The nasopharynx and oropharynx merge into the larynx, which is protected by a trap door called the epiglottis.
Etiology of aspiration pneumonia The organisms involved in aspiration pneumonia are generally those colonizing the upper oropharynx and gut.
When air is inhaled (inspired), it passes through the nose and the nasopharynx or through the mouth and the oropharynx.
Oropharynx-One of the three regions of the pharynx, the oropharynx is the region behind the mouth.
Air breathed in through the mouth travels through the oropharynx, which also carries swallowed food, water, and salivary secretions through the food tube (esophagus) and then into the stomach.