how do you mean 'overcharging'?  Dental treatment is a private business in Canada, each dentist can charge any price he likes, and there can be wide variance between provinces and individual dentists.  The free market sets the price, which means it is not overcharging but instead you have the choice to shop around.  And it is telling how non-expert patients with no dental degree think the procedure recommended for them is unnecessary .. so they choose to not get it and their tooth breaks or gets an excruciating toothache