Radiation Characteristics Flashcards
Mean energy or penetrating ability of the x-ray beam which is controlled by kilovoltage
Quality
Refers to the potential difference between two electrical charges
Voltage
Is the measurement of electrical force that causes electrons to move from the negative cathode to the positive anode
Voltage
What is the measurement of voltage?
Kilovolts (kV)
Unit of measurement used to describe the potential that drives an electrical current through a circuit
Volts
Dental radiography requires the use of how many kV?
65 to 100 kV
Is controlled by the kilovoltage peak adjustment on the x-ray control panel
Kilovoltage
Defined as the maximum or peak voltage
Kilovoltage peak
A beam that contains many different wavelengths of varying intensities that is produced as a result of varying kilovoltages occurring in the tube current
Polychromatic x-ray beam
This regulates the speed and energy of the electrons and determines the penetrating ability of the x-ray beam
Quality and kilovoltage peak
Overall darkness or blackness of a film
Density
When the kilovoltage peak is increased while other exposure factors remain constant, the resultant film exhibits an?
Increased density and appears darker
If kilovoltage is decreased, the resultant film exhibits a?
Decreased density and appears lighter
Refers to how sharply dark and light areas are differentiated or separated on a film
Contrast
What is a film with many black and white areas and a few shades of gray? What causes it?
High contrast film
Low kVp setting
What is a film with many shades of gray instead of black and white? What causes it?
Low contrast film
High kVp setting
What is the range for low kVp setting?
65-70 kVp
What is the range for high kVp setting?
≥90 kVp
Refers to the interval of time during which x-rays are produced
Exposure time
Exposure time is measured in
Impulses
According to the kilovoltage peak rule, when kVp is increased by 15, exposure time should be?
Decreased by one-half
According to the kilovoltage peak rule, when kVp is decreased by 15, exposure time should be?
Doubled
Refers to the numbers of x-rays produced
Amperage
Unit of measure used to describe the number of electrons, or current, flowing through the cathode filament
Ampere
In dental radiography, the use of how many milliampere is required?
7-15 ma
Regulates the temperature of the cathode filament
Milliamperage
Increase in milliamperage increases the overall density of the radiograph and results in?
A darker image
Decrease in milliamperage decreases the overall density of the radiograph and results in?
A lighter image
When milliamperage is increased, exposure time must be?
Decreased
When milliamperage is decreased, exposure time must be?
Increased
The product of the quantity and quality per unit of area per unit of time of exposure
Intensity
Controls the penetrating power of the x-ray beam by controlling the number of electrons produced in the x-ray tube and the number of x-ray produced
Intensity and Milliamperage
The distance from the source of radiation to the patient’s skin
Target-surface distance
The distance from the source of radiation to the tooth
Target-object distance
The distance from the source of radiation to the receptor
Target-receptor distance
According to this law, the intensity of radiation is inversely proportional to the square of the distance from the source of radiation
Inverse Square Law
Are used to remove the low-energy, less penetrating, longer wavelength x-rays
Aluminum filters
Increased the mean penetrating capability of the x-ray beam while reducing the intensity
Aluminum filters
To reduce the intensity of the x-ray beam, aluminum filters are placed in the path of the beam inside the dental x-ray tubehead
Half-value layer
