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 causes conecut
Not centered on sensor
Far object-image receptor distance
Size of crystals - thickness of emulsion - radiosensitive dyes
bisecting was used b/c of the distortion of the elongated root - the roots appeared long b/c the vertical angulation was inadequate

2. you notice that a radiograph taken several months ago is brown and spotted. What happened
Insufficient or improper washing
Cancer - cateracts - embryologic defects - genetic mutations - low birth weight
Mandibular occlusal
No. 2

3. What must be done to xray fixer priod to disposal
Far object-image receptor distance
Excessive VA w/ PID positioned too steep enough away from zero degrees
Release of electrons when a material such as tungsten is heated to incandescence - electrons are boiled off from the cathode filament in the x-ray tube when electric current is passed through it
Remove silver

4. when viewing a duplicated radiograph - you notice that the duplicate is too dark. What should you do to duplicating time to lighten the film
Before fixing
Removes the unexposed silver halide crystals
Old or contaminated processing solutions -exposure to chemical fumes -faulty safelight -scatter radiation
Increase the exposure time

5. when manually processing dental film - you notice the temp. has gotten warmer as the day progressed. How should the developing time be changed?
7 1/2 or 15 watt
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
Dentin - enamel - bone
Higher temp. increases film fog - so radiographer should consult a time-temp. development chart to adjust developing time appropriately; developing time will decrease

6. In which area of the tooth is interproximal caries often seen
Thyroid collar - lead and lead-equivalent sprons are availaable with or without an attached thyroid collar
Located on the tooth surface that contacts the adjacent tooth
Duplicate - which will go to the insurance comp.; office keeps best copy
decrease mA & time

7. What is the purpose of taking radiographs of an edentulous patient
Density
detect pathological lesions -establish position of mental foramen -establish position of mand canal -determine quality & quantity of alveolar bone present
Mental foramen - mental ridge - mand canal
Clinical exam

8. What is the most important step in panoramic radiography
#2
Perpendicular to the tooth and film
Patient positioning
Increased focal spot size - decrease source-object distance - & increased object-film distance

9. What is the primary beam
5 mSv or .5 REM
Original - undeflected - useful beam
Old or contaminated processing solutions -exposure to chemical fumes -faulty safelight -scatter radiation
X-rays that have been deflected from an object and have changed paths

10. 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
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
20 min
4 feet

11. What is the maximum size of the x-ray beam at the patients face
Excessive vertical angulation
2.75 inches
Sterilize film holder devices or discard disposable image receptor holding devices
Method should be compensated for bisecting or paralleling

12. after processing exposed dental film - you notice dark spots on the film. What caused this
Density
Premature contact with developer
take 14 radiographs -omit the BW -paralleling should be technique of choice -panoramic might be better than FMS
Cut exposure time by 1/3

13. when viewing a PANO - you notice that the right TMJ is magnified - bu the left TMJ is normal. What caused this error
Only when necessary to help the dentist diagnose and treat oral diseases; elective xrays should be postponed until after delivery
Patient positioned too far to the left
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
BW

14. your dentist recommends that a patient have xrays taken - bu the patient refuses. What should be done

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183

15. Size film used for occlusals on adults
#4
50 mSv (5rem)
Cancer - cateracts - embryologic defects - genetic mutations - low birth weight
Step-wedge or test film

16. What is the bremsstrahlung radiation
Evidence based selection criteria
Step-wedge or test film
On the back side of the tori
Aka general radiation; stopping or slowing of the electrons of the cathode stream as they collide with the nuclei of the target atoms

17. you notice that the xrays you process are becoming successively lighter than the quality control film you compare it to. What should you do
Patient positioned too far foward in the focal trough
Original packaging -area sheilded from radiation -50-70 degrees F
Check the processing chemical - particularly the developer
Reg. replenishment and changing out expired solutiong with fresh chemicals at reg. intervals; monitor strength of chemicals on a daily basis

18. What is the most likely cause of a film with very poor definition
Cathode - filament - focusing cup
Patient movement
Oral piercings - earings - glasses - necklaces - facial piercings - hair pins - hearing aids - dentures - and retainers
Excessive VA w/ PID positioned too steep enough away from zero degrees

19. What causes missing crowns
No. 1
Nasal fossa - max sinus
Aka general radiation; stopping or slowing of the electrons of the cathode stream as they collide with the nuclei of the target atoms
Excessive vertical angulation

20. Mand premolar anatomy
Mental foramen - mental ridge - mand canal
Ionization
Filament
Eyewear - mask - and gown

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

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183

22. What anatomical structures appear radiopaque on a dental radiograph
extraoral film
Sterilize film holder devices or discard disposable image receptor holding devices
Enamel - dentin - and bone
#2

23. What factors affect the sharpness of the radiographic image
Dark film is from over exposure and improper packet placement for strange looking teeth and not being able to determine What film is
No. 0
Large blank space is due to reversed image error or chemical contamination - missing apices is due to inadequate VA
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

24. What is the major diff. b/w particulate and electromagnetic radiation
No. 2
As far as practical
particulate radiation: made of protons - neutrons - electrons and alpha and beta particles; has mass -electromagnetic radiation: made of photons; no mass
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

25. which projection is used to view sinuses
Genetic cells
Increased focal spot size - decrease source-object distance - & increased object-film distance
PANO
Insufficient vertical angulation

26. What Size film is 1 1/16 x 2 1/8
Patient's name - date - and other pertinent info
No. 3
Gently agitating the hanger up and down a few times
Insufficient or improper washing

27. What is the purpose of replenishing the developer solution
Maintain acidity & alkalinity & prevent oxidation -
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
No. 3
Filtration and collimation

28. What size bulb is used in safelight
Rectangular collimation
No. 2
Excessive vertical angulation
7 1/2 or 15 watt

29. When taking a radiograph - you pull the end of the PID away from the patients face about 6 inches. How will this affect the radiographic image and patient exposure
Lighter image - patient exposed to larger beam which will increase exposure
1/3-1/2
Rectangular collimations
Reg. replenishment and changing out expired solutiong with fresh chemicals at reg. intervals; monitor strength of chemicals on a daily basis

30. What is the main source of radiation exposure to the operator
Scatter/secondary radition
#0
Enamel - dentin - and bone
Lighter image - patient exposed to larger beam which will increase exposure

31. What looking at a PANO What causes a big smile
Reduces the exposed silver halide crystals to black metallic silver
Patient movement
Chin down
decrease mA & time

32. What is the base of dental film composed of?
68 degrees F
Chronic low-level exposures/long term dose; causing cancer - cataracts - low birth weight - genetic mutations - and embryological defects
Blue tinted polyester acetate
1/4 as intense

33. What must a patient remove before taking a PANO
Oral piercings - earings - glasses - necklaces - facial piercings - hair pins - hearing aids - dentures - and retainers
BW
The emulsion side of the film is placed against the orginal radiograph with the nonemulsion side up
Evidence based selection criteria

34. What are the short term effects of radiation exposure
1/6th of a second
Erythema - vomitting - nausea - hemorrage - diarrhea - hair loss
Higher temp. increases film fog - so radiographer should consult a time-temp. development chart to adjust developing time appropriately; developing time will decrease
15 impulses

35. How can you differentiate the zygoma from the max sinus in a max posterior PA
Max arch ala-tragus parallel to floor - mand arch
Reg. replenishment and changing out expired solutiong with fresh chemicals at reg. intervals; monitor strength of chemicals on a daily basis
Zygoma will be radiopaque - max. sinus will be a large area of radiolucency
Stop taking xrays and evaluate all equipment and techniques to ensure safety

36. What radiographs are used to determine if a foreign object is located facially or lingually
Occlusal
#2
Every 6 mths
Patient positioned too far to the left

37. What is the annual MPD for pregnant dental assistant
#0
KVp
5 mSv or .5 REM
Top of film delineated by a straight line then dark

38. What equation is used to calculate the accumulated MPD
7 1/2 or 15 watt
Scatter/secondary radition
5(n-18)
Erythema - vomitting - nausea - hemorrage - diarrhea - hair loss

39. How does kVp affect patient exposure
Rectangular collimation and fast film speed
Higher kVp = low exposure
20 seconds
Maintain acidity & alkalinity & prevent oxidation -

40. What is thermionic emission
Old or contaminated processing solutions -exposure to chemical fumes -faulty safelight -scatter radiation
Release of electrons when a material such as tungsten is heated to incandescence - electrons are boiled off from the cathode filament in the x-ray tube when electric current is passed through it
Tori
No exposure to x-rays - electrical failure - malfunction of x-ray machine - or processing errors

41. What looking at manually processed films - you notice small black spots on the films. What caused those spots?
Film placed backwards
Dentsply rinn - XCP - XCP-DS - flow dental RAPD
Premature contact w/ developing chemicals - Drops of developer or fixer that splash onto the work area and came in contact with the film.
CCD (direct) - CMOS (direct) - PSP (indirect)

42. when mounting a film the dot is convex - On What side of the mouth would you find #32?
Roentgen
Left side
Excessive vertical angulation
Step-wedge or test film

43. When viewing a periapical radiograph - you notice that the image of the tooth is extremely long and well defined; However the apices are missing. What technique was used to take the radiograph? What caused the roots to appear long?
bisecting was used b/c of the distortion of the elongated root - the roots appeared long b/c the vertical angulation was inadequate
Mand canal - external oblique ridge - beg. of ramus
Reduce size and shape of beam
Genetic cells

44. Max molar anatomy
No. 3
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
Max sinus - zygoma - max tuberosity - coranoid process
Removes the unexposed silver halide crystals

45. How does packet placement differ b/w bisecting and paralleling
bisecting - packet is as close to tooth as possible - but not parallel -parallel - packet is parallel to tooth - further away
Movement caused by the patient - slippage of the image receptor - or vibration of the tube head
Oral piercings - earings - glasses - necklaces - facial piercings - hair pins - hearing aids - dentures - and retainers
Reduce size and shape of beam

46. What is the best method of protecting the thyroid gland from radiation?
Coulombs/kilogram(C/kg) & Roentgen (R)
Produced by internal barriers in tube head (ex: glass and insulating oils)
Thyroid collar - lead and lead-equivalent sprons are availaable with or without an attached thyroid collar
Scatter/secondary radition

47. How would a film appear if submerged totally in the developer but not in the fixer
Patient positioned too far foward in the focal trough
Decrease kVp by 15 and double exposure time = 10 mA 60 impules 75 kVp
Top of film delineated by a straight line then dark
Max. sinus - zygoma

48. How long does the first rinse last
extraoral film
#2
20 seconds
Not as sharp and detailed as the intraoral image

49. How do you determine How often to take radiographs
max molars have 3 roots - mand have 2 roots
Long-term dose
Evidence based selection criteria
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

50. your film badge report sHows that you have received a small amt. of radiation. What should you do
Cut exposure time by 1/3
Dentsply rinn - XCP - XCP-DS - flow dental RAPD
Stop taking xrays and evaluate all equipment and techniques to ensure safety
Not as sharp and detailed as the intraoral image