All implant treatment depends upon a high level of clinician training and experience.Much of the cost of treatment is not system dependent but relates to clinical time and laboratory expenses.For example,Albreksson et al.(1986) proposed the following criteria for minimum success:

    1,An individual,unattached implant is immobile when tested clinically.

    2,Radiographic examination does not reveal any peri-implant radiolucency.

    3,After the year in function,radiographic vertical bone loss is less than 0.2 mm per annum.

    4,The individual implant performance is characterized by an absence of signs and symptoms such as pain,infections,neuropathies,paraesthesia,or violation of the inferior dental canal.

    5,As a minimum,the implant should fulfill the above criteria with a success rate of 85% at the end a 5-year observation period and 80% at the end of a 10-year period.