A NEW MONITOR WITH A ZINC-OXIDE THIN-FILM SEMICONDUCTOR SENSOR FOR THE MEASUREMENT OF VOLATILE SULFUR-COMPOUNDS IN MOUTH AIR

HALITOSIS, DEFINED AS UNPLEASANT ORAL ODOR, is a concern among the gen eral public. Halitosis is generally diagnosed by organoleptic examinat ion and by gas chromatographic analysis of the main source of halitosi s, volatile sulfur compounds, such as hydrogen sulfide, methyl mercapt an, and dimethyl sulfide. Gas chromatography requires a large-scale sy stem and a long running time. We investigated the use of a zinc-oxide thin film semiconductor sensor for measuring trace volatile sulfur com pounds in mouth air. Mouth air samples collected in teflon bags from 2 1 volunteers were analyzed by 3 methods: the monitor analysis, gas chr omatography, and organoleptic examination by 3 judges. The readings of the monitor were correlated with the values of the total volatile sul fur compounds measured by gas chromatography (r 0.75, P < 0.01) and al so with the organoleptic scores given by the judges (r = 0.76, P < 0.0 1). The organoleptic scores were correlated with the gas chromatograph ic values (r = 0.71, P < 0.01). These results suggest that this new mo nitor with a zinc-oxide thin film semiconductor sensor may be used for the diagnosis of halitosis. Its small size and simplicity of handling may enable its use for routine chair-side study and field surveys of halitosis.