Test your basic knowledge |

Radiology 2

Subjects : health-sciences, radiology

Instructions:

Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can study here.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. What is the area of the skull that is in focus on a pano

2. What are automatic processors faster than manual processing?
MA & time
B/c of its stability to produce a large volume of radiographs in a short amount of time
20 min
GBX - 2

3. What is the major use of cross sectional occlusal radiograph
KVp
Do not suggest gagging - emphasize - use power of suggestions - apply distractiong techniques - give patient breathing instructions - reduce tactile stimuli - being exposures in the ant. region - place image receptor firmly and expertly - confuse the
Provides more info. about the location of tori - impacted and malpositioned teeth and the calcification of soft tissues
Absorb long wavelengths / soft radiation

4. What is the purpose of replenishing the developer solution
#3
The less the patient is exposed - the less the operator is exposed
Maintain acidity & alkalinity & prevent oxidation -
All of the ant. teeth will appear blurred and narrowed in width

5. Size film used for PA's on adults
7 1/2 or 15 watt
Periapical examination - paralleling technique
Dentsply rinn stabe - BAI - dental SUPA
#2

6. A properly exposed film appears completely black. when was is exposed to white light
Images conditions of the teeth and supporting structures when a larger area than a PA is needed; provides more info. than a PA about the alveolar crest and apical areas
Original packaging -area sheilded from radiation -50-70 degrees F
Before fixing
Overexposure -overdevelopment -developer is too strong -not enough fixation -exposure to white light -improper safelighting

7. You process a set of BW's in the automatic processor. three of the BW's are of good quality - but fourth is completely blank. What probably caused this?
Filters placed in PID after tubehead production
No exposure to x-rays - electrical failure - malfunction of x-ray machine - or processing errors
Original packaging -area sheilded from radiation -50-70 degrees F
Clear/blue in the area of overlap b/c fixer will not remove all crystals

8. When interpreting radiographs - you notice a radiopaque extension or spur off the proximal surface of #30. What do you think this is?
The mental ridge
1/5 exposure time for edentulous
#2
Time b/w exposure and 1st clinically observable symptoms

9. in which pericapical projection will the mental ridge be visible
Rapidly producing cells are more sensitive to radiation
Cosmic - naturally occuring radiation from earth - radiation for radioactive materials
Mandibular lateral/central
Reduces the exposed silver halide crystals to black metallic silver

10. How often should developing solutions be changed
5(n-18)
Every 4 weeks
Depends on the needs of the patient - established after intraoral exam
No exposure to x-rays - electrical failure - malfunction of x-ray machine - or processing errors

11. which radiographic technique records the most accurate image of crowns - roots - and supporting structures in a selected area?
1/3-1/2
Periapical examination - paralleling technique
Periodically examining cassettes and intensifying screens; extra oral cassettes should be checked for warping and light leaks
detect pathological lesions -establish position of mental foramen -establish position of mand canal -determine quality & quantity of alveolar bone present

12. What Size film is 2 1/4 x 3
Premature contact with developer
50 mSv or 5 REM
No. 4
The most distal tooth should be captured in full as well as a few mm of bone level behind the most distal tooth

13. Mand premolar anatomy
Mental foramen - mental ridge - mand canal
Insufficient vertical angulation
Scatter/secondary radition
Periodically examining cassettes and intensifying screens; extra oral cassettes should be checked for warping and light leaks

14. when viewing a radiograph - the tooth looks normal in size and shape; However - there is a large blank space at the incisal edge and the apices are missing. What caused this error
Large blank space is due to reversed image error or chemical contamination - missing apices is due to inadequate VA
Thyroid collar - lead and lead-equivalent sprons are availaable with or without an attached thyroid collar
Perpendicular to the tooth and film
Reg. replenishment and changing out expired solutiong with fresh chemicals at reg. intervals; monitor strength of chemicals on a daily basis

15. What equation is used to calculate the accumulated MPD
Rapidly producing cells are more sensitive to radiation
GBX - 2
5(n-18)
Mandibular lateral/central

16. What is the base of dental film composed of?
Blue tinted polyester acetate
Not as sharp and detailed as the intraoral image
Max. sinus - zygoma
Filament

17. What is the emulsion composed of?
Gelatin and silver halide crystals
Eyewear - mask - and gown
Step-wedge or test film
Scatter/secondary radition

18. What projection would you take for a patient complaining of pain in the lower left molar area
Left molar PA
Lead
Duplicate - which will go to the insurance comp.; office keeps best copy
Lateral cephalometric

19. How does radiation effect cells
Mental foramen - mental ridge - mand canal
Ionization
Rectangular collimations
Remove silver

20. Size film used for BW on adults when only one film is taken on each side
#3
Focal spot
The mental ridge
Remove silver

21. What is characteristic radiation
Cancer - cateracts - embryologic defects - genetic mutations - low birth weight
A form of radiation originating from an atom following removal of an electron or excitation of an atom
Reduce size and shape of beam
Not centered on sensor

22. How does resolutiong and detial of a panoramic radiograph compare with that of PA's and BW's
Decrease kVp by 15 and double exposure time = 10 mA 60 impules 75 kVp
Not as sharp and detailed as the intraoral image
On the back side of the tori
Sterilize film holder devices or discard disposable image receptor holding devices

23. What is added filtration
#3
Rapidly producing cells are more sensitive to radiation
Filters placed in PID after tubehead production
Method should be compensated for bisecting or paralleling

24. What is the ADA approved method of mounting dental radiographs
1/4 as intense
Labial
15 impulses
On the back side of the tori

25. What controls the speed with which the electrons travel from the cathode to the anode
Lighter image - patient exposed to larger beam which will increase exposure
Cancer - cateracts - embryologic defects - genetic mutations - low birth weight
Mandibular lateral/central
KVp

26. What is the proper patient position for BW's?
Clear/blue in the area of overlap b/c fixer will not remove all crystals
1/4 as intense
Left side
Ala-tragus line is parallel to the floor

27. According to the principles of shadow casting - preferred object-film distance
Part that was fixed but not developed would be clear
After 2-3 min of fixing if needed
As close as possible
1/3-1/2

28. What size bulb is used in safelight
7 1/2 or 15 watt
Cracking of the emulsion caused by excessive temp diff. b/w any darkroom solutions
As close as possible
Move farther from the radiation

29. When mounting dental radiographs - What is the best way to differentiate max and mand films?
extraoral film
Reduces the exposed silver halide crystals to black metallic silver
Blue tinted polyester acetate
max teeth are longer - max molars have 3 roots - mand molars have 2 roots - most roots curve toward the distal - occlusal plane is straight or curved slight towards distal

30. What is the annual MPD for pregnant dental assistant
5 mSv or .5 REM
Clinical exam
max teeth are longer - max molars have 3 roots - mand molars have 2 roots - most roots curve toward the distal - occlusal plane is straight or curved slight towards distal
Mandibular occlusal

31. How long are films fixed
Cracking of the emulsion caused by excessive temp diff. b/w any darkroom solutions
The mental ridge
Images conditions of the teeth and supporting structures when a larger area than a PA is needed; provides more info. than a PA about the alveolar crest and apical areas
10 min (dbl the development time)

32. which projection is used to view sinuses
#2
Coulombs/kilogram(C/kg) & Roentgen (R)
PANO
Produced by internal barriers in tube head (ex: glass and insulating oils)

33. What parts of the x-ray machine are included in the cathode circuit
Ala-tragus line is parallel to the floor
Cathode - filament - focusing cup
1/4 as intense
DEHNR

34. What film would be used to locate a foreign body in the bucco-lingual relationship
DEHNR
Occlucal
All of the ant. teeth will appear blurred and narrowed in width
1/4 as intense

35. How does kVp affect patient exposure
Not as sharp and detailed as the intraoral image
X-ray and heat
No. 1
Higher kVp = low exposure

36. desired thickness of lead apron
Blank or clear (takes all of the crystals off)
.25 mm
Located on the tooth surface that contacts the adjacent tooth
PANO

37. What type film is faster - intraoral or extraoral
Occlucal
The wave length will be shorter - the quality and energy of the beam will be higher and the contrast will be lowe. - the image will also have a higher density
Extra oral
Filters placed in PID after tubehead production

38. What types of cells must be effected in order for mutation to occur
Incorrect horrizontal angulation
Genetic cells
X-rays that have gone thru an object and are now a newer weaker beam
Ionization

39. What would cause the radiographic image to be blurred
#0
Removes the unexposed silver halide crystals
Lateral cephalometric
Movement caused by the patient - slippage of the image receptor - or vibration of the tube head

40. What happens in the developer
As far as practical
Perpendicular to the film - parallel to the bite portion of the stabe
Reduces the exposed silver halide crystals to black metallic silver
5 min

41. What is the earliest sign of radiation exposure
Erythema
Rectangular collimation
Aluminum
Insufficient or improper washing

42. What is the name for the part of the target that is struck by electrons
Original packaging -area sheilded from radiation -50-70 degrees F
Enamel - dentin - and bone
Long-term dose
Focal spot

43. if the source-object distance is cut from 16 to 8 - What must be changed to compensate
Dark film is from over exposure and improper packet placement for strange looking teeth and not being able to determine What film is
10 min (dbl the development time)
The most distal tooth should be captured in full as well as a few mm of bone level behind the most distal tooth
Method should be compensated for bisecting or paralleling

44. when manually processing dental film - you notice the temp. has gotten warmer as the day progressed. How should the developing time be changed?
2.75 inch
Part that was fixed but not developed would be clear
Higher temp. increases film fog - so radiographer should consult a time-temp. development chart to adjust developing time appropriately; developing time will decrease
20 min

45. What determines the speed of dental films?
Beam is perpendicular to the imaginary line that bisects the angle formed by the long axis and the film
Size of crystals - thickness of emulsion - radiosensitive dyes
The wave length will be shorter - the quality and energy of the beam will be higher and the contrast will be lowe. - the image will also have a higher density
Periodically examining cassettes and intensifying screens; extra oral cassettes should be checked for warping and light leaks

46. How long does the first rinse last
take 14 radiographs -omit the BW -paralleling should be technique of choice -panoramic might be better than FMS
Aluminum
Tori
20 seconds

47. What causes teeth to appear very short and distorted
Patient positioned too far foward in the focal trough
Excessive VA w/ PID positioned too steep enough away from zero degrees
Size of crystals - thickness of emulsion - radiosensitive dyes
Increase the area of radiation exposure

48. According to principles of shadow casting - How should the central beam be directed
Perpendicular to the tooth and film
Positioning the arches too far foward
Rectangular collimation and fast film speed
Rectangular collimation

49. How long does film stay in the developer
The mental ridge
Patient's name - date - and other pertinent info
No exposure to x-rays - electrical failure - malfunction of x-ray machine - or processing errors
5 min

50. What radiographs are used to locate a salivary stone in the submandibular duct
Erythema
Mandibular occlusal
Invisible image (remains like this until film is processed)
Patient positioning