There’s no doubt about it – it’s extremely important to purchase dental insurance for you and your family. Just as you need medical insurance to help cover the costs of routine checkups and catastrophic illness, you need dental insurance to help pay for your exams, cleanings and any other dental procedures that you and your family may need now or in the future. Remember that healthy teeth and gums are related to good overall health, so it’s vital to maintain good oral health for you and your family. When shopping for the right dental plan, make sure know the differences between the two major types of dental insurance: HMO and PPO.
PPOs (Preferred Provider Organizations)
Generally speaking, a PPO plan gives the insured person more flexibility with regard to choosing a dentist. Usually, the insurance company provides a list of “preferred providers.” The insured person has the choice of either using a dentist on the preferred provider list or using one that is not included on the list. PPOs are typically a bit more expensive than HMO plans because they offer this flexibility.

HMOs (Health Maintenance Organizations)
If you belong to an HMO, you must choose a dentist that has been preapproved by your insurance company and appears on the company’s preferred provider list. In most HMO plans, services provided by a dentist who is not a preferred provider will not be covered by the insurance company. HMO plans are typically somewhat less expensive than PPOs because they’re more restrictive with regard to your choice of dentists.
Source: http://www.ihealthcoalition.org/dental-insurance/ppo-dental-plans/
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