RAD. FINAL EXAM with correct answers 100%

diff btwn receptor holder and Beam alignment device - Correct Answers the RH only stabilizes the
receptor. the BAI stabilizes and helps align the PID to the receptor



which receptor holder is dispoabable - Correct Answers stabe bite block



what year were standards established for xray equip. - Correct Answers 1974



film base is made of ? how thick? and its function? - Correct Answers polyester plastic, 0.2 mm,
supports the emulsion



adhesive layer of film is located on which side? and purpose? - Correct Answers both sides of film,
attaches the emulsion to the base



the emulsion is composed of - Correct Answers homogenous mix of silver halide and gelatin.



the 2 types of silver halide are - Correct Answers AgBr (siliver bromide 80-90%) and AgI (silver iodide 1-
10%)



protective layer of film is? - Correct Answers a thin transparent coating over the emulsion to protect it
from manipulation / damage



describe silver halide crystals positioned behind an amalgam restoration ? or behind air space? - Correct
Answers amalgam -less energized bc they recieve less radiation. air space - there is less density so there
is more radiation recieved and crystals are highly energized



which is used in intraoral xray film? Double emulsion or single emulsion ? - Correct Answers double
emulsion (emulsion on both sides) bc it requires less radiation exposuire

,WHAT ARE 3 FACTORS AFFECTING FILM SPEED (board question) - Correct Answers 1. size of silv halide
crystals (larger is faster)

2. thickness of emulsion

3. presence of radiosensitive dyes



what are the tube side and label side of the outer film wrapping? - Correct Answers TUBE SIDE : "white
in sight" faces the teeth and tubehead and contains raised ID dot. LABEL SIDE has flap to open film
packet



F speed film requires ___ percent of the exposure time that D film used - Correct Answers 60%



optimal storage conditions for film are at what temperature and humidity level - Correct Answers temp
: 50- 70 degrees ........30 to 50 % humidity.



how does image sharpness compare with use of fast or slow speed films - Correct Answers FAST = less
sharp, big crystals. SLOW = more sharp, small crystals...... HINT TO REMEMBER : if a crackhead has large
crystals they are bouncing off the walls so fast and they lose their mental sharpness. if they have only
small crystals they wont be as hyper and will have more sharpness LOL



compounds that change when exposed to light or radiation are termed - Correct Answers halides



invisble part of stored energy on a film is called - Correct Answers latent image



is a screen film more sensitive to fluroescent light or to xrays? - Correct Answers flurescent light



what device transfers xray energy into visible light - Correct Answers intensifying screen



INCREASED mA results in - Correct Answers -INCREASED # OF XRAYS

-INCREASED DENSITY (darker image)



is duplicating film used intraorally or extraorally? - Correct Answers NEITHER!!!! its used by itself in a
dark room to make a copy of an exisiting radiograph. IT DOES NOT GET EXPOSED TO XRAYS!!!!!

, if exposure time increased how does it affect the NUMBER of xray photons - Correct Answers also
increases



INCREASED kV RESULTS IN - Correct Answers -xrays of HIGHER energy

-INCREASED denisty (darker image)

-LOW CONTRAST (more shades of gray)

-long scale contrast



increased exposure time results in - Correct Answers icreased density (darkness)



what is short scale and long scale contrast - Correct Answers SHORT SCALE = high contrast, very black
and white ..... LONG SCALE = low cont, many shades of gray



what 3 factors influence sharpnes - Correct Answers 1. FOCAL SPOT SIZE (smaller is sharper , think of a
needle being sharper than something bigger liek a pencil )

2.FILM COMPOSITION (smaller emulsion crystals are more sharp)

3. MOVEMENT (if pt moves image is blurry and not sharp)



what is Penumbra ? when is it found in images? - Correct Answers unsharpness / blurring of image
around edges. PRESENT IN EVERY IMAGE TO A CERTAIN EXTENT. but images with a small focal spot have
less Penumbra



what type of object receptor alignment minimizes distortion - Correct Answers being parallel



how is SUBJECT THICKNESS (size of the patient) related to density - Correct Answers -LESS SUBJ
THICKNESS = small patient = more density = darker image

-MORE THICKNESS = large patient, less density, lighter image



how is magnification affected by target-receptor (determined by length of PID) and object-receptor
(btwn tooth and film) distance? - Correct Answers -INCREASED TARGET RECEPTOR (longer pid) = less
magnification, INCREASED OBJECT RECEPTOR = more magnification.