Thanks for putting up your question on Just Answer.
About 85% of bad breath cases result from oral conditions. A variety of systemic and extra-oral conditions account for the remainder.
the cause in your case I think lies somewhere else in the body.
I advise you to get :
Nasal or pulmonary foreign bodies, bronchiectasis,anaerobic lung abscess
,food trapped in a Zenker's diverticulum,gastroesophageal reflux disease (GERD) and hiatal hernia
all ruled out.
Severe dieting can also lead to halitosis. Dieters may develop unpleasant "fruity" breath from ketoacidosis, the breakdown of chemicals during fasting.
A worse odor through the nose suggests nasal or sinus etiology. Similar odor through both nose and mouth suggests a systemic or pulmonary cause.
Bot***** *****ne : Get all the above causes checked out !
Hope this answers your question. Feel free to contact me again for more information.
I wish you a speedy recovery !!!
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