Exam 2 Flashcards
(104 cards)
1
Q
What are the 3 types of x-ray film?
A
Intraoral
Extraoral
Duplicate film
2
Q
What is a recording medium?
A
Film
3
Q
What are the components of the intraoral film packaging?
A
- Outer package wrapping
- Paper film wrapper
- Lead foil sheet
- X-ray film
4
Q
What are the two sides of the outer package wrapping of the intraoral film?
A
Tube side
Label side
5
Q
What side of the intraoral film must face teeth?
A
Tube side (white side)
6
Q
What side of the intraoral film must face the tongue?
A
Label side
7
Q
What is a soft vinyl or paper wrapper that seals intraoral film packet?
A
Outer package wrapping
8
Q
What is the protective sheet that covers film and shields light of intraoral film?
A
Paper film wrapper
9
Q
Single sheet placed behind film wrapped in protective paper for the intraoral film
A
Lead foil sheet
10
Q
What shields intraoral film from backscatter radiation?
A
Lead foil sheet
11
Q
What are the components of the X-ray film?
A
Double-emulsion
One or two film packet
Identification dot
12
Q
What are the components of film composition?
A
- Film base
- Adhesive order
- Film emulsion
- Protective layer
13
Q
What consists of gelatin and silver halide crystals?
A
Film emulsion
14
Q
What gives sensitivity to x-radiation?
A
Film emulsion
15
Q
Flexible polyester plastic (0.2mm thick) with a slight blue tint
A
Film base
16
Q
- Chemical sensitive to radiation and light
- Absorb radiation during exposure
A
Halide crystals
17
Q
What are the two types of halide crystals?
A
Silver bromide
Silver Iodine
18
Q
- Suspends and disperses microscopic silver halide crystals
- Absorbs solution and allows chemicals to react with silver halide crystals
A
Gelatin
19
Q
Energy is stored in silver halide crystals when film exposed to radiation
A
Latent image
20
Q
Almost no radiation received
A
Behind amalgam
21
Q
Most radiation received
A
Behind airspace
22
Q
How many watts does a safelight have to be in a darkroom?
A
15 watts or less
23
Q
What are the steps of manual film processing?
A
- development
- rinsing
- fixing
- washing
- drying
24
Q
What step is removed from automatic film processing?
A
First rinse step
25
What are the ingredients in developer solution?
- Developing agent
- Preservative
- Accelerator
- Restrainer
26
What are the two developing agents?
Hydroquinone
Elon
27
What is the preservative in developer solution? Function?
Sodium sulfite
- prevents oxidation
28
What is the accelerator in developer solution? Function?
Sodium carbonate
- Activates developing agent
29
What is the restrainer in developer solution? Function?
Potassium bromide
- Prevents development of unexposed halide crystals
30
What are the fixer solution ingredients?
- Fixing agent
- Preservative
- Hardening agent
- Acidifier
31
What is the fixing agent in fixing solution? Function?
Sodium thiosulfate OR Ammonium Thiosulfate
- Removes unexposed or undeveloped silver halide crystals from emulsion
32
What is the preservative in fixer solution? Function?
Sodium sulfite
- Prevents deterioration of fixing agent
33
What is the hardening agent of fixer solution? Function?
Potassium alum
- Shrinks and hardens emulsion
34
What is the acidifier in fixer solution? Function?
Acetic acid or sulfuric acid
- Neutralizes pH of alkaline developer
35
What are the only speeds used in intraoral radiography?
D and F
36
Shows bony and soft tissue areas of facial profile
Cephalometric film
37
What is the majority of extraoral films?
Screen film
38
What is not recommended for use in dental radiography?
Nonscreen film
39
What is the extraoral film equipment?
- Intensifying screens
- Cassette
40
What transfers x-ray energy into invisible light to expose screen film for extraoral film?
Intensifying screens
41
What is used for patient referrals, insurance claims, teaching aids, etc?
Duplicating film
42
How is film stored?
- Cool and dry
- Temps between 50 and 70 F
- Away from radiation
- First in, first out
43
Radiographic image produced by film
Analog image
44
Filmless imaging system
Digital imaging
45
Image composed of pixels and stored on computer
Digital image
46
Picture element, unit of measure for contained digital information, digital equivalent to silver halide crystal in film
Pixel
47
Receptor used to capture intraoral/extraoral image
Sensor
48
What protects the sensor?
Front casing
49
What converts x-ray beam to visible light in the sensor?
Scintillator screen
50
What transmits light to sensor?
Fiber optic face plate
51
What captures light and charges pixel?
CMOS imaging chip
52
What reads charged pixels and transmits to computer in the sensor?
Sensor electronics
53
What protects and prevents backscatter for the sensor?
Back casing
54
What are the 3 types of digital sensors?
- Charged-couple device
- Complementary metal oxide semiconductor
- complementary metal oxide semiconductor-active pixel sensor
55
What digital sensor has a silicon chip and electrical circuit?
Charged-couple device
56
What digital sensor has smaller pixel size and lower power requirements?
Complementary metal oxide semiconductor
57
What digital sensor improves signal output and has a computer connection via USB?
Complementary metal oxide semiconductor-active pixel sensor
58
What is the difference between CCD and CMOS?
The way pixels are read
59
How big is a pixel?
2mm
60
Obtaining digital images by exposing an intraoral sensor to x-radiation
Direct imaging
61
Obtaining digital images by scanning a sensor after exposure to x-radiation and converting that data into digital form
Indirect imaging
62
What do you need for direct digital imaging?
-Intaoral x-ray unit
-Sensor
-Computer with imaging software
63
What do you need for indirect digital imaging?
- Intraoral x-ray unit
- PSP plate
- Scanner
- Computer with imaging software
64
Many images collected to give one view
Panoramic imaging
65
What can be seen on a panoramic image?
Maxilla
Mandible
Oral and facial structures
66
What are the uses for a panoramic image?
o Evaluate
dentition/impacted teeth
o Evaluating development
o Disease detection
o Evaluate trauma
67
Why would we NOT use a panoramic image?
Diagnosing the following:
- Decay/caries
- Periodontal disease
- Periapical lesions
68
Why would we use extraoral bitewing imaging?
Discomfort/difficulty with intraoral exposures
Children, patients with special needs
Gag reflex
Large tori
Small mouth
69
Allows us to photograph one section of the body while burying others
Tomography
70
Pivot point/axis around which a receptor and x-ray tube head rotate
Rotation center
71
3-D curved zone in which structures are clearly demonstrated
Focal trough
72
o Structures lie between the receptor and moving rotation center
o Appears in correct anatomic location with varying degrees of sharpness and distortion
Real image
73
o Anatomic structure is located behind moving rotation center
o Penetrated twice by x-ray bean
o Same proportions as real image
o Located in same location on opposite side of receptor – mirror image
Double image
74
What are structures at the midline?
Epiglottis
Hyoid bone
Cervical spine
75
o Anatomic structure located outside focal plane and close to x-ray source
o Resembles true image
o Found on opposite side of receptor
Ghost image
76
What structures are located laterally or centrally?
Ramus
Jewelry
Hard palate
77
What does PAN equipment consist of?
Tubehead
Head positioner
Exposure control
Collimator
78
What does film PAN equipment consist of?
- CCD, CMOS, PSP plate, or film
- Screen film
- Intensifying screens
- Cassette
79
What steps are taken to prep the patient for a PAN image?
o Remove all artifacts
o Lead apron
o Patient bites on groove, standing tall
o Midsagittal plane
o Frankfort plane
o Tongue to roof of mouth, lips together
o Stand still
80
bottom of eye, top of ear canal
Frankfort plane
81
What needs to be parallel to the floor for a PAN image?
Frankfort plane
82
How do you know if adequate contrast is seen on a PAN image?
DEJ seen
83
What are some common PAN imaging patient errors?
-Artifacts
-Thyroid collar
-Chin too high/low
-Twisted/turned neck
-Too far forward/back
-Slumping
-Tongue/lip placement
84
What are some PAN film errors?
-No bite block
-Damaged screen/patient tilted
-Light leak
-Fog
-Improper loading
-Static electricity
-Movement
85
What are the advantages of PAN imaging?
o Field size
o Simplicity
o Patient cooperation
o Minimal exposure
86
What are the disadvantages of PAN imaging?
o Image quality
o Focal trough limitations
o Distortion
o Equipment cost
87
What does extraoral imaging evaluate?
Larger areas on skull/jaw
Development
Impacted teeth
Disease
Trauma
TMJ
88
What is the receptor holder and head positioner for extraoral imaging?
Cephalostat (craniostat)
89
What does lateral jaw imaging examine?
posterior region of mandible
90
What can be seen in the body of the mandible for lateral jaw imaging?
Impacted teeth
Fractures
Lesions
91
What can be seen in the ramus of the mandible for lateral jaw imaging?
Third molars
Larger lesions
Fractures
92
What does lateral cephalometric projection evaluate?
* Facial growth and development
* Trauma, disease, abnormalities
93
What does Posteroanterior projection evaluate?
* Facial growth and development
* Trauma, disease, abnormalities
94
What does Submentovertex projection evaluate?
* Position of condyles
* Base of skull
* Zygomatic arch fractures
* Sphenoid
* Ethmoid
* Sinuses
* Lateral wall of maxillary sinus
95
What does waters projection evaluate?
Maxillary sinus
96
What does reverse town projection evaluate?
Fractures of condylar neck and ramus
97
What does Temporomandibular joint imaging evaluate?
* Temporal bone
* Mandible
* Glenoid fossa
* Articular eminence
* Condyle
* Articular disk
98
* 3D viewing of oral-maxillofacial structures
* Cone-shaped x-ray beam
* Field of view
Cone-beam computed tomography (CBCT)
99
What are 3C pixels?
Voxels
100
How long does it take for a CBCT machine to work?
7-30 seconds
101
What is the number 1 use of CBCT?
Implant placement
102
What are the advantages of CBCT?
o Lower radiation dose
o Brief scanning time
o Anatomically accurate images
o Save/transport images
103
What are the disadvantages of CBCT?
o Patient movement and artifacts
o Size of FOV
o Cost of equipment
o Training
o Lack of training in interpretation
104
What is expose control based on?
Type of x-ray
Patient size
