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 reticulation
Mand canal - external oblique ridge - beg. of ramus
DEHNR
The less the patient is exposed - the less the operator is exposed
Cracking of the emulsion caused by excessive temp diff. b/w any darkroom solutions

2. How is vertical angulation established with the bisecting technique
GBX - 2
Beam is perpendicular to the imaginary line that bisects the angle formed by the long axis and the film
Increased focal spot size - decrease source-object distance - & increased object-film distance
Blank or clear (takes all of the crystals off)

3. in which pericapical projection will the mental ridge be visible
Nerve - brain - muscle
Mandibular lateral/central
2.75 inch
10 min (dbl the development time)

4. What is the major diff. b/w particulate and electromagnetic radiation
particulate radiation: made of protons - neutrons - electrons and alpha and beta particles; has mass -electromagnetic radiation: made of photons; no mass
White blood cells - red blood cells - immature reproductive cells - epithelial cells - connective tissue cells - bone cells - nerve cells - brain cells - muscle cells
#0
10 min (dbl the development time)

5. How does exposure time for children compare to that of an adult
2.75 inch
All of the ant. teeth will appear blurred and narrowed in width
max molars have 3 roots - mand have 2 roots
1/3-1/2

6. What film is used to diagnose interproximal decay
BW
1/6th of a second
Photostimuable Phosphor Plate aka storage phosphor system -indirect digital imaging -captures analog data then processed in a laser scanning device -light is then converted into electrical signal that the computer uses to create the digital image
No exposure - or fixer before developer

7. What factors affect the sharpness of the radiographic image
8-16 inches
Focal spot size - target-image receptor distance - object-image receptor distance - motion - screen thickness - screen-film contact - and crystal/pixel size of intraoral image receptors
No. 2
invisible -travel in straight lines -no mass/weight -travel and speed of light -no charge -interact w/ matter causing ionization -can penetrate opaque tissues and structures -can effect photographic film emulsion -can effect biologic tissue

8. What is the best method of protecting the thyroid gland from radiation?
Thyroid collar - lead and lead-equivalent sprons are availaable with or without an attached thyroid collar
Mand canal - external oblique ridge - beg. of ramus
Failed safelight test - suggesting that the safelight conditions in the darkroom are fogging the film
2.75 inches

9. What is the purpose of collimation
Reduce size and shape of beam
Chronic low-level exposures/long term dose; causing cancer - cataracts - low birth weight - genetic mutations - and embryological defects
Every 4 weeks
Premature contact with developer

10. According to principles of shadow casting - How should the film be placed in relation to the tooth?
Cracking of the emulsion caused by excessive temp diff. b/w any darkroom solutions
Periapical examination - paralleling technique
White blood cells - red blood cells - immature reproductive cells - epithelial cells - connective tissue cells - bone cells - nerve cells - brain cells - muscle cells
Parallel

11. What radiograph is used to sHow contrast in soft tissues
Thyroid collar - lead and lead-equivalent sprons are availaable with or without an attached thyroid collar
Old or contaminated processing solutions -exposure to chemical fumes -faulty safelight -scatter radiation
As low as reasonably achievable
MRI

12. What would happen to a film that is placed in the fixer prior to development
Periapical examination - paralleling technique
#0
Blank or clear (takes all of the crystals off)
Overexposure -overdevelopment -developer is too strong -not enough fixation -exposure to white light -improper safelighting

13. Mand central anatomy
Insufficient or improper washing
D - E - F
Genial tubercles - lingual foramen
No. 1

14. What exposure would be useful in identifying salivary stones in the submandibular gland
Mand occlusal
Perpendicular to the tooth and film
Extra oral
Remove silver

15. What control factors effect contrast
No exposure to x-rays - electrical failure - malfunction of x-ray machine - or processing errors
Gray & Rad
KVp
Periapical

16. What is the annual MPD for pregnant dental assistant
locate retained roots -locate unerrupted or impacted teeth -evaluate for diseases and lesions -locate foreign bodies -reveal presence of salivary stones (sialothiths) -aid in evaluating fractures -size and shape of tori -aid in examining patients wit
5 mSv or .5 REM
Blank or clear (takes all of the crystals off)
68 degrees F

17. What would cause a film to be too light
underexposure-underdevelopment -depleted developer solution -excessive fixation (takes all crystals off)
Insufficient or improper washing
X-rays that have gone thru an object and are now a newer weaker beam
Negative

18. How should the frequency of radiographic exposures be determined
Not as sharp and detailed as the intraoral image
Reduces the exposed silver halide crystals to black metallic silver
Depends on the needs of the patient - established after intraoral exam
Film badges

19. What Size film is 2 1/4 x 3
No. 4
Mandibular occlusal
Erythema - vomitting - nausea - hemorrage - diarrhea - hair loss
Density

20. 3 film holding devices used for bisecting
Dentsply rinn stabe - BAI - dental SUPA
Decrease kVp by 15 and double exposure time = 10 mA 60 impules 75 kVp
Patient positioning
To distinguish b/w patient's right and left side

21. What is the latent image
Located on the tooth surface that contacts the adjacent tooth
Invisible image (remains like this until film is processed)
Left molar PA
Filters placed in PID after tubehead production

22. When mounting a FMS - you notice that one film is blank. another film is dark - the teeth look strange - and it is difficult to determine What film it is. What do you think happened?
6 ft
Original - undeflected - useful beam
Reg. replenishment and changing out expired solutiong with fresh chemicals at reg. intervals; monitor strength of chemicals on a daily basis
Dark film is from over exposure and improper packet placement for strange looking teeth and not being able to determine What film is

23. How should x-ray film be stored
Original packaging -area sheilded from radiation -50-70 degrees F
Highest of the 2 ridges - about the level of the cervical 3rd - behind the 2nd and 3rd molars
Enamel - dentin - and bone
Positioning the arches too far foward

24. In the darkroom - you unwrap a film and place a coin on top of the film for several minutes. when you process the film - you notice a slight - well-defined white circle on the film. What does this mean?
Failed safelight test - suggesting that the safelight conditions in the darkroom are fogging the film
X-rays hit phosphor screen creating florescent light that exposes the film
Beam is perpendicular to the imaginary line that bisects the angle formed by the long axis and the film
Labial

25. What causes elongation
Dark film is from over exposure and improper packet placement for strange looking teeth and not being able to determine What film is
Insufficient vertical angulation
Premature contact with developer
Original packaging -area sheilded from radiation -50-70 degrees F

26. How does kVp affect patient exposure
Short-term dose
Higher kVp = low exposure
Copper stem - tungsten target - radiator
Nerve - brain - muscle

27. How are indirect exposure films exposed
X-rays hit phosphor screen creating florescent light that exposes the film
7 1/2 or 15 watt
Roentgen
6 ft

28. What Size film is used to take a BW on a 3 yr. old
Dark film is from over exposure and improper packet placement for strange looking teeth and not being able to determine What film is
#0
Mandibular occlusal
Labial

29. which dose of radiation is more biologically damaging
Insufficient or improper washing
Chronic low-level exposures/long term dose; causing cancer - cataracts - low birth weight - genetic mutations - and embryological defects
2.75 inches
Labial

30. What is the purpose of taking radiographs of an edentulous patient
detect pathological lesions -establish position of mental foramen -establish position of mand canal -determine quality & quantity of alveolar bone present
50 mSv (5rem)
Genetic cells
Located on the tooth surface that contacts the adjacent tooth

31. With What type film are intensifying screens used?
Occlusal
Patient positioned too far foward in the focal trough
extraoral film
invisible -travel in straight lines -no mass/weight -travel and speed of light -no charge -interact w/ matter causing ionization -can penetrate opaque tissues and structures -can effect photographic film emulsion -can effect biologic tissue

32. What type film is faster - intraoral or extraoral
Doesn't matter
Extra oral
Rectangular collimations
Occlucal

33. when should radiographs be taken on a pregnant patient
Only when necessary to help the dentist diagnose and treat oral diseases; elective xrays should be postponed until after delivery
Mandibular occlusal
Original - undeflected - useful beam
Patient positioning

34. desired thickness of lead apron
B/c of its stability to produce a large volume of radiographs in a short amount of time
Copper stem - radiator and air space
.25 mm
Premature contact with developer

35. when processing - two films overlap in the developer - but not in the fixer. How would the films appear
Left side
Patient movement
Patient's dental arches; maxilla and mandile
Clear/blue in the area of overlap b/c fixer will not remove all crystals

36. What must be done to xray fixer priod to disposal
Remove silver
Excessive vertical angulation
7 1/2 or 15 watt
B/c of its stability to produce a large volume of radiographs in a short amount of time

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

38. What is the purpose of the lead foil?
locate retained roots -locate unerrupted or impacted teeth -evaluate for diseases and lesions -locate foreign bodies -reveal presence of salivary stones (sialothiths) -aid in evaluating fractures -size and shape of tori -aid in examining patients wit
Maintain acidity & alkalinity & prevent oxidation -
Absorb scatter radiation and prevent fogging
Soft cloth - non abrasive cleaner

39. What factors would decrease edge sharpness and increase magnification
8-16 inches
#2
Premature contact w/ developing chemicals - Drops of developer or fixer that splash onto the work area and came in contact with the film.
Far object-image receptor distance

40. How are x-rays formed in the tubehead
Time b/w exposure and 1st clinically observable symptoms
Only when necessary to help the dentist diagnose and treat oral diseases; elective xrays should be postponed until after delivery
Negative
turn on machine -adjust settings -press exposure button -filament heats up/thermoionic emmision -electron cloud is formed -electrons flow from cathode to anode -electrons strike target -energy is converted into x-rays and heat

41. When looking at radiographs that were taken several years ago - you notice a brownish stain which makes interpretation difficult. What caused this?
Premature contact with developer
Sv & Rem
Max arch ala-tragus parallel to floor - mand arch
Insufficient or improper washing

42. What Size film is 1 1/16 x 2 1/8
68 degrees F
No. 3
Stop taking xrays and evaluate all equipment and techniques to ensure safety
Part that was fixed but not developed would be clear

43. What causes missing crowns
Excessive vertical angulation
Cosmic - naturally occuring radiation from earth - radiation for radioactive materials
Maintain acidity & alkalinity & prevent oxidation -
Didn't push button completely

44. What type of safelight filter is acceptable
Absorb scatter radiation and prevent fogging
Blue tinted polyester acetate
GBX - 2
Parallel

45. A patient complains of pain in the upper molar region. What radiographic exposure should be made?
underexposure-underdevelopment -depleted developer solution -excessive fixation (takes all crystals off)
Image the entire dentition - surrounding alveolar bone - sinuses - and the TMJ - examine large area of face and jaws - locate impacted teeth - retain root tips - evaluate trauma - lesions - and diseases - and assess growth and development
Periapical
Dentsply rinn stabe - BAI - dental SUPA

46. What 2 unites are used to measure absorption
Overexposure -overdevelopment -developer is too strong -not enough fixation -exposure to white light -improper safelighting
Green light sensitive film (Kodak T-Mat)
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
Gray & Rad

47. Size film used for occlusals on adults
#4
Top of film delineated by a straight line then dark
Sv & Rem
Direct - directly obtaining a digital image by exposing intraoral sensor to x-rays to provide an image that can be viewed on a computer - indirect - photostimuable phosphor plate sensor technology - obtaining a digital image in which an exposed phosp

48. You notice on a PANO that the ant. teeth appear narrow and out of focus. What caused this
Increase the area of radiation exposure
Patient positioned too far foward in the focal trough
Absorb scatter radiation and prevent fogging
Mand. foramen

49. According to the principles of shadow casting - preferred object-film distance
Beam is perpendicular to the imaginary line that bisects the angle formed by the long axis and the film
As close as possible
Overexposure -overdevelopment -developer is too strong -not enough fixation -exposure to white light -improper safelighting
Premature contact with developer

50. Size film used for PA's on small children
#0
Scatter/secondary radition
Image the entire dentition - surrounding alveolar bone - sinuses - and the TMJ - examine large area of face and jaws - locate impacted teeth - retain root tips - evaluate trauma - lesions - and diseases - and assess growth and development
Cosmic - naturally occuring radiation from earth - radiation for radioactive materials