Discrimination of oral malodor components in elderly patients by e-nose

Objectives: The aim of this study is to compare the oral malodor components (saliva, denture, tongue coat) and the breath in elderly patients to see which component has similarity to the breath odor. Methods: Patients whom arrived at the Tokyo Medical and Dental University Geriatric Dentistry out patient clinic were asked for volunteers. Their saliva, denture, tongue coat and breath were taken from the patients, than their vapors were collected in a sampling bag. The sampling gases were measured by an electronic nose(Odor Discrimination Analyzer FF-1, Shimazdu, Japan), and the sensor responses were analysed by principle component analysis (PCA). Organoleptic judgement was performed to see the relationships between the oral malodor and the e-nose responses. Results: The PCA results showed clear differences between breath and the saliva, breath and the denture, breath and the tongue coat. There were no clear differences among the saliva, denture and the tongue coat. There were no clear differences among the odorous patients and patients without odors. Conclusion: In this study, tongue coat which is assumed as one of the main cause of breath odor has no similar trend with the breath odor. Moreover, tongue coat has similar trends to saliva and the dentures in the elderly patients by the PCA results.