CH1-7 Dental Radiology Quiz Review

EFFECTIVE DOSE EQUIVALENT

used to compare risk of radiation exposure producing a biological response (microSv)

The extension arm allows ...?

the operator to position the tube head

COLLIMATOR

lead diaphragm used to restrict shape/size of useful beam

FILTER

aluminum absorbing material place in xray beam path

Xrays do not travel...?

convergent (crooked lines)

What is the xray injury sequence?

latent period, period of injury, recovery period

Thermionic emission is ..?

heating of cathode/filament to incandescence (red hot) to produce electrons

When you DECREASE Kvp, you...?

INCREASE exposure time

What is the greatest effect on sharpness?

movement

With the assessment of dental xrays, you do not have to include what?

assessing patient self care

Roentgen (R) is not ....?

an SI unit

ABSORBED DOSE

amount of energy deposited in any form of matter, hard or soft tissues (Gray, Gy, 100 rad)

What is the most sensitive to radiation in the body?

white blood cells (lymphocytes)

Xrays have the greatest ...?

penetrating power

Which cone is the least effective in minimizing radiation?

Pointed cone

LONG SCALE CONTRAST

LOW CONTRAST image, more shades of gray, densities between adjacent areas are small

When you press the xray button and hear an audible "beep" what is happening?

Xray is BEING generated (dead man exposure)

VELOCITY

speed of the wave

Why is radiolucent dark?

LESS DENSE, xray passage with little to NO resistance

Why does the operator need structural shielding?

To minimize radiation exposure

Black and white with many shades of gray is referred to as what?

Low contrast

DOSE EQUIVALENT

compares biological effects of various types of radiation absorptions (Sieverts, Sv, 100 rem)

The rectangular PID does what to the beam?

limits the beam

Polychromatic is composed of ...?

variety of energy wavelengths

EXPOSURE

to come in contact with (Coulombs per kilogram, C/kg)