Radiation Health & SafetyQuestion 7 of 100
A practice replaces its round position-indicating devices with rectangular collimation. What is the main benefit to the patient?
a.The exposed tissue area is substantially reduced, lowering patient dose
b.The exposure time can be doubled without added risk
c.Vertical angulation errors are eliminated
d.The lead apron is no longer needed
Explanation
Rectangular collimation restricts the beam to approximately the size of the image receptor, cutting the irradiated tissue area and patient dose by roughly half or more compared with a round cone. It does not justify longer exposure times and has no effect on vertical angulation, which depends on operator technique. Collimation reduces dose but does not replace the lead apron where shielding is recommended.
Law Reference: NCRP Report No. 145: Radiation Protection in DentistryPractice all 100 questions free — no signup required.
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