What serves as a baseline from which to track improvement or deterioration in the patient's condition?

When charting restorations, a PFM is the abbreviation for which occurrence?

porcelain finished material patient faints momentarily porcelain filling on mesial surface porcelain fused to metal crown

All of the following features are essential to a mobile radiographic unit EXCEPT

a. expandable 6-foot exposure cord. b. automatic exposure control with single field. c. dead-man type exposure switch. d. clear display of exposure factors.