Please advise what is the best over-the-counter pain medication for a moderate to severe tooth ache?

See below. Forget over the counter pain medication it will not be effective seeing a dentist is what you need to do.
A dime. Drop a dime, call your dentist. Toothache means infected tooth. A pain pill will not cure an infected tooth. An antibiotic will slow the spread of infection for as long as you take it, but infection will come roaring back as soon as you stop. Any otc pain med may help take the edge off until you get to the dentist, but eventually infection will overpower the analgesic. See dentist now.