​In order to save hundreds of dollars while travelling, get another credit card.  Credit card companies charge you a foreign transaction (FX) fee on every purchase you make while travelling, or for any transaction occurring outside of your home country.  These fees can cost you as much as an additional 4% for every purchase!
For dental travelers in particular, who may spend multiple thousands of dollars on their dental care and travelers expenses, 4% can add up to hundreds of dollars.  Visa/MasterCard charge 1% and your bank that issues your credit card can charge you an additional 1-3% on top of Visa/MasterCard’s FX fees.

For example, if you spend $10,000 while travelling, you will pay an additional $400 to your credit card company for the privilege of using your card.

Make sure that you have a credit card that doesn’t charge foreign exchange fees before you travel overseas.

Credit cards that do no charge foreign transaction fees

UK
Australia
Canada
Sadly there are no credit cards which do not charge foreign exchange fees :(

United States