Professor

<strong>Targeted Chemometrics Investigations of Source-, Age- and Gender-Dependencies of Oral Cavity Malodorous Volatile Sulphur Compounds</strong> Halitosis is a highly distressing, socially-unaesthetic condition, with a very high incidence amongst the adult population. It predominantly arises from excessive oral cavity volatile sulphur compound (VSC) concentrations, which have either oral or extra-oral etiologies (90-95 and 5-10% of cases, respectively). However, reports concerning age- and gender-related influences on the patterns and concentrations of these malodorous agents remain sparse; therefore, this study’s first objective was to explore the significance and impact of these potential predictor variables. Moreover, because non-oral etiologies for halitosis may represent avatars of serious extra-oral diseases, the second objective was to distinguish between etiology- (source-) dependent patterns of oral cavity VSCs. Oral cavity VSC determinations were performed on 116 healthy human participants using a non-stationary gas chromatographic facility, and following a 4 hr. period of abstention from all non-respiratory oral activities. Participants were grouped according to age band and gender. Statistical analyses of VSC level data acquired featured both univariate/correlation and multivariate (MV) approaches. Factorial analysis-of-variance and MV analyses revealed that the levels of all VSCs monitored were independent of both age and gender. Principal component analysis (PCA) and an agglomerative hierarchal clustering strategy demonstrated that VSC predictor variables were partitioned into two components, the first arising from orally-sourced H₂S and CH₃SH, the second from extra-orally-sourced (CH₃)₂S alone (58 and 35% of total PCA variance respectively). In conclusion, oral cavity VSC concentrations appear not to be significantly influenced by age band and gender. Furthermore, (CH₃)₂S may serve as a valuable biomarker for selected extra-oral conditions.