elindra, here's what I got from Wikipedia :
"Transient bad breath is a very common temporary condition caused
by such things as oral dryness, stress, hunger (ketosis), eating
certain foods such as garlic and onions, smoking, and poor oral
hygiene. Morning breath is a typical example of transient bad
breath. Chronic bad breath is a more serious and highly persistent
condition affecting up to 25% of the population in varying degrees.
It can negatively impact the individual's personal and business
relationships, leading to poor self-esteem and increased stress.
This condition is usually caused by persistent overpopulation of
certain types of oral bacteria, primarily streptococcus mutans, and
requires specialised treatment. Xerostomia (dry mouth syndrome)
will increase bad breath problems.
"Fetor hepaticus is a type of bad breath caused by chronic liver
failure. It has been said to resemble "the smell of a freshly
opened corpse."
