A salivary incubation test for evaluation of oral malodor: a pilot study.

Breath odor is scored by different techniques, each with its own shortcomings. Organoleptic ratings are uncomfortable for the patient, subjective, influenced by external parameters including food and cosmetics, and especially lack international calibration. Portable sulphide monitors are relatively expensive and neglect several major malodorous molecules (e.g., butyric and propionic acids, putrescine, and cadaverine). Gas chromatography necessitates expensive devices and experienced technicians. This pilot study explored the applicability of a new technique (saliva incubation) by comparing its discrimination power, in a morning bad breath inhibition study of antiseptics, to those of hydrogen sulphide (H2S) measurement devices and organoleptic ratings. After a professional cleaning, 8 periodontally healthy students abstained from all means of mechanical plaque control for 5 experimental periods of 7 days, with intervening washout periods of at least 2 weeks. During each experimental period, the students rinsed only twice daily with different antiseptics. At day 7, morning breath was scored clinically (volatile sulphide compound [VSC] level and organoleptic ratings), and 1.5 ml of saliva was collected and divided between 3 glass tubes that were sealed and incubated (37 degrees C, anaerobic chamber). Immediately after collection and after 3 and 6 hours of incubation, the headspace air in one of the tubes was examined for VSC production and organoleptic measurements. The investigations of the incubated saliva correlated well with the 7-day intraoral VSC recordings and organoleptic ratings (P < or = 0.005). Moreover, evaluations showed a similar interproduct ranking for their efficacy in malodor control. The power analyses indicated a higher discrimination power for the saliva incubation test than for the intraoral registrations. The strong correlation between odor production of incubated saliva and clinical assessments suggests that the saliva incubation test may be used as an indirect method to measure oral malodor and can be employed to investigate the antimalodor effectiveness of oral hygiene products.