TCDHA Rad theory midterm
Study online at https://quizlet.com/_ehfkkf
1. Define X radiation a high-energy, ionizing electromagnetic radiation produced by the colli-
sion of a beam of electrons with a metal target in xray tube
2. Describe Ionization - atom loses or gains electron, becomes ion
- ejected electron = negative
- remaining atom = positive
- photoelectric effect or compton scatter
3. Primary radiation xray beam produced at target of anode, exits tubehead. primary or "use-
ful" beam
4. Compton scatter evidence of ionization
xray photon collides with outer shell electron, gives up energy to eject
electron from orbit. photon loses energy and continues in different direc-
tions at lower energy. new, weaker photos interacts until all energy gone.
ejected electron + Compton, or recoil and has negative charge
- 62% of radiation
5. Coherent scatter unmodified scatter
low energy photon interacts with outer shell electron. no change in atom
and no ionization.
xray photon scattered but no loss of energy.
8% of radiation
6. Electromagnetic radi- mandmade or natural. no mass, weight or charge. travels at speed of light
ation in both a particle and a wave.
2 measurable energies are frequency and wavelength.
7. what does xray tube- where xrays are produced. sealed glass bulb with lead, all air pumped out
head consist of to create a vacuum. immersed in oil bath to insulate and dispense heat.
, TCDHA Rad theory midterm
Study online at https://quizlet.com/_ehfkkf
Cathode and Anode.
8. what does the filter of aluminum, 1.5-2.5mm thick. Filters out long wavelengths with poor pen-
xray tube do etrating power.
9. what is collimation? limits the radiation dose to the patient by limiting the amount of tissue
that is exposed
10. what does collimator Restricts the size and shape of the x-ray beam to 7cm or 2.75 inches
do
11. Maximum Accumulat- occupationally exposed workers must not exceed MAD. MAD determined
ed Dose (MAD) by age.
MAD = (N-18) x 5 rem/year
MAD = (N-18) x 0.05 Sv/year
N=age, min age 18 to work with rad
12. what is max permissi- max dose a body is permitted to receive in a specific amount of time with
ble dose? what are the little to no injury.
measurements? sv = unit of ionizing radiation
Rem = unit of radiation dosage
5-0 rem/year (0.05msv) for workers
0.1 rem(0.001msv) non workers or pregnant workers
13. 5 rules to the parallel- Film placement - cover prescribed area
ing technique Film Position: parallel to axis, toward middle of oral cavity
Vertical Angulation: central ray directed perpendicular to film
Horizontal Angulation: Central ray directed through contacts
Film Exposure: xray bean centered on film so all areas exposed
14. All size receptors - Size 0: primary posterior: placed horizontally
horizontally or vert Size 1: Mixed dentition: anterior permanent placed vertically, posterior
placed? pedo placed horizontally
, TCDHA Rad theory midterm
Study online at https://quizlet.com/_ehfkkf
Size 2: Perm dentition: Posterior placed horizontally, some perio cases
placed vertically
Size 3: Perm dentition: Posterior placed horizontally, long and narrow, all
premolars and molars captured.
15. Rules to BW Film covers RX'd area
Film positioned parallel to crowns upper and lower
Film stabilized when client occludes
Central ray of beam at +10 degrees
Central ray directed through contacts
Xray beam centered on fil to ensure all areas exposed
16. what is vertical angu- Positive for max, negative for mand. Measured in degrees on outside of
lation? Correct and in- tubehead.
correct? - PID positioned "above" occlusal plane and ray directed "downward" the
VA is POSITIVE
- PID positioned "below" occlusal plane and ray directed "upward" the VA
is NEGATIVE
Incorrect = distortion
17. What is the date xrays November 1895 by Dr. Wilhelm Conrad Roentgen
were discovered? By
whom?
18. what is free radical for- primary means by which x radiation causes cell damage.
mation? occurs when xray photon ionizes water
water ionization = hydrogen + hydroxyl free radicals
19. what is Dose Re- response and damage of tissues with the dose or amount of radiation
sponse Curve? received. no safe amount of rad, even low amounts.
20.
Study online at https://quizlet.com/_ehfkkf
1. Define X radiation a high-energy, ionizing electromagnetic radiation produced by the colli-
sion of a beam of electrons with a metal target in xray tube
2. Describe Ionization - atom loses or gains electron, becomes ion
- ejected electron = negative
- remaining atom = positive
- photoelectric effect or compton scatter
3. Primary radiation xray beam produced at target of anode, exits tubehead. primary or "use-
ful" beam
4. Compton scatter evidence of ionization
xray photon collides with outer shell electron, gives up energy to eject
electron from orbit. photon loses energy and continues in different direc-
tions at lower energy. new, weaker photos interacts until all energy gone.
ejected electron + Compton, or recoil and has negative charge
- 62% of radiation
5. Coherent scatter unmodified scatter
low energy photon interacts with outer shell electron. no change in atom
and no ionization.
xray photon scattered but no loss of energy.
8% of radiation
6. Electromagnetic radi- mandmade or natural. no mass, weight or charge. travels at speed of light
ation in both a particle and a wave.
2 measurable energies are frequency and wavelength.
7. what does xray tube- where xrays are produced. sealed glass bulb with lead, all air pumped out
head consist of to create a vacuum. immersed in oil bath to insulate and dispense heat.
, TCDHA Rad theory midterm
Study online at https://quizlet.com/_ehfkkf
Cathode and Anode.
8. what does the filter of aluminum, 1.5-2.5mm thick. Filters out long wavelengths with poor pen-
xray tube do etrating power.
9. what is collimation? limits the radiation dose to the patient by limiting the amount of tissue
that is exposed
10. what does collimator Restricts the size and shape of the x-ray beam to 7cm or 2.75 inches
do
11. Maximum Accumulat- occupationally exposed workers must not exceed MAD. MAD determined
ed Dose (MAD) by age.
MAD = (N-18) x 5 rem/year
MAD = (N-18) x 0.05 Sv/year
N=age, min age 18 to work with rad
12. what is max permissi- max dose a body is permitted to receive in a specific amount of time with
ble dose? what are the little to no injury.
measurements? sv = unit of ionizing radiation
Rem = unit of radiation dosage
5-0 rem/year (0.05msv) for workers
0.1 rem(0.001msv) non workers or pregnant workers
13. 5 rules to the parallel- Film placement - cover prescribed area
ing technique Film Position: parallel to axis, toward middle of oral cavity
Vertical Angulation: central ray directed perpendicular to film
Horizontal Angulation: Central ray directed through contacts
Film Exposure: xray bean centered on film so all areas exposed
14. All size receptors - Size 0: primary posterior: placed horizontally
horizontally or vert Size 1: Mixed dentition: anterior permanent placed vertically, posterior
placed? pedo placed horizontally
, TCDHA Rad theory midterm
Study online at https://quizlet.com/_ehfkkf
Size 2: Perm dentition: Posterior placed horizontally, some perio cases
placed vertically
Size 3: Perm dentition: Posterior placed horizontally, long and narrow, all
premolars and molars captured.
15. Rules to BW Film covers RX'd area
Film positioned parallel to crowns upper and lower
Film stabilized when client occludes
Central ray of beam at +10 degrees
Central ray directed through contacts
Xray beam centered on fil to ensure all areas exposed
16. what is vertical angu- Positive for max, negative for mand. Measured in degrees on outside of
lation? Correct and in- tubehead.
correct? - PID positioned "above" occlusal plane and ray directed "downward" the
VA is POSITIVE
- PID positioned "below" occlusal plane and ray directed "upward" the VA
is NEGATIVE
Incorrect = distortion
17. What is the date xrays November 1895 by Dr. Wilhelm Conrad Roentgen
were discovered? By
whom?
18. what is free radical for- primary means by which x radiation causes cell damage.
mation? occurs when xray photon ionizes water
water ionization = hydrogen + hydroxyl free radicals
19. what is Dose Re- response and damage of tissues with the dose or amount of radiation
sponse Curve? received. no safe amount of rad, even low amounts.
20.
