Chapter 6 Questions and Answers
Graded A+
What part of the X-ray machine produces radiation?
✔✔The X-ray tubehead
Why is a longer PID preferred in dental radiography?
✔✔It produces a more parallel X-ray beam and reduces image distortion
What is the purpose of a step-down transformer in an X-ray machine?
✔✔To decrease voltage to heat the filament and generate electrons
Why is a lead apron used during dental X-rays?
✔✔To protect the patient from unnecessary radiation exposure
What is the role of the exposure timer?
✔✔To control the duration of X-ray production
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,How does milliamperage (mA) affect the X-ray beam?
✔✔It controls the number of X-rays produced
Why should a rectangular collimator be used instead of a round one?
✔✔It reduces patient radiation exposure by limiting the beam size
What happens if exposure time is increased?
✔✔The X-ray image appears darker
Why is fast film or a digital sensor preferred in dental radiography?
✔✔It reduces radiation exposure to the patient
What is the main purpose of the cathode in the X-ray tube?
✔✔To produce and release electrons
How does increasing the distance between the X-ray source and the patient affect image
sharpness?
✔✔It improves image clarity and reduces magnification
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, Why must dental X-ray machines be regularly tested?
✔✔To ensure consistent image quality and maintain safety standards
What is the function of insulating oil in the tubehead?
✔✔To prevent overheating of the X-ray tube
What does a bitewing X-ray show?
✔✔The crowns of upper and lower teeth to detect cavities
How does collimation reduce scatter radiation?
✔✔By restricting the size of the X-ray beam
What happens if kilovoltage (kVp) is too low?
✔✔The image appears lighter with poor contrast
What is the purpose of the anode in the X-ray tube?
✔✔To convert electrons into X-ray photons
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