Accessible halitosis diagnosis: validating the accuracy of novel AI-based compact VSC measuring instrument

Abstract Halitosis presents a significant global health concern, necessitating the development of precise and efficient testing methodologies owing to the high prevalence and the associated social and psychological effects. The measurement of volatile sulfur compounds (VSCs), recognized as primary contributors to halitosis, is particularly significant. While gas chromatography (GC-MS) offers accurate measurements, its bulky and expensive nature limits widespread accessibility. Hence, this study endeavors to devise a compact yet highly accurate AI-based halitosis measurement apparatus, termed ‘Kunkun dental’ and validate its efficacy. Specifically, we intend to compare the VSC concentrations obtained from halitosis patients’ breath samples using Kunkun dental against those from conventional GC-MS to assess the criterion validity of the new testing method. The study cohort comprised 68 halitosis patients aged 20 years or older, attending the breath freshening outpatient clinic at Tokyo Medical and Dental University Hospital between October 2022 and March 2023, who consented to participate and underwent routine measurements. Participants completed an age and sex questionnaire, while VSC concentrations were determined using both GC-MS and Kunkun dental (H 2 S, CH 3 SH, (CH 3 ) 2 S), enabling a comparative analysis of the results. Pearson product-moment correlation coefficients between GC-MS and Kunkun dental indicated significant correlations for all three gases: 0.719 for H 2 S, 0.821 for CH 3 SH, and 0.637 for (CH 3 ) 2 S. Moreover, sensitivity and specificity in accordance with the predefined thresholds were confirmed, and their values ranged from 0.59 to 0.86 and 0.53–0.77, respectively. Furthermore, grouping Kunkun dental measurements into low-, medium-, and high-concentration groups revealed significantly higher GC-MS VSC concentrations in samples with elevated Kunkun dental readings. The amalgamation of AI technology and a semiconductor gas sensor holds great promise in creating a compact and precise halitosis analyzer. This study underscores the feasibility and effectiveness of Kunkun dental as a reliable tool for halitosis assessment, affirming its utility in clinical practice.