Self-purchased dental plans almost never make sense. An insurance
company is not going to pay out more than it takes in in premiums. With
a large group, the insurance company knows that a certain percentage
will never even go to the dentist. People who buy individual plans
generally know they have significant dental needs. The only advantage is
if a dentist participates in the plan, the fee may be reduced. But when
you look at the yearly maximum benefits, deductibles and copays, it is
almost impossible to get over on an insurance company.
Look at your average yearly dental expenses over several years; then
look at the premium dollars you will pay for a year. Then look at the
benefit for (for example) that partial denture you say you need. Most
plans cover prosthetic devices like dentures at a lower rate (usually
50%) than they cover other services. See how much benefit you will get,
compared to your premium.