Participants insured with a dental PPO insurance plan are responsible for paying their deductible before receiving any reimbursement. One of the key differences between dental HMO insurance and dental PPO insurance is that DPPOs usually allow dentists to spend more time with insured patients. Dentists in dental HMO insurance plans are expected to see a certain number of patients, so some dentists have been known to rush through dental appointments. A PPO dental insurance plan consists of numerous dentists that sign up to join a network insurance system or group with hopes that they will have many patients to service. When subscribers join a PPO dental plan, they benefit from lower out-of-pocket costs when they see one of the network dentists.