Editing Middle ear (section)

==Clinical significance==
The middle ear is hollow in the tympanic cavity and Eustachian tube. In a high-altitude environment or on diving into water, there will be a pressure difference between the middle ear and the outside environment.  This pressure will pose a risk of bursting or otherwise damaging the tympanum (eardrum) if it is not relieved. If middle ear pressure remains low, the [[eardrum]] (tympanic membrane) may become [[Tympanic membrane retraction|retracted]] into the middle ear.{{cn|date=November 2020}}  One of the functions of the [[Eustachian tube]]s that connect the middle ear to the [[nasopharynx]] is to help keep middle ear pressure the same as air pressure. The Eustachian tubes are normally pinched off at the nose end, to prevent being clogged with [[mucus]], but they may be opened by lowering and protruding the jaw; this is why [[yawn]]ing or chewing helps relieve the pressure felt in the ears when on board an aircraft. [[Eustachian tube]] obstruction may result in fluid build up in the middle ear, which causes a [[conductive hearing loss]]. [[Otitis media]] is an inflammation of the middle ear.