salt will make silver chloride, thats why not to use it together.
you really should get some xylitol. in fact you should get some inulin too and use the two together as a prebiotic. the fact that you have such a bad sinus infection shows you have a bacteria imbalance. this is from the use of Antibiotics , which is why you are still having to rely on an antibiotic, in this case silver. and while this is much better than going to a doc, it is not ideal.
make sure your probiotic contains beneficial strains of strep as well as the usual lacto and biffido. after you have had success with your silver treatments, wait a week and then start with the pro and pre biotics. the good bacteria compete with the bad bacteria so they can never get a foothold again. this is how nature intends us to be.