The primary objectives of the study were to investigate the levels of volatile sulfur compounds
(VSCs) in Iranian patients and to find the most prevalent class of halitosis among them. The
secondary objective was to study the measures employed by the patients to reduce halitosis.
46.4% of the 222 patients were female (average 32.1 years) and 53.6% were male (average
32.1 years). Contrary to other reports, males were dominant in this study. All the subjects
were evaluated through oral examination, gas chromatographic analysis, organoleptic
assessment and mouth cleaning and rinsing test (MCART). Finally, each patient was classified
according to current classification. The patients were also asked about the measures employed
by them to reduce halitosis. The data were statistically analysed using SPSS software. Gas
chromatographic analysis revealed that the median values for H2S, CH3SH and (CH3)2S levels
were 214 ppb, 64 ppb and 2 ppb, respectively. Average values of H2S, CH3SH and (CH3)2S
were 358.7 ppb, 143.0 ppb and 19.5 ppb, respectively. A correlation was demonstrated
between organoleptic scores and the concentration of only H2S, CH3SH and the total of three
gases. In 62.2% of the subjects, no oral pathologic condition was found, but tongue coating
was observed. The patients were in only class I (genuine halitosis) and class II
(pseudo-halitosis) halitosis. None of them was diagnosed as halitophobia. The percentages of
classes I and II were 98.6% and 1.4%, respectively. The percentages of sub-classes of class I
halitosis in total subjects were as follows: 60.8% physiologic halitosis, 37.8% oral pathologic
halitosis and 0% extraoral pathologic halitosis. The mean value of organoleptic score for
physiologic halitosis was 4.0 and those for oral pathologic halitosis and pseudo-halitosis were
4.3 and 1.6, respectively. MCART was a useful tool to distinguish oral halitosis from extraoral
halitosis. Levels of VSCs were not as high as those measured in other countries. Although in
most cases VSCs were a contributing factor to halitosis, VSCs levels were not useful
diagnostic criteria for the minority of the patients. The most prevalent class and sub-class of
halitosis in the patients were genuine halitosis and physiologic halitosis. Measures employed
by the patients to reduce halitosis were mostly related to the oral cavity