You save money by using an in-network dentist because dentists in the Delta Dental network have agreed to charge lower fees for services. If you use a Delta Dental PPO dentist, your diagnostic and preventive services are covered at 100% with no deductible. In-network dentists file the claim forms for you and you are not required to pay the entire bill in advance. You may, however, be required to pay your portion of the covered services at the time of initial service and the dentist will bill Delta Dental for the balance.