and Cu2+, the metals had a significantly greater effect on H2S than on CH3SH. Cu2+ and Hg2+ have well-known antibacterial activity and may presumably also operate by this mechanism.
Young
A
A
Department of Cariology, Faculty of Dentistry, University of Oslo, PO Box 1109 Blindern, N-0317 Oslo, Norway. alixr@odont.uio.no
Jonski
G
G
Rölla
G
G
Wåler
S M
SM
D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D001944:Breath Tests; D019256:Cadmium Chloride / Q000627:therapeutic use; D002712:Chlorides / Q000627:therapeutic use; D003300:Copper / Q000627:therapeutic use; D003545:Cysteine / Q000008:administration & dosage; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D006209:Halitosis / Q000139:chemically induced / Q000517:prevention & control*; D006801:Humans; D006862:Hydrogen Sulfide / Q000032:analysis*; D066298:In Vitro Techniques; D007854:Lead / Q000627:therapeutic use; D008297:Male; D008627:Mercuric Chloride / Q000627:therapeutic use; D008670:Metals / Q000008:administration & dosage* / Q000737:chemistry; D008875:Middle Aged; D009067:Mouthwashes / Q000008:administration & dosage*; D012463:Saliva / Q000737:chemistry* / Q000187:drug effects; D013438:Sulfhydryl Compounds / Q000032:analysis*; D017971:Tin Compounds / Q000627:therapeutic use; D016896:Treatment Outcome; D014835:Volatilization; D017967:Zinc Compounds / Q000627:therapeutic use
D002712:Chlorides; D008670:Metals; D009067:Mouthwashes; D013438:Sulfhydryl Compounds; D017971:Tin Compounds; D017967:Zinc Compounds; C023599:stannous chloride; D007854:Lead; C029891:lead chloride; D008627:Mercuric Chloride; D003300:Copper; C016837:zinc chloride; D019256:Cadmium Chloride; D003545:Cysteine; C029892:cupric chloride; D006862:Hydrogen Sulfide