Base material (calcium hydroxide pastes) and cements exhibit approximately the same degree of radiopacity as:

A client with chronic sinusitis comes to the outpatient department complaining of headache, malaise, and a nonproductive cough. When examining the client's paranasal sinuses, the nurse detects tenderness. To evaluate this finding further, the nurse should transilluminate the:

a) frontal sinuses only. b) sphenoidal sinuses only. c) frontal and maxillary sinuses. d) sphenoidal and ethmoidal sinuses.

Which one of the following statements is true?

A) The perinatal period is from three days predelivery until 10 days after delivery. B) The perinatal period is from the time surrounding the birth of a child until 20 days after birth. C) The perinatal period is from the time surrounding the birth of a child until 28 days after birth. D) The perinatal period is from the time surrounding the birth of a child until eight weeks after birth.