This is a very good question and many people have faced this problem as well. The truth is, you will not have to pay extra if there is a minor problem after the treatment. Almost all medical services make sure that you do not face any post treatment issues, but if you do, the hospital will themselves take care of all the charges of making things right and getting you the right treatment you initially paid for. However, it is best to discuss this with the provider and get written confirmation before booking.