There is no reason to be frightened. The dentist did not expect to make money on the windfall inevitable tooth decay. The fact is, if you are going to eat candy, often grabbing so much better for your teeth than rationing.
Slowly snacking on Halloween Candy every few hours, days, keep Your teeth enamel corroding bathed in acid, a byproduct of bacteria eat sugar and other carbohydrates in your mouth. This leads to dental caries or cavities.
For example, as far as oral hygiene goes, it is better to eat candy five at once than to eat one every few hours. In the first scenario, the acid will build in your mouth, but Your saliva will naturally neutralizes this for an hour or more. And then that acid is gone. In the second scenario, you are constantly revealing the teeth to sour the whole day, too much for saliva to wash away.
Gorging also better, because it is more likely to be followed by brushing. People, and especially children, are less likely to brush their teeth after every candy bar, especially if they are not at home.
The candy is not always the worst for your teeth, anyway. The factors that really cause cavities are sticky and acidity. Potato chips and pretzels, for example, the worse offender than chocolate, as it is cooked carbohydrates attached to teeth-gives the mouth bacteria something to feast again and thus produce more acid.