
Generally dental offices have a fee schedule, or a list of prices for the dental services or procedures they offer. Dental insurance companies have similar fee schedules which is generally based on Usual and Customary dental services, an average of fees in your area. When a dentist signs a contract with a dental insurance company that provider agrees to match the insurance fee schedule and give their customers a reduced cost for services, this is considered an In-Network Provider or Participating Provider network (PPO). Depending on your specific plan, if you seek an Out-of-Network or Non-Participating Provider, any difference of fees will become the financial responsibility of the patient unless otherwise specified in your dental policy. Some dental insurance plans may have waiting periods. This is a period of time before certain benefits will be covered. Generally set in place when you are a new enrollee or seek out an independent plan outside of an employer or group policy.
(Source:Wikipedia)