The dental examination is not a "review".  What you are describing is called "a loss-leader" in retail.  Do you know the cost of the service that you received?  Do you care?  
Go to Mexico where that "work" will done without health regulations, exposing you to potential infection; materials and products that are likely not approved for use in Canada and US; and personnel who are likely unlicensed.  
As Oscar Wilde said, "Nowadays people know the price of everything and the value of nothing."