An internal sinus procedure for patching a perforation in patient's sinus membrane comprising the steps of (i) creating an opening in the sinus floor of a patient to expose the portion of the sinus membrane including the perforation, (ii) inserting a quantity of a sinus membrane patching material through the opening to a location adjacent the sinus perforation and (iii) laterally expanding and forcing the patching material against the sinus membrane to seal the perforation.