Thanks for putting up your question on Just Answer.
Since your dental
hygienist has ruled out any dental/periodontal
issues, I strongly suspect am underlying sytemic problem.
About 85% of bad breath cases result from oral conditions. A variety of systemic and extra-oral conditions account for the remainder. Bad breath is caused by volatile sulfur compounds or VSC’s that are produced by anaerobic bacteria in your mouth.
Reflux of stomach acids into the esophagus and as high as the throat is known as gastroesophageal refux and can cause halitosis ( bad breath).
This can be confirmed by tests like barium esophagram, pH monitoring, and endoscopy.
Bad breath or halitosis can be caused by nasal or throat conditions like sinusitis; chronic nasal airway obstruction (such as which might occur with a deviated nasal septum) chronic tonsillitis particularly when associated with deep crevices known as crypts which accumulate partially digested food
Halitosis may also be be related to odors which are excreted in expired air.Certain drugs release odors into expired breath from the lungs. All of these ingested substances are metabolized usually in the liver with breakdown products travelling in the blood stream where they eventually reach the lung tissues where a gas exchange occurs.
Systemic illness can also manifest with bad breath, like ( commonly)uremia (kidney failure)
I suggest a consultation with a physician to discuss all these causes.
Hope this answers your question. Feel free to contact me again for more information.
I wish you a speedy recovery !!!
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