The head and face contain a number of sinuses, open cavities that communicate with the upper airway. They function to warm and cleanse air before it travels down to the lungs. They may also help to reduce the total weight of the skull. In normal health, these sinuses cannot be appreciated on examination and cause no symptoms. Inflammatory states, in particular those caused by allergy or infection, produce symptoms and findings that may be detected during examination. Symptoms associated with sinusitis include: nasal congestion, nasal discharge, facial pain, fever, and pain on palpation of the maxillary teeth. The frontal and maxillary sinuses are the two that can be indirectly examined. Examination for sinusitis should include the following: