ANATOMY & PURPOSES OF THE SINUSES
The bones of the face and skill near the nose contain four pairs of air-filled pockets, which are called the paranasal sinuses. The paranasal sinuses include the following types of sinuses:
- A maxilarry sinus in each cheek
- Between six and tweleve ethmoid sinuses on each side of the nose between the eyes
- A frontal sinus on each side in the forehead
- A pair of sphenoid sinuses behind the ethmoid sinuses
Each sinus has an opening, called an ostium, which connects it to the nose.
The sinuses, except for the frontal sinuses, begin in the fetus as pea-sized air pockets that grow through childhood until they are roughly walnut sized.
The sinuses lighten the skull or improve our voices, but their main function is to produce a mucus that moisturizes the inside of the nose. This mucus layer protects the nose from pollutants, micro-organisms, dust and dirt. Tiny hair cells called cilia move the layer of mucus slowly backward into the throat, where it is swallowed.