D2150 Amalgam - two surfaces, primary or permanent No Tooth and surface designations required. Allowance includes polishing. D2160 Amalgam - three surfaces, primary or permanent No Tooth and surface designations required.

Code D2391 (one-surface posterior resin-based composite) explicitly states that it should be “used to restore a carious lesion into the dentin.” The rationale for the requirement that the lesion extends into dentin can be questioned.