Sinusitis is frequent disease of the nasal cavities. It can be result from different agents (bacteria, viruses, micelles). In the autumn and winter is most frequent. The progress and the chronification of sinusitis there are many reasons, like specific characteristic of the nasal cavities in everyone, the stage of the immune system in human. The presence of polypus in the nasal cavities is a favourable factor, also the difficult drainage of the secretion. Sinusitis represents acute or chronicle inflammation of the nasal cavities. The inflammatory process passes from the nasal cavities to the sinus cavities. Because of trauma causes usually the infection of sinus cavities, dental granuloma 's rupture may cause infection of sinus cavities. Sinusitis can be an acute ot chronicle disease, with a continuation in the time, with periods of symptomatic fading or aggravation. When the inflammation and the purulent process are in continuation more than three month, there is a chronicle sinusitis.