For the purpose of examining the significance of a pain focus in the maxillary air sinus denervation of the mucosa of the sinus by transantral maxillary nerve section was performed. The material comprises 20 patients with pain in the distribution of the infraorbital nerve and previous disease of the relevant sinus. All patients had been treated previously without any benefit from peripheral surgery of the infraorbital nerve. Only 20% had any benefit of the proximal avulsion for more than three months. It is concluded that impulses from the mucosa of the maxillary sinus do not play any part in the occurrence or persistence of facial pain in this highly selected material.