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. How does resolutiong and detial of a panoramic radiograph compare with that of PA's and BW's
Ionization
Not as sharp and detailed as the intraoral image
Zygoma will be radiopaque - max. sinus will be a large area of radiolucency
Quantum of energy

2. What is the emulsion composed of?
detect pathological lesions -establish position of mental foramen -establish position of mand canal -determine quality & quantity of alveolar bone present
Overdevelopment -temp. too high -time too long -developer concentration too high -inadequate fixation -accidental exposure to light -improper safelighting
Gelatin and silver halide crystals
Lateral cephalometric

3. How far should the operator stand from the source of radiation
6 ft
max molars have 3 roots - mand have 2 roots
Max. sinus - zygoma
PANO

4. How can exposure to the operator be reduced
1/6th of a second
Move farther from the radiation
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
Increased focal spot size - decrease source-object distance - & increased object-film distance

5. Explain PSP
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
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
Genial tubercles - lingual foramen
Rectangular collimation and fast film speed

6. What 3 types of cells are most radiosensitive
Patient positioned too far foward in the focal trough
Only when necessary to help the dentist diagnose and treat oral diseases; elective xrays should be postponed until after delivery
GBX - 2
WBC - RBC - immature reproductive cells

7. What NC agency is resposible for monitoring dental x-ray equipment
Dentsply rinn stabe - BAI - dental SUPA
Size of crystals - thickness of emulsion - radiosensitive dyes
5 min
DEHNR

8. Mand central anatomy
Short
No exposure to x-rays - electrical failure - malfunction of x-ray machine - or processing errors
Genial tubercles - lingual foramen
Nerve - brain - muscle

9. What is the optimum processing temp.
68 degrees F
Occlusal
Movement caused by the patient - slippage of the image receptor - or vibration of the tube head
Patient movement

10. How are stabe film holders sterilized b/w uses
#3
Sterilize film holder devices or discard disposable image receptor holding devices
Thyroid collar - lead and lead-equivalent sprons are availaable with or without an attached thyroid collar
Genetic cells

11. What are the long term effects of radiation exposure
Reg. replenishment and changing out expired solutiong with fresh chemicals at reg. intervals; monitor strength of chemicals on a daily basis
Aka general radiation; stopping or slowing of the electrons of the cathode stream as they collide with the nuclei of the target atoms
Occlucal
Cancer - cateracts - embryologic defects - genetic mutations - low birth weight

12. What is the primary beam
#0
bisecting was used b/c of the distortion of the elongated root - the roots appeared long b/c the vertical angulation was inadequate
15 impulses
Original - undeflected - useful beam

13. What is the purpose of the embossed dot

14. How can you differentiate the zygoma from the max sinus in a max posterior PA
Mand occlusal
Zygoma will be radiopaque - max. sinus will be a large area of radiolucency
Roentgen
Higher kVp = low exposure

15. your film badge report sHows that you have received a small amt. of radiation. What should you do
Stop taking xrays and evaluate all equipment and techniques to ensure safety
Every 4 weeks
Rectangular collimation and fast film speed
Excessive VA w/ PID positioned too steep enough away from zero degrees

16. when taking a PANO radiograph - the patient is placed too far into the machine. How will the radiograph appear
Patient positioned too far foward in the focal trough
As low as reasonably achievable
Lead
All of the ant. teeth will appear blurred and narrowed in width

17. in which pericapical projection will the mental ridge be visible
bisecting was used b/c of the distortion of the elongated root - the roots appeared long b/c the vertical angulation was inadequate
Mandibular lateral/central
Dentsply rinn - XCP - XCP-DS - flow dental RAPD
No exposure to x-rays - electrical failure - malfunction of x-ray machine - or processing errors

18. What are common sources of background radiation
detect pathological lesions -establish position of mental foramen -establish position of mand canal -determine quality & quantity of alveolar bone present
Cracking of the emulsion caused by excessive temp diff. b/w any darkroom solutions
Perpendicular to the tooth and film
Cosmic - naturally occuring radiation from earth - radiation for radioactive materials

19. when processing - two films overlap in the developer - but not in the fixer. How would the films appear
X-ray and heat
On the back side of the tori
Step-wedge or test film
Clear/blue in the area of overlap b/c fixer will not remove all crystals

20. What is the proper patient position for BW's?
Ala-tragus line is parallel to the floor
Occlusal
nasal septum - ant. nasal spine - nasal fossa - median palatine suture - incisive foramen
Invisible image (remains like this until film is processed)

21. Size film used for BW on adults when only one film is taken on each side
No. 1
20 seconds
#3
20 min

22. What type of film are calcium tungstate screens paired with
Blue light sensitive films
Mental foramen - mental ridge - mand canal
KVp
Patient positioned too far to the left

23. What type of angulation is used when taking radiographs of the mand. arch
Premature contact with developer
Clear/blue in the area of overlap b/c fixer will not remove all crystals
Left side
Negative

24. What are filters made out of...
Produced by internal barriers in tube head (ex: glass and insulating oils)
Only when necessary to help the dentist diagnose and treat oral diseases; elective xrays should be postponed until after delivery
Mand. foramen
Aluminum

25. What are three types of image receptors used in digital radiography
CCD (direct) - CMOS (direct) - PSP (indirect)
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
GBX - 2
Blue tinted polyester acetate

26. What is formed when high speed electrons strike the target
underexposure-underdevelopment -depleted developer solution -excessive fixation (takes all crystals off)
Move farther from the radiation
Perpendicular to the tooth and film
X-ray and heat

27. What type PID significantly reduces exposure to the patient
Highest of the 2 ridges - about the level of the cervical 3rd - behind the 2nd and 3rd molars
Rectangular collimations
Move farther from the radiation
1.5 mm

28. What happens in the fixer
Cracking of the emulsion caused by excessive temp diff. b/w any darkroom solutions
Removes the unexposed silver halide crystals
2.5 mm
max molars have 3 roots - mand have 2 roots

29. What is secondary radiation
1/4 as intense
Erythema - vomitting - nausea - hemorrage - diarrhea - hair loss
Rapidly producing cells are more sensitive to radiation
X-rays that have gone thru an object and are now a newer weaker beam

30. According to principles of shadow casting - How should the central beam be directed
Negative
Perpendicular to the tooth and film
Patient positioned too far foward in the focal trough
Evidence based selection criteria

31. 3 film holding devices used for bisecting
Dentsply rinn stabe - BAI - dental SUPA
50 mSv (5rem)
nasal septum - ant. nasal spine - nasal fossa - median palatine suture - incisive foramen
Premature contact w/ developing chemicals - Drops of developer or fixer that splash onto the work area and came in contact with the film.

32. With What type film are intensifying screens used?
extraoral film
Increase the area of radiation exposure
#1 or #2 - placed so the edge of the receptor lines up behind the distal of the canine before the eruption of the permanent 2nd molar; - after the eruption of the perm. 2nd molar - 2 posterior PA's should be taken per quadrant
2.75 inches

33. What 3 types of cells are most radioresistant
Insufficient vertical angulation
Nerve - brain - muscle
Filters placed in PID after tubehead production
Not as sharp and detailed as the intraoral image

34. What would cause the radiographic image to be blurred
Movement caused by the patient - slippage of the image receptor - or vibration of the tube head
Patient positioning
1/4 as intense
No exposure - or fixer before developer

35. you notice that a radiograph taken several months ago is brown and spotted. What happened
Stop taking xrays and evaluate all equipment and techniques to ensure safety
Only when necessary to help the dentist diagnose and treat oral diseases; elective xrays should be postponed until after delivery
Insufficient or improper washing
Take FMS on all new patients; recall adults with no sig. med. history only require BW and PA - if indicated

36. How long does the first rinse last
25
Absorb scatter radiation and prevent fogging
#1 or #2 - placed so the edge of the receptor lines up behind the distal of the canine before the eruption of the permanent 2nd molar; - after the eruption of the perm. 2nd molar - 2 posterior PA's should be taken per quadrant
20 seconds

37. when mounting a film the dot is convex - On What side of the mouth would you find #32?
Left side
#0
Increase the area of radiation exposure
No. 4

38. What is the bremsstrahlung radiation
Aka general radiation; stopping or slowing of the electrons of the cathode stream as they collide with the nuclei of the target atoms
Vertical BW
#0
8-16 inches

39. Max molar anatomy
Max sinus - zygoma - max tuberosity - coranoid process
#4
50 mSv or 5 REM
5(n-18)

40. What is the annual MPD for pregnant dental assistant
5 mSv or .5 REM
Occlucal
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
GBX - 2

41. Film submerged totally in fixer but not in developer
Part that was fixed but not developed would be clear
Aluminum
Erythema - vomitting - nausea - hemorrage - diarrhea - hair loss
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

42. total filtration required of x-ray machines that operate above 70 kVp
2.5 mm
Enamel - dentin - and bone
2.75 inch
6 ft

43. What 2 unites are used to measure biologic effect and dose equivalent
Dentin - enamel - bone
Overdevelopment -temp. too high -time too long -developer concentration too high -inadequate fixation -accidental exposure to light -improper safelighting
Lighter image - patient exposed to larger beam which will increase exposure
Sv & Rem

44. What is the major use of cross sectional occlusal radiograph
Periapical examination - paralleling technique
Old or contaminated processing solutions -exposure to chemical fumes -faulty safelight -scatter radiation
extraoral film
Provides more info. about the location of tori - impacted and malpositioned teeth and the calcification of soft tissues

45. Size film used for PA's on small children
Soft cloth - non abrasive cleaner
Gray & Rad
#0
Decrease kVp by 15 and double exposure time = 10 mA 60 impules 75 kVp

46. if the source-object distance is cut from 16 to 8 - What must be changed to compensate
Check the processing chemical - particularly the developer
Paralleling; meets more principles of shadow casting
Patient's name - date - and other pertinent info
Method should be compensated for bisecting or paralleling

47. Difference b/w direct and indirect exposure sensor?
Clear/blue in the area of overlap b/c fixer will not remove all crystals
Blue tinted polyester acetate
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
DEHNR

48. What is a large dose of radiation given over a short period of time
1/5 exposure time for edentulous
5 mSv or .5 REM
Short-term dose
20 seconds

49. When interpreting radiographs - you notice a radiopaque extension or spur off the proximal surface of #30. What do you think this is?
5 min
68 degrees F
The mental ridge
Central ray

50. What part of the x-ray machine is responsible for providing the electrons
8-16 inches
nasal septum - ant. nasal spine - nasal fossa - median palatine suture - incisive foramen
Filament
Occlusal