Important Variables for Halitosis Clinical Trials: Causes, Diagnostic Methods and Treatments

Abstract

In 80–90% of all cases, the oralmalodor is caused by production of volatile sulfur compounds (VSC), which are hydrogen sulfide (smells like rotten egg), methyl mercaptan (rotten cabbage) and dimethyl sulfide (rotten cabbage). This last one is present in non-dental causes (from lungs, liver, kidneys and must be better investigated by a clinical physician [5,6]. The VSCs derive from gram negative, anaerobic bacteria found in periodontal pockets and in the crypts at the back of the tongue [7,8]. The oral malodor upon waking is usual and can be related to several factors including reduced saliva production during the night [9], increased microbial metabolic activity during sleep [10], as well as mouth breathing [11].