Dental insurance is tricky because you have to have a mechanism that prevents people from signing up, paying one month of premium (which often is in the $20-$40 range), getting a lot of work done, and canceling.
Most dental plans have a yearly benefits cap on claims, which can often be so low as to be the price of one root canal (or a few smaller procedures). And they seldom cover 100% of claims. It's more like having a dental discount plan that you pay for.
Not only that, but the amount that they'll cover slides down as the cost of the procedure slides up. If you're going for a cheap checkup and don't need anything special done, dental insurance struts up, cracks its knuckles and goes, "It's OK, I'll cover this one." If you have to have a root canal, dental insurance drops 50% of the cost on the ground and then bolts, never to be seen again.
