Yes they are air pockets inside the skull, that’s why when you clean it you can just push water through one nostril and it will come out on the other, because it fills the sinus. Also, sometimes you can feel you teeth too sensitive because you have something on the sinus above them
no no, it’s like the photo bellow. My doctor recomended because there is a button that allows the water to go on the necessary speed only, that way it doesn’t allow water to go to your ears and give you an infection.
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