Class I
Bilateral edentulous areas located posterior to the natural teeth
Class II
Unilateral edentulous area located posterior to remaining nautral teeth
Class III
Unilateral edentulous area with natural teeth remaining both anterior and posterior to it
Class IV
Single, but bilateral, edentulous area located anterior to the remaining natural teeth
No modification areas can be included in _____ arches
Class IV
Applegate-Kennedy Class V
Edentulous area bounded anteriorly and posteriorly by natural teeth, but in which the anterior abutment is not suitable for support
Applegate-kennedy Class VI
Edentulous area in which the teeth adjacent to the edentulous space are capable of total support of the required prosthesis