Review Chapters 1-4

Question 1

What are the radiation characteristics

Answer 1

X-ray beam quality, quantity, and intensity

Question 2

Define quality

Answer 2

The mean energy or penetrating ability of the X-ray beam

Question 3

What controls the quality and why?

Answer 3

KVP. Because the kvp controls the energy and wavelength of the x-ray beam

Question 4

What is voltage and how is it measured?

Answer 4

Voltage is the measurement of electrical force that causes electrons to move from the negative cathode to the positive anode. Measured in KV

Question 5

What regulates the speed and energy of the electrons?

Answer 5

Voltage, or kilovoltage KVP, KV

Question 6

What is density?

Answer 6

Overall darkness or blackness of an image

Question 7

What would make a darker image?

Answer 7

Raising the KVP or MA

Question 8

What does contrast refer too?

Answer 8

How sharply dark and light areas are differentiated or separated on an image

Question 9

If an image has high contrast will it have many shades of grey?

Answer 9

No it will have more dark areas

Question 10

When would you want a high contrast image specifically?

Answer 10

For Bitewings

Question 11

If you lower the KVP what happens to you contrast of your image?

Answer 11

Your contrast increases

Question 12

What does exposure time refer to?

Answer 12

The interval of time during which X-rays are produced

Question 13

How is the exposure time measured?

Answer 13

In impulses

Question 14

I impulse occurs every?

Answer 14

1/60 of a second

Therefore 60 impulses occur in 1 second

Question 15

If the KVP is decreased the exposure time?

Answer 15

Exposure time should be increased

Because if you lower the KVP you will have less penetrating beam power so you will need for X-ray time on the matter you are trying to capture

Question 16

If KVP increased then exposure time?

Answer 16

Exposure time increases

Question 17

What does exposure time effect?

Answer 17

Contrast and density which ultimately effects the overall quality

Question 18

If someone had a hard time staying still during film exposure what settings would you change?

Answer 18

The mA could be increased while the exposure time is decreased

Question 19

What is mA usually preset too?

Answer 19

7 mA

Question 20

mA increases the heating of what part in the tube head?

Answer 20

Tungsten filament at the negative pole cathode

Question 21

What does mA do?

Answer 21

Increases quantity of photons (X-rays) by increasing the number of electrons produced in the cathode

Question 22

Does a high mA increase the temperature?

Answer 22

Yes

Question 23

Increase in mA has what effect on density?

Answer 23

Increase in mA increases overall density results in a darker image

Question 24

Decrease in mA has what effect on density?

Answer 24

Decreased overall density

Resulting in a lighter image

Question 25

What should you do with exposure time for small children?

Answer 25

Decrease it

Question 26

What is intensity?

Answer 26

Product of quantity and quality per unit of area per unit of time of exposure

Question 27

What are the several distances you must consider when exposing a dental radiograph?

Answer 27

Target surface distance Target object distance Target receptor distance Object film distance

Question 28

What is the relationship between distance and intensity of radiation called?

Answer 28

Inverse square law

Question 29

If the distance of the X-ray tube increases what happens to intensity?

Answer 29

The intensity decreases Think of a flashlight on a wall

Question 30

If the PID length is changed from 8 to 16" how does this increase in source-to-receptor distance affect the intensity of the beam?

Answer 30

The beam will be 1/4 as intense

Question 31

What is the purpose of the aluminium filter?

Answer 31

Reduce intensity and remove the low Energy X-rays from the beam

Question 32

What is HVL?

Answer 32

Half value layer. | Refers to the thickness of aluminum when placed in the path of the X-ray beam reduces the intensity by 1/2

Question 33

Electromagnetic radiation

Answer 33

Travels at the speed of light Travels as both particle and a wave Possesses different measurable energies: frequencies and wavelengths

Question 34

Wavelength

Answer 34

Measured by the crests (peaks) of one wave and crest of the next Determines entertainment and penetrating power of radiation

Question 35

What is frequency

Answer 35

Number of wavelengths that pass a given point in a certain amount of time High frequency=short wavelength Short frequency=long wavelength

Question 36

What is x-radiation

Answer 36

High energy, ionizing electromagnetic radiation

Question 37

X-ray

Answer 37

Posses particles of waves and particles Photons Travels at the speed of light Posses short wavelengths and high frequency X-rays travel in straight lines and can be deflected or scattered Cause ionization in tissue

Question 38

Where are X-rays produced?

Answer 38

Tube head

Question 39

What is in the tubehead?

Answer 39

Cathode terminal anode terminal

Question 40

What is inside the tube head envelope?

Answer 40

Lead and the tubehead is insulated by surrounding oil

Question 41

Where is the molybdenum and what is its purpose?

Answer 41

It is in the cathode and embed's the tungsten filament. It is responsible for directing the electrons to the tungsten target of the anode

Question 42

Incandescence

Answer 42

The cool becomes white with the generation of heat

Question 43

What is the anode made of

Answer 43

Copper rod to dissipate heat and tungsten target

Question 44

What is the collimator?

Answer 44

Lead plate with a central hole that fits directly over the opening of the metal housing where the X-rays exit

Question 45

What restricts the size of the X-ray beam

Answer 45

Collimator

Question 46

What is exposure time affected by

Answer 46

Radio graphic technique Type of X-ray film Tissues being radiographed Target film distance

Question 47

An X-ray machine is capable of generating radiation?

Answer 47

1/60 of a second

Question 48

Does alternating current flow in continuous direction?

Answer 48

No

Question 49

What are transformers?

Answer 49

Devices used to increase or decrease the voltage in an electrical circuit

Question 50

What do transformers do?

Answer 50

Transformers alter the voltage of the incoming electrical current and then route the electrical energy to the X-ray tube

Question 51

What are the 3 transformers used?

Answer 51

Step down Step up Autotransformers

Question 52

General radiation

Answer 52

Consists of many different energies and wavelengths | Occurs when an electron hits the nucleus or comes close to the nucleus of the tungsten atom

Question 53

Primary radiation

Answer 53

X-ray beam that is produced at the target of the anode and exits the tube head Referred to as primary or useful beam

Question 54

Secondary radiation

Answer 54

X-radiation that is created when primary beam interacts with matter ex: tissues of head Less penetrating than primary radiation

Question 55

Scatter radiation

Answer 55

Form of secondary

Question 56

Compton scatter

Answer 56

Ejected electron is known as Compton or recoil electron possessing a negative charge Compton accounts for 62% of the scatter that occurs in radiography

Question 57

Who first discovered X-rays

Answer 57

Dr.wilhelm Conrad roentgen

Question 58

Who introduced bisecting technique

Answer 58

Weston price

Question 59

Who introduced bite wing tech

Answer 59

Howard Riley raper

Question 60

Who introduced paralleling technique

Answer 60

C.Edmund Kelly