We all have offensive breath at one
time of another. In most cases, offensive breath emanates from bacteria in the
mouth, although there are other more surprising causes. Until a few years ago, what the most doctors could do was to counsel patients with bad breath about oral cleanliness. Now they are finding new ways to treat the usually curable condition. Bad breath can happen whenever the normal flow of saliva slows. Our mouths are full of bacteria feeding on protein in bits of food and shed tissue. The bacteria emit evil-smelling gases, the worst of which is hydrogen sulfide. Mouth bacteria thrive in airless conditions. Oxygen-rich saliva keeps their numbers down. When we sleep, for example, the saliva stream slows, and sulfide-producing bacteria gain the upper hand, producing classic "morning breath". Alcohol, hunger, l A. its smell adds to bad breath B. it keeps offending bacteria from reproducing C. it kills some helpful bacteria D. it affects the normal flow of saliva 我来回答: 提交
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