Chapter 38:
Foundatins of
Radiography,
Radiographic
Equipment and
Radiation Safety
(solved)
Acute Radiation Exposure - answer When a
large dose of radiation is absorbed in a short
period such as in a nuclear accident
Chronic Radiation Exposure - answer When
small amounts of radiation are absorbed
repeatedly over a long period. The effects of
,chronic exposure may not be observed until
years after the originial exposure.
ALARA Concept - answer As Low As
Reasonably Possible for radiation exposure
Three factors that influence sharpness of an
image - answer 1. focal spot size (smaller =
sharper) 2. Film composition (fast = less
sharp) 3. Movement.
Five procedures that protect the patient from
radiation - answer 1. Lead apron 2. Fast
speed flim 3. Film holding devises 4.
Exposure Factor - limit amount of exposure 5.
Proper Technique - films that are
nondiagnostic must be retaken, so dont make
mistakes.
Radiolucent structures - answer appear dark
on a radiograph because radiation can easily
pass through. Examples: air spaces,
abscesses, tooth decay, and dental pulp
,Radiopaque structures - answer radiation
does not easily pass through, Examples are:
metal restorations, tooth enamel, and dense
areas of bone.
Components of a dental x-ray machine -
answer 1. Tubehead 2. X-ray Tube 3. Position
Indicator Device 4. Extension Arm 5. Control
Panel
radiation - answer Forms of waves of energy
emission through space or material
Photons - answer a tiny bundle of pure
energy that has no weight or mass
Ionization - answer the process of removing
electrons and forming ions
Density - answer The overall darkness and
blackness of a radiograph, can be affected by
distance from x-ray tube to patient,
developing time/temp and body size of
patient
, Geometric characteristics that affect the
quality of a radiograph - answer Sharpness,
magnification, and distortion
Critical organs affected by radiation - answer
Lens of the eye - cataracts 2. Bone Marrow -
Leukemia 3. Salivary Gland - Cancer 4.
Thyroid Gland - Cancer 5. Skin - Cancer 6.
Gonads - Genetic Abnormalities.
Types of radiation - answer Primary radiation,
secondary radiation, and scatter radiation
Penumbra - answer The blurred or indistinct
area that surrounds an image
Distortion - answer Change in the size of an
image on a radiograph caused by incorrect
vertical angulation
Magnification - answer Refers to the
proportionate enlargement of a radiographic
image
Foundatins of
Radiography,
Radiographic
Equipment and
Radiation Safety
(solved)
Acute Radiation Exposure - answer When a
large dose of radiation is absorbed in a short
period such as in a nuclear accident
Chronic Radiation Exposure - answer When
small amounts of radiation are absorbed
repeatedly over a long period. The effects of
,chronic exposure may not be observed until
years after the originial exposure.
ALARA Concept - answer As Low As
Reasonably Possible for radiation exposure
Three factors that influence sharpness of an
image - answer 1. focal spot size (smaller =
sharper) 2. Film composition (fast = less
sharp) 3. Movement.
Five procedures that protect the patient from
radiation - answer 1. Lead apron 2. Fast
speed flim 3. Film holding devises 4.
Exposure Factor - limit amount of exposure 5.
Proper Technique - films that are
nondiagnostic must be retaken, so dont make
mistakes.
Radiolucent structures - answer appear dark
on a radiograph because radiation can easily
pass through. Examples: air spaces,
abscesses, tooth decay, and dental pulp
,Radiopaque structures - answer radiation
does not easily pass through, Examples are:
metal restorations, tooth enamel, and dense
areas of bone.
Components of a dental x-ray machine -
answer 1. Tubehead 2. X-ray Tube 3. Position
Indicator Device 4. Extension Arm 5. Control
Panel
radiation - answer Forms of waves of energy
emission through space or material
Photons - answer a tiny bundle of pure
energy that has no weight or mass
Ionization - answer the process of removing
electrons and forming ions
Density - answer The overall darkness and
blackness of a radiograph, can be affected by
distance from x-ray tube to patient,
developing time/temp and body size of
patient
, Geometric characteristics that affect the
quality of a radiograph - answer Sharpness,
magnification, and distortion
Critical organs affected by radiation - answer
Lens of the eye - cataracts 2. Bone Marrow -
Leukemia 3. Salivary Gland - Cancer 4.
Thyroid Gland - Cancer 5. Skin - Cancer 6.
Gonads - Genetic Abnormalities.
Types of radiation - answer Primary radiation,
secondary radiation, and scatter radiation
Penumbra - answer The blurred or indistinct
area that surrounds an image
Distortion - answer Change in the size of an
image on a radiograph caused by incorrect
vertical angulation
Magnification - answer Refers to the
proportionate enlargement of a radiographic
image
