Sinusitis is inflammation of the nasal cavity and the sinuses, which are air-filled spaces located primarily in the jaw above the upper teeth and in the forehead around the eyes.

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"When we chew and swallow, volatile molecules from the food go through the rear of the nasal cavity to the olfactory receptors in the roof of the nose, " says Richard Doty, director of the University of Pennsylvania's Smell and Taste Center.

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My 13 yr old golden, Lacie, was diagnosed with a fast growing fibrosarcoma tumor in her mouth that was so advanced it had already grown into her nasal cavity and was an extremely large mass located in the roof of her mouth.

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Each is lined with tissue called the mucosa, which secretes mucus continuously along hairy cells called cilia and out a tiny passageway called an ostium, through which the mucus drains into the nasal cavity and down the back of the throat, where it is swallowed (unless you blow your nose).

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