su14_-_radiology_exam_2_20141210195322 Flashcards
(192 cards)
1
Q
What type of light is used to see each other and read?
A
reflected light
2
Q
What type of light is used to interpret radiographs (film and digital)?
A
transmitted light
3
Q
Incident light (total light from source such as view box or illuminator) is partly: ____, ____ and ____.
A
transmitted, absorbed, and reflected
4
Q
When viewing a radiograph, do you want a white or a black background and surroundings?
A
black
5
Q
What is the most active component of radiographic film?
A
AgBr
6
Q
When exposed to x-rays (or visible light), ____ is ____ which, after processing, is converted to ____.
A
- AgBr- ionized- metallic silver
7
Q
The greater the amount of radiation that reaches the film, the ____ the amount of metallic silver (Ag) forms.
A
greater
8
Q
What is the color of metallic silver (Ag) on a radiograph?
A
black
9
Q
Parts of the film receiving more radiation appear ____ (darker/lighter) while those receiving less radiation appear ____ (darker/lighter).
A
- darker- lighter
10
Q
If we processed an unexposed film, how would it appear?
A
clear because no AgBr was ionized
11
Q
If we processed a film exposed to substantial amount of x-radiation, how would it appear?
A
black
12
Q
Digital receptors have ____ electrons.
A
trapped
13
Q
In digital receptors, the higher the concentration of trapped electrons, the ____ (higher/lower) the density.
A
higher
14
Q
Is radiolucent a darker or lighter section on a radiograph?
A
darker
15
Q
To make a radiolucent part of a radiograph, ____ (more/less) x-rays will reach the image receptor, ____ (more/less) metallic Ag will form or ____ (more/less) trapped electrons, and a ____ (darker/lighter) image will appear.
A
- more- more- more- darker
16
Q
To make a radioopaque part of a radiograph, ____ (more/less) x-rays will reach the image receptor, ____ (more/less) metallic Ag will form or ____ (more/less) trapped electrons, and a ____ (darker/lighter) image will appear.
A
- less- less- less- lighter
17
Q
Radiolucency and -opacity always refer to nature and characteristic of a ____.
A
object (not to be confused with radiographic density which refers to the blackness or darkness of an area of a film)
18
Q
What is the definition of radiographic density (D)?
A
the blackness or darkness of an area of film; deals with the whole radiograph; may have values 0.25, 0.5, 1.0, 1.5, 2.0, 3.0, etc.
19
Q
What is the usable range of radiograph density?
A
0.25-2.5
20
Q
What is the definition of radiographic contrast?
A
refers to the observed differences in adjoining radiographic densities OR difference in densities between light and dark regions on a radiograph
21
Q
What does good radiographic contrast enable us to do?
A
enables us to differentiate one structure from another, if they differ in density, thickness, and/or chemical composition; helps differentiate between normal and carious enamel, normal and abnormal bone, etc.
22
Q
What is the difference between high and low contrast?
A
- high contrast: differences between adjoining radiographic densities are greater- low contrast: differences are smaller
23
Q
High contrast is synonymous with a ____ (short/long) scale contrast or in other words, ____ (more/less) shades of gray.
A
- short scale contrast- less shades of gray
24
Q
Low contrast is synonymous with a ____ (short/long) scale contrast or in other words, ____ (more/less) shades of gray.
A
- long scale contrast- more shades of gray
25
If you are trying to look at an image with a lot of different densities, you want a ____ (higher/lower) contrast because you want ____ (more/less) shades of gray.
- lower- more
26
True or false: Extraoral radiographic examinations constitutes majority of dental imaging.
FALSE. INTRAORAL radiographic examinations constitutes the majority of dental imaging.
27
What are the 3 categories of intraoral radiographs?
- periapical (PA)- bitewing (BW)- occlusal
28
What does a full-mouth series consist of?
14-17 periapical images4 bitewings
29
What are the criteria (4) for quality images?
- adequate diagnostic quality- completely covers the area of interest- least amount of magnification and distortion- optimal density and contrast
30
True or false: You retake a radiograph only if required information is not of diagnostic quality.
true
31
What are the 2 projection techniques that may be used for periapical radiography?
- paralleling- bisecting angle
32
What projection technique is most commonly used when taking periapical radiographs?
paralleling technique because there is less image distortion
33
In a paralleling technique of taking a periapical radiograph, where is the image receptor and where is the central ray directed?
- image receptor is parallel to the long axis of the teeth- central ray directed at right angle to image receptor and teeth
34
In paralleling technique of taking a periapical radiograph, should there be a long or short source-to-object distance? Why?
long (reduces magnification)
35
What color positioning instrument and what size film are used for posterior periapical radiographs?
- gold/yellow positioning instrument- size 2 film
36
What color positioning instrument and what size film are used for anterior periapical radiographs?
- blue positioning instrument- size 1 film
37
How is the tube head angulated for a periapical radiograph?
- adjust the x-ray tube head making sure the central ray is at right angle to the image receptor- make the tube head flush with the positioning instrument (if using positioning instrument with no external ring, keep the end of the cone within 2 cm of patient's skin)- position the tube head downward for maxillary PAs (positive vertical angulation) or upward for mandibular PAs (negative vertical angulation)- be careful of incorrect horizontal angulation of beam (overlapping of interproximal surfaces of crowns)
38
What is the difference between positive and negative vertical angulation?
- positive vertical angulation: used for maxillary PAs; positioning the tube head downward- negative vertical angulation: used for mandibular PAs; positioning the tube head upward
39
What rule is the bisecting angle technique of taking periapical radiographs based on?
Cieszynski's rule of isometry (2 triangles are equal if they share one complete side and have 2 equal angles)
40
In the bisecting angle technique of taking periapical radiographs, where is the image receptor placed? Where is the central ray directed?
- image receptor placed as close as possible to lingual surfaces of teeth and palate or lingual surface of mandible; the receptor and teeth meet at an angle- an imaginary bisector line bisects the angle between the image receptor and teeth; central ray of x-ray beam is directed at a right angle to the imaginary bisector
41
For a bisecting angle technique of taking a periapical radiograph, if all four conditions are met, the image is theoretically ____.
of the same size as the object (no distortion)
42
Performing a radiographic exam involves:- ____ procedure- no ____ contact normally- ____ protocol is observed- ____ protocol if needed
- non-invasive procedure- no blood contact normally- barrier protocol is observed- disinfection protocol if needed
43
For barrier protocol, plastic bags are used for covering what 3 things?
- chair headrest- x-ray tube head- exposure switch
44
For barrier protocol, what needs to be worn by the operator?
- gloves- face mask- green colored coat
45
For barrier protocol, what needs to be worn by the patient?
- protective apron- thyroid shield
46
What should be wiped with a caviwipe in a radiographic exam room?
all surfaces not protected with a barrier that came in contact with gloved hands or any other contaminants such as saliva
47
What are the steps (8) of starting a radiographic exam?
- have the radiographic procedure approved by the supervising faculty member on the clinic floor- make patient sit upright comfortably and explain the procedure- drape patient with protective apron and thyroid shield- wash your hands, wear gloves and face mask- examine the oral cavity- place the film in the positioning instrument and place in the oral cavity- position the PID and go behind the barrier- press the exposure button
48
For periapical radiographs of maxillary anterior teeth, what color positioning instrument is used? What size film? What position should the film be in (vertical/horizontal) and where should it be placed?
- blue-colored positioning instrument- size 1 film- vertical film position- place films as far back (toward throat) as possible
49
For periapical radiographs of maxillary posterior teeth, what color positioning instrument is used? What size film? What position should the film be in (vertical/horizontal) and where should it be placed?
- yellow-colored positioning instrument- size 2 film- horizontal position- place film in the midline (away from teeth being imaged)
50
For periapical radiographs of mandibular anterior teeth, what color positioning instrument is used? What size film? What position should the film be in (vertical/horizontal) and where should it be placed?
- blue-colored positioning instrument- size 1 film- vertical position- place the film on the floor of the mouth (not on the tongue!) and push the tongue back as far as possible
51
For periapical radiographs of mandibular posterior teeth, what color positioning instrument is used? What size film? What position should the film be in (vertical/horizontal) and where should it be placed?
- yellow-colored positioning instrument- size 2 film- horizontal position- place film on floor of mouth (not on tongue!) between the tongue and alveolar ridge
52
What is bitewing radiography also called? What is imaged in a bitewing radiograph?
- interproximal radiography- crowns and alveolar crests of maxillary and mandibular teeth (all on same radiograph)
53
What is bitewing radiography used to detect?
- interproximal caries- marginal periodontal bone loss- interproximal calculus
54
For posterior molar bitewing, where is the line on the positioning instrument placed?
between the 1st and 2nd molars
55
What are the 7 special circumstances that make taking a bitewing radiograph difficult?
- gag reflex- infection- trauma- mentally-disabled patient- physically-disabled patient- pregnancy- edentulous patient
56
What are the 3 parts of the Buccal Object Rule?
1. image of the area of interest is acquired in a standard way2. a second image is acquired with a changed horizontal angulation of the PID3. object towards the buccal seems to move in the opposite direction of the PID
57
What are some other names for the Buccal Object Rule?
image shift principle or SLOB rule
58
For the Buccal Object Rule, the object that "moves" in the same direction is ____ (buccal/lingual); the object that "moves" in the opposite direction is ____ (buccal/lingual).
- lingual- buccalHint: remember "Same Lingual Opposite Buccal" (SLOB)
59
What is the definition of image sharpness?
how well-defined is a boundary between two areas of differing radiodensities (ex. how well you can discern between dentin and enamel)
60
What is the definition of image resolution?
how well an image is able to reveal very small objects that are very close together
61
What are the desired characteristics of image formation?
- minimum magnification- minimum distortion- minimum superimposition- maximum detail
62
True or false: Magnification is present even if film and object are parallel.
true
63
Magnification depends on what 3 factors?
- object-film distance (OFD)- source-object distance (SOD)- source-film distance (SFD)
64
What are 4 synonyms for "source of radiation"?
- source- target- focal spot- anode
65
If there is a constant source-object distance, increased object-film distance (film moves away from the object), then magnification ____ (increases/decreases).
increases
66
If there is a constant source-film distance, increased object-film distance (object moves towards the source), then magnification ____ (increases/decreases)
increases
67
Object-film distance should be as ____ (small/large) as possible (affects image sharpness).
small
68
More magnification = ____ (more/less) sharp
less
69
If there is constant object-film distance, decreased source-film distance, then magnification ____ (increases/decreases).
INCREASES
70
If there is constant object-film distance, increased source-film distance, then magnification ____ (increases/decreases).
decreases
71
True or false: Source-film distance should be short rather than long.
FALSE. SFD should be long rather than short (also affects sharpness)
72
What is the length of a typical short cone and a typical long cone?
- typical short cone: 8" or less- typical long cone: 12" or 16"
73
What length of cone is most common? What is recommended?
- most common is 8"- recommended is longer than 8"
74
What is the definition of distortion?
variation seen in image from the true shape or proportions of the object (unequal magnification in an image)
75
What are the 2 types of distortion?
- distortion of size- distortion of shape
76
Distortion seen in an image is due to ____.
disproportionate (non-uniform) magnification; some parts of the image are more magnified than the others
77
Minimum distortion occurs when the object and sensor are ____ and the central ray is ____ to both the object and the film.
- parallel- perpendicular
78
If the relationship between the object and film is ____, more acute distortion occurs.
angular (not parallel)
79
Using the bisecting angle technique, if the central ray is directed at a right angle to the object, ____ results. If the central ray is directed at a right angle to the sensor, ____ results.
- elongation- foreshortening
80
For proper application of the bisecting angle principle, the length of the image and object ____ (are/are not) equal and distortion ____ (is/is not) present.
- are- is
81
In improper application of the bisecting angle principle, ____ is too great and there is image ____ and image shift ____.
- vertical angulation- foreshortening- shift occlusally or incisally
82
In improper application of the bisecting angle principle, ____ is too small and there is image ____ and image shift ____.
- vertical angle- elongation- apically (opposite to source of radiation)
83
In proper application of the parallel principle, there is ____ and minimal ____.
- magnification- distortion
84
In improper application of the parallel principle in which the vertical angle is too great, there is no ____ and image shift ____.
- foreshortening- occlusally; may project off of the receptor
85
In improper application of the parallel principle in which the vertical angle is too small, there is no additional ____ and image shift ____.
- elongation- apically (toward root apices); may project off of the receptor
86
The bisecting angle technique is performed by first visualizing the bisector of the angle. Then, you direct the invisible ____ of the x-ray beam at a ____ degree angle to the imaginary bisector. If a mistake is made, it will result in ____ or ____.
- central ray- 90- foreshortening- elongation
87
The paralleling technique is performed by placing the sensor ____ (parallel/perpendicular) to teeth. The central ray is directed at a ____ degree angle to the sensor. If a mistake is made, there is no ____ or ____, but there is ____.
- parallel- 90- foreshortening- elongation- magnification
88
What type of cone is mandatory for the paralleling technique? Why?
long cone because you need an increased source-film distance (SFD)
89
True or false: A long cone is necessary for the bisecting angle technique.
FALSE. A long cone is not necessary for bisecting angle technique, but there is no disadvantage when a long cone is used.
90
Radiographic detail involves what 3 factors?
- radiographic contrast- resolution- radiographic definition
91
What is the definition of radiographic definition? What is the term "definition" equal to?
- refers to the recorded sharpness of boundaries of structures- definition and sharpness are synonymous; lack of definition and unsharpness are synonymous
92
What are the variables involved in radiographic definition?
- size of the source (focal spot)- OFD, SFD, SOD- movement (of patient or sensor)- nature of the image receptor
93
When determining radiographic definition, a source can either be a ____ source or a ____ source. It can give yield an image due to ____ (actual image) or ____ (periphery of image).
- point source- area source- umbra- penumbra
94
The size of the source and the definition are ____ (directly/inversely) related.
inversely
95
The size of the source and the unsharpness are ____ (directly/inversely) related.
directly
96
All factors that ____ (increase/decrease) magnification will ____ (increase/decrease) definition.
- increase- decrease
97
True or false: It is very significant if the source of radiation moves while taking a radiograph.
FALSE. Movement of the source of radiation is not very significant.
98
True or false: It is very significant if the patient and/or image receptor moves while taking a radiograph.
true
99
What is movement of the source of radiation also called? Movement of the patient and/or image receptor?
- geometric unsharpness- motion unsharpness
100
For vertical angulation of maxillary teeth, 0 degrees VA is when the central ray is ____. Positive VA is when the source of radiation is ____.
- parallel to occlusal plane- superior to the point of entry of central ray (PID is pointing downward)
101
When there is an increased or positive vertical angulation of a maxillary PID, what may result in terms of the image?
image shifts down (incisal/occlusal edges may be projected off the receptor)
102
If there is a decreased or negative vertical angulation of the PID when taking a maxillary radiograph, what may happen to the image?
image shifts up (apices may project off the receptor)
103
For what type of radiograph (maxillary/mandibular) do you want a positive angulation? Negative angulation?
- maxillary teeth- mandibular teeth
104
Negative vertical angulation occurs when the source of radiation is ____.
inferior to the point of entry of the central ray; the PID is pointing upward
105
When taking a mandibular radiograph, increasing the vertical angulation causes what change in the image?
causes the image to shift up (incisal/occlusal edges may be projected off of the receptor)
106
When taking a mandibular radiograph, decreasing the vertical angulation causes what change in the image?
causes the image to shift down (apices may be projected off of the receptor)
107
True or false: The vertical angulation for all maxillary periapicals, bitewings and occlusal radiographs is always positive; there is never an exception.
true
108
True or false: The vertical angulation for maxillary periapicals is lesser than for bitewings.
FALSE. The vertical angulation for maxillary periapicals is GREATER than for bitewings.
109
Which vertical angulation is greater: maxillary anterior periapicals or posterior periapicals?
maxillary anterior periapicals
110
What is a 0 degree horizontal angulation? 90 degree? 180 degree?
- 0 degree: central ray is parallel to sagittal plane and directed anteroposteriorly- 90 degree: central ray is perpendicular to the sagittal plane- 180 degree: central ray is parallel to the sagittal plane and directed posteroanteriorly
111
Improper horizontal angulation causes ____.
interproximal overlapping
112
Increasing horizontal angulation causes images to shift ____ and results in ____.
- anteriorly- overlapping
113
Decreasing horizontal angulation causes images to shift ____ and results in ____.
- posteriorly- overlapping
114
As we successively expose incisor, canine, premolar, and molar periapicals, in general, horizontal angulation ____.
increases (source of radiation moves posteriorly)
115
In periapical radiography, horizontal angulation varies from ____ degrees (incisor periapical) to approximately ____ degrees (molar periapical).
0 degrees90 degrees
116
What is the definition of digitization?
to represent a particular object (radiograph, photo, diagram, etc.) in form of numerical digits (ex. combination of zeros and ones)
117
What are the 8 types of digital images used in dentistry?
- intraoral- panoramic- cephalometric- skull and sinus- tomography- CT/CBCT, MRI, PET, nucelar medicine- intraoral photography/videography- microscopy (surgical and histological)
118
What is the definition of a digital image?
a radiographic image represented in a digital format (combination of zeros and ones)
119
What are the 2 types of digital imaging?
- direct digital imaging- indirect digital imaging
120
What is the difference between direct and indirect digital imaging?
- direct: radiographic images obtained by x-ray exposure of solid-state image detectors- indirect: radiographic images obtained by exposing a digital image detector and scanning or digital photo capture of film radiographs
121
True or false: There is not an intermediate step of "reading" or "scanning" in direct digital imaging.
true
122
What are the 2 types of direct digital imaging?
- charge-coupled device (CCD)- complementary metal oxide semiconductor (CMOS)
123
What are the 3 types of indirect digital imaging?
- photostimulable storage phosphor plate (PSP)- scanning a film- taking a digital photo of a film
124
What is a charge-coupled device (CCD)? How does it acquire an image?
- image detector that is made of high-grade pure silicone that contains an array of pixels (picture elements) that are coupled to each other- image acquisition is a process of transferring accumulated light or x-ray photons from one electronic well to another on a read-out device; then that analog image is transferred to the Intermediate Electronics Unit which makes it a digital image
125
What is the difference between a processed and unprocessed digital image?
an unprocessed image has each pixel assigned a different value of zeros and ones so the image looks very pixelated (boxy)
126
What are the advantages (4) of charge-coupled devices (CCDs)?
- instant availability of images- better image quality compared to PSP- durable- consistent image quality (because they are enclosed in a hard plastic case)
127
What are the disadvantages (4) of charge-coupled devices (CCDs)?
- expensive- bulky- wire attachment- smaller active area compared to an equivalent size film (because there is a lot more hardware taking up space in the digital receptor)
128
What is a complementary metal oxide semiconductor (CMOS)? How does it compare to a CCD?
- silicone-based semiconductor that is widely used in video camera detectors and central processing chips of computers- principle similar to CCD, but simpler circuit design; the photon/electron conversion takes place right at the pixel (unlike CCD)
129
What are the advantages (5) of a complementary metal oxide semiconductor (CMOS)?
- instant availability of image- durable- consistent image quality- less expensive than CCD- slightly more rugged than CCD
130
What are the disadvantages (4) of a complementary metal oxide semiconductor (CMOS)?
- expensive compared to PSP- bulky; wireless is even bulkier- wire attachment- smaller active area compared to an equivalent sized film
131
What type of clinic is the best place to use a Photostimulable Storage Phosphorplate (PSP)?
pediatric clinic
132
What are the 2 components of a photostimulable storage phosphorplate (PSP)?
- supporting base- outer coating of radiosensitive phosphor material
133
In photostimulable storage phosphorplates (PSPs), the phosphor is "____-doped" ____ which is similar to ____ phosphors, but the difference is that PSP ____.
- europium-doped- barium fluorohalide (BrFBr:Eu)- intensifying screen- PSP traps a significant number of electrons in its phosphor which is later read by a laser beam
134
In PSPs, the phosphor layer absorbs ____ which moves ____ to ____.
- x-ray photons (energy)- valence electron- conduction band
135
In PSPs, the number of electrons stored is proportional to ____ to produce a ____.
- x-ray photons- latent image
136
PSPs are scanned by a laser beam of ____ nm (____ spectrum).
- 633 nm- red
137
Describe how a photostimulable storage phosphorplates (PSP) takes an image.
- phosphor layer absorbs x-ray photons (energy)- energy moves valence electron to the conduction band (the number of electrons stored is proportional to x-ray photons)- scanned by a laser beam of 633 nm (red spectrum)- trapped electrons return to valence band and emit 300-500 nm light (green spectrum)- transported to photomultiplier tube- light energy is converted to electrical energy (ADC) which is stored and displayed as a digital image
138
What are the advantages (4) of PSPs?
- wider latitude (forgiving in choice of kVp and mAs)- available in all standard sizes- well tolerated by patients- economically priced
139
What are the disadvantages (5) of PSPs?
- prone to scratches (short lifespan)- read-out should be done ASAP (no more than 6-8 hours)- require processing- a semi-dark room is required- require exposure to bright light for erasing previous image before reuse
140
What are the 4 detector characteristics of digital detectors?
- contrast resolution- spatial resolution- detector latitude- detector sensitivity
141
What is the definition of contrast resolution? What bit depth do current digital detectors capture?
- ability to distinguish different densities in radiographic image- capture data at 8-, 10-, 12, or 16-bit depth
142
How many densities/gray levels are there in current digital detectors? In conventional computer monitors? Human visual system? Dental operatory?
- digital detectors: 256-65536 gray levels- computer monitors: 8 bits; 242 gray levels- human visual system: 60 gray levels- dental operatory: less than 30 gray levels
143
What is the definition of spatial resolution?
ability to identify two objects placed very close to each other
144
What is the spatial resolution of D-speed films? Of digital images? Of normal (untrained) eyes?
- D-speed film: >20 line pair/mm- digital images: >7-24 line pair/mm- normal eye: 4-6 line pair/mm
145
What is the definition of detector latitude?
the ability of an image detector to capture a range of x-ray exposures of tissue densities ranging from (ex.) gingiva to enamel; at the same times, subtle differences in density should be visually apparent
146
What is the useful range of detector latitude?
0.5-2.5
147
What is the definition of detector sensitivity?
ability of detector to respond to a smaller amount of radiation; in intraoral films, known as "speed" (D-, E-, or F-speed); there are no such standards for dental digital detectors
148
For PSP systems, approximately the same dose is required as a ____ film (thus, they have the same detector sensitivity).
F-speed
149
In hi-resolution CCD and CMOS systems, approximately how much of a dose is required for optimal exposure of an F-speed film?
half of a dose
150
A monitor consists of what 3 components?
- display device (cathode ray tube (CRT), thin film transistor (TFT), organic light emitting diode (OLED))- circuitry- enclosure
151
What are the 3 types of display devices?
- cathode ray tube (CRT): 256 gray values- thin film transistor (TFT): ultra hi-resolution- organic light emitting diode (OLED): higher contrast and better viewing angle than LCD
152
A hard copy of a radiograph can be on what two mediums?
paper or film
153
What is the definition of image processing? What characteristics of the image does it affect?
- an operation that acts to improve, restore, analyze, or change a digital image- brightness, contrast, gamma value, sharpening and smoothing filters, color, and digital subtraction
154
Why is image processing beneficial? How can it be detrimental?
- improves diagnostic accuracy if used judiciously- may improve the diagnosis of one disease while obscuring another; fraud
155
When looking at caries in a radiographic image, do you want high or low contrast? When looking at bone?
- caries: high contrast- bone: low contrast
156
What was image analysis designed to do? What two things does it do?
- designed to extract diagnostically important information from an image- measurement and diagnosis
157
In image analysis, what are the tools (3) used for measurement?
- digital rulers- densitometers- trabecular bone pattern (osteopenia and osteoporosis)
158
What are the advantages (6) of digital imaging?
- instant images- lower radiation dose- consistent quality- high signal/noise ratio (SNR)- image manipulation- digital subtraction radiography
159
What are the disadvantages (5) of digital imaging?
- relatively lower resolution than film- quality depends on monitor and printer- print quality is often not optimal- higher initial cost- unwanted manipulation of images
160
For CCD, CMOS, PSP, and film, rank the spatial resolution.
film > CCD = CMOS > PSP
161
For CCD, CMOS, PSP, and film, rank the exposure latitude.
PSP >> CCD = CMOS > film
162
For CCD, CMOS, PSP, and film, rank the receptor dimensions.
film = PSP < CCD = CMOS
163
For CCD, CMOS, PSP, and film, rank the time required for image acquisition.
CCD = CMOS <<< PSP = film
164
For CCD, CMOS, PSP, and film, rank the image quality.
subjective; film is considered to be a gold standard
165
For CCD, CMOS, and PSP, rank the image adjustment and processing.
CCD = CMOS = PSP
166
For digital and film radiography, rank the cost.
there is a high initial cost of digital systems
167
For digital and film radiography, rank the reliability.
digital systems are more susceptible to problems
168
For CCD, CMOS, PSP, and film, rank the image storage and retrieval.
back-up is critical for digital systems
169
For CCD, CMOS, PSP, and film, rank the transmission of images.
CCD = CMOS = PSP >>> film
170
What is DICOM?
"digital imaging and communication in medicine"; recognized standard for communication of images and related information
171
True or false: Use of DICOM is voluntary, but international.
true
172
True or false: DICOM is only used for radiographs and cannot be used for photography.
FALSE. DICOM is applicable to all imaging including radiographs and photographs
173
What are the 3 reasons for the use of DICOM? Describe each.
- efficiency: integration of different modalities in one dental office- portability: simplify exchange of images between dental and medical offices when patients move or require specialist care- integrity: attributes uniquely identify the patient, procedure, procedure date, and protect image integrity
174
Radiographic examination shall only be prescribed on the basis of what 3 selection criteria?
- history- clinical examination- laboratory findings (in some cases)
175
True or false: There is a routine time-based formula for obtaining radiographs.
FALSE. There is no routine time-based formula for obtaining radiographs because there are individual circumstances for each patient. Judgements for the care of a specific patient, including radiographic examination, can only be made by using training and expertise.
176
In what year was the selection criteria for radiographic examinations developed? When was it most recently updated?
- 1987- updated in 2004 and then again in 2012
177
In deciding the selection criteria for a radiographic examination, in what 2 groups are patients placed?
symptomatic and asymptomatic
178
What radiological exams are recommended for a symptomatic patient?
- use of individual periapical radiographs to examine a specific site or tooth because of specific signs or symptoms or historical findings- use of other radiographic techniques (panoramic, occlusal, head films, CBCT, etc.) should be considered where appropriate (ex. jaw pathosis, trauma, TMJ disorders, implants, paranasal sinuses, etc.)
179
True or false: There are separate guidelines for radiographic exams for symptomatic child, adolescent, and adult.
FALSE. There are separate guidelines for radiographic exams for an ASYMPTOMATIC child, adolescent, and adult.
180
For an asymptomatic child who is a new patient, what is the guidelines for radiographic exam of primary dentition? For transitional dentition?
- bitewings if clinical examination is not possible or clinical signs of disease- individual periapicals and/or occlusals and bitewings OR panoramic and bitewings
181
For an asymptomatic child who is a recall patient, what is the guidelines for a radiographic exam if they have clinical caries or are at high caries risk? If they have no clinical caries or are not at high caries risk?
- bitewings every 6 months until no evidence of caries- bitewings every 12-24 month intervals
182
For an asymptomatic child who is a recall patient, what is the guidelines for a radiographic exam if they have periodontal disease or a history of periodontal disease? If they are undergoing a growth and development assessment?
- selected periapicals and/or bitewings of clinically positive sites- selected periapicals, panoramic, and occlusal (as indicated)
183
For an asymptomatic adolescent who is a new patient, what are the guidelines for a radiographic exam?
- posterior bitewings and selected periapicals- full-mouth series when patient presents with clinical evidence of generalized diseaseAND/OR- full-mouth series when patient presents with history of extensive dental treatment
184
For an asymptomatic adolescent who is a recall patient, what is the guidelines for a radiographic exam if they have clinical caries or are at high caries risk? If they have no clinical caries or are not at high caries risk?
- bitewings every 6-12 months until no evidence of caries- posterior bitewings at 18-36 month intervals
185
For an asymptomatic adolescent who is a recall patient, what is the guidelines for a radiographic exam if they have periodontal disease or a history of periodontal disease? If they are undergoing a growth and development assessment?
- selected periapicals and/or bitewings (vertical preferred) of clinically positive sites- perapicals or panoramic to assess developing 3rd molars
186
For an asymptomatic adult who is a new patient, what are the guidelines for a radiographic exam?
- posterior bitweings and selected periapicals- full-mouth series when patient presents with clinical evidence of generalized disease- full-mouth series when patient presents with history of extensive dental treatment
187
For an asymptomatic adult who is a recall patient, what are the guidelines for a radiographic exam if they have clinical caries or are at high caries risk? If they have no clinical caries or are not at high caries
- bitewings every 12-18 months or until no carious lesions are evident- posterior bitewings every 24-36 months
188
For an asymptomatic adult who is a recall patient, what are the guidelines for a radiographic exam if they have periodontal disease or a history of periodontal disease? If they are undergoing a growth and development assessment?
- selected periapicals and/or bitewings (vertical preferred) of clinically positive sites- usually not indicated
189
For an edentulous adult who is a new patient, what are the guidelines for a radiographic exam?
- panoramic radiograph- full-mouth series (usually not required)
190
For an edentulous adult who is a recall patient, what are the guidelines for a radiographic exam?
- no recall radiographic examinations required- selected periapicals or panoramics when disease is suspected
191
What are the special considerations for radiographic exams for patients who are pregnant?
- an appropriate radiographic examination for symptomatic patients- use radiation protection apron (thyroid and body)- if patient is asymptomatic, postpone if possible- fetal exposure is only 1 mGy for a full-mouth series
192
What are the special considerations for radiographic exams for patients undergoing radiation therapy?
- dental exposure is insignificant compared to therapeutic doses (up to 50 Gy)- an appropriate radiographic examination is recommended- average skin dose from dental radiography is 3 mGy- patients at a high risk for "radiation caries," radiation exam is usually beneficial
