Just take all of the money you'd otherwise spend on dental care and put it into a savings account or FSA.
I've never seen a dental insurance plan that actually makes financial sense. Most of them place significant limits on expensive and unlikely care, and cover routine care with little or no cost sharing. Insurance is a highly inefficient way to pay for expected expenses.
Yes, the only downside I can think of is if you have an HSA (which anyone that can afford max out of pocket limit should), then you generally cannot have FSAs also unless they are Limited Purpose FSAs and then it gets too complicated for my tastes. I generally do not like the concept of FSAs period, being employer owned, and having to use up funds by the end of the year and all.
I've never seen a dental insurance plan that actually makes financial sense. Most of them place significant limits on expensive and unlikely care, and cover routine care with little or no cost sharing. Insurance is a highly inefficient way to pay for expected expenses.