Need helping choosing a dental insurance plan Aetna DMO or PPO?

I am being offered two options at work for dental insurance. Aetna DMO and Aetna PPO The DMO will be $24 a month for the family, while the PPO will be around $56 In terms of benefits, the DMO is better, there is no deductible, no annual maximum, and most services are covered at either 100 , 90 or 80% The PPO plan has a $150 family deductible, and $2500 annual maximum per person. Services are covered at 100/80/60% depending on the type. On the surface it seems the DMO is the logical choice, however, much like an HMO there are downsides. The number of dentists available in my zip code for the DMO is 3, compared to the PPO which has 28. The DMO does not have out of network benefits, while the PPO does. The PPO does not require referrals for specialists, which the DMO does. I am really having a hard time choosing. We don't use dentists that much, we have our cleanings, an occasional cavity, and rarely a root canal. I don't want to simply go with the cheapest option necessarily, so any input would be great! Especially if you have experience with an Aetna PPO/DMO
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This is how I see it. If you are blessed with only 1 cavity in 10 years, choosing Dental HMO is better. Why pay more, when you don't really need too.
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