“…Although systemic disease, decreased saliva secretion, smoking, ovulation, and an empty stomach can cause halitosis, the most common causes are related to various factors in the oral cavity8) . Protein compounds from oral epithelial cells, saliva, gingival crevicular fluid, blood, and residual food are metabolized mainly by gram-negative anaerobic oral bacteria, thereby producing volatile sulfides compounds, volatile nitrogen compounds, volatile fatty acids, acetone, and acetaldehyde, which induce halitosis9,10) .Despite the absence of bad breath, there may also be difficulties in interpersonal relations due to halitophobia.With the increase in social activities, the consumption of oral cleaning products for deodorization is further increasing. Poor oral hygiene, dental caries, periodontitis,xerostomia, and infectious disease such as oral candidiasis can cause halitosis.…”