Association between Purpose in Life/(Ikigai), Prefrontal Cortex Function, and the Prevention of Halitosis Caused by Mental Stress, Pseudo-Halitosis, and Halitophobia

Halitosis is a condition characterized byunpleasant oral odor or oral malodor problems that can lead to social and psychologicalimpediments; it can be either genuine halitosis or pseudo-halitosis. One of theextra-oral conditions of genuine halitosis is mental stress, which causes areduction in both saliva secretion and the presence of salivary lysing agentsknown as lysozymes, leading to oral malodor. Even in the absence of objectiveoral malodor, persons with pseudo-halitosis complain of halitosis symptoms,while those with halitophobia have a fear of halitosis. Genuine halitosiscaused by stress, pseudo-halitosis, and halitophobia may all be due to anxietyresulting from an excessive need of approval from others. Purpose in life(PIL)/(ikigai), which is related to prefrontal cortex function, has been shown tobe an effective way to manage stressful events, and is negatively correlatedwith an excessive need of approval from others. PIL/(ikigai), similar to prefrontal cortex function, develops through positiveexperiences from infancy to adolescence, such as spending time in beautifulnatural surroundings, having success at meeting valued goals, and gainingempathetic acceptance and affection from others. Understanding the traits anddevelopmental conditions associated with PIL/(ikigai) and prefrontal cortex function could improve the ability ofindividuals to manage stressful events, thereby promoting the prevention ofhalitosis, pseudo-halitosis, and halitophobia. The present proposal couldcontribute to future empirical research.