Encyclopedia > Sinus cavity

  Article Content

Paranasal sinus

Redirected from Sinus cavity

The paranasal sinuses are eight (four pairs) air-filled spaces, or sinuses, within the bones of the skull and face. These are divided into subgroups that are named according to which bones they lie under;

The function of the sinuses is not entirely clear, but they may fulfill any or all of the following:

  • Decreasing the relative weight of the front of the skull
  • Helping to warm and humidify inhaled air before it reaches the lungs
  • Increasing resonance of the voice.

The paranasal sinuses are joined to the nasal cavity via small orifices called ostia. These become blocked relatively easily by allergic inflammation, or by swelling in the nasal lining which occurs with a cold. If this happens, normal drainage of mucus within the sinuses is disrupted, and sinusitis may occur.

All Wikipedia text is available under the terms of the GNU Free Documentation License

  Search Encyclopedia

Search over one million articles, find something about almost anything!
  Featured Article

... outside of the body. The urethra has an excretory function in both sexes, to pass urine to the outside, and also a reproductive function in the male, as a passage fo ...

This page was created in 25.5 ms