Does Epsom salt actually do anything? What are the side effects of Epsom salt? How often can you soak in a bath with Epsom salt? Does salt water work for a toothache? Epsom salt is a compound made of magnesium sulfate that carries a potential host of benefits.
Gargling with Epsom salt also works as a germicide to keep your mouth clean in.
So, going by your question, the suggestion would be to give it a try. But do take the tooth-infection-cure claim with a pinch of salt (no pun intended). Gurgling with Epsom salt water may reduce inflammation and pain for minor toothache , but do not depend on it heavily and expect your. First put a cople of tablespoons of the Epsom salt water in your mouth then create suction on the offending tooth.
It will hurt worse for a few seconds when you get it right, hold the suction as long as you can then stop and spit the epsom salt water out. It is believed that one of the worst possible pain that one can be afflicted of are toothaches. They can be severe enough to get your head and ears throbbing along with the excruciating toothache and set you completely off gear. Good description of the symptoms.
It might help to know what the fish is.