thats not the way this works. Paying $20k over a lifetime vs an up front $20k payment means the up front $20k payment also includes the opportunity cost of the interest made - your up front payment of $20k is much more valuable than $20k over 60 or 70 years. That same $20k might be a large part of a downpayment on a mortgage and you'd get back many more times the value than if you spent it on your teeth all at once.
Sure, but you're literally throwing an opportunity to own property which historically is the best possible return to get preventive work done on your teeth. And not all healthcare is the same, so I'm not even sure dental costs are rising at the same rate as "healthcare".
