Upgrade to remove ads
Only $2.99/month

Rad 4

Terms in this set (36)

(1) All ionizing radiation cause damage to living tissues. (2) Although very little radiation is used in dentistry, damage to the cells does occur.
Both statements are true
What specific mechanism of radiation injury may result in the formation of hydrogen peroxide when x-ray energy is absorbed by patients?
Free radical formation created by the ionization of water may occur.
Which of the following statements is true regarding the direct theory of radiation injury?
It involves damage to the critical areas of a cell through direct contact with the x-ray photon.
The indirect theory proposes that
Toxins are created from the formation of free radicals
According to the dose-response curve, when dose and damage are plotted on a graph, a _________ relationship is seen?
Linear, nonthreshold
A non-threshold dose-response curve suggests that.
Radiation exposure, no matter how small, causes damage to living tissue.
Stochastic biologic effects from radiation
Occur as a result of exposure, but severity is not determined by dose.
Which of the following is an example of stochastic effects?
Cancer
Your patient was out in the hot, bright sun yesterday. While in the sun she began experiencing pain and noticed her skin had turned bright red. Shortly after arriving home, she began to experience chills, nausea, severe pain and blistering. Why would your patient experience the symptoms so quickly?
The latent period was decreased by the increased dose and dose rate
Cellular injuries following the latent period may include (1) cell death (2) cessation of mitotic activity and or (3) abnormal atomic activity
1,2,3
_______refers to the total amount of radiation that is received or absorved
Total dose
(1) More radiation damage takes place with high dose rates (2) because a rapid delivery of radiation does not allow time for cellular damage to be repaired
Both statements are true
Which types of cells are more sensitive to radiation: (1) rapidly dividing (2) slowly dividing (3) young or (4) old
1 and 3
Which of the following is associated with long term radiation effects?
Small amounts of radiation absorbed over a long period
Which of the following is a sign or symptom of acute radiation of acute radiation syndrome (ARS)?
Hair loss
Which of the following statements is true of somatic effects of irradiation
Changes are not transmitted to future generations
Which of the following cells would be the most sensitive to x-rays?
Blood
Which of the following is the least sensitive to x-rays
Salivary glands
Precautions should be taken during dental imaging procedures to which of the following critical organs in the head and neck region?
1,2,3,4
The traditional unit of dose is called
The radiation absorbed dose (rad)
One gray is equivalent to ___ rad(s)
100
The SI equivalent of the rem is
The sievert
You could be exposed to each of these radiation sources in your daily activities. Which of theses sources is human-made?
Atomic fallout
Uranium is an example of ______ radiation
Terrestial
________ is/are the single largest contributor to artificial radiation exposure (0.00053 Sv/year).
Medical radiation
Which of the following statements is true of the average dose of background radiation received by an individual in the US?
Geographic areas at higher elevations are associated with increased amounts of cosmic radiation.
The potential risk of dental radiography inducing a fatal cancer in an individual is about _______ the risk of a person developing cancer spontaneously.
1/1,000,000
A 1 in 1 million risk of a fatal outcome is associated with which of the following activities?
All three of the above activities.
Risk estimates suggest (1) that death is more likely to occur from common activities than from dental imaging procedures and (2) that cancer is much more likely to be unrelated to dental imaging radiation exposure
Both statements are true
The use of F- speed film instead of D- speed film reduces the absorbed dose by ____%
60
Your patient is concerned about radiation exposure. Which of the following explanations would you give to your patient to help calm her concerns
I am using this collimator attachment, which will decrease the x-ray dose you receive by 60-70%
Which of the following combinations will result in the lowest absorbed dose for the patient from a 20-film series of dental radiographs?
Rectangular collimation with digital sensor
Your patient is receiving radiation treatment for breast cancer. She reports having a burning sore throat and great difficulty swallowing. Which stage of the radiation injury sequence is your patient in
Injury
Your patients is concerned about being exposed to dental x-rays. Which of the following could you tell your patient
The risks from dental imaging are not significantly greater than the risks of other everyday activities in modern life.
Explain to your patient the steps, in order, in the formation of hydrogen peroxide, a toxin that will cause damage to living tissues
1. Free radicals combine
2.free radical formation
3.cellular dysfunction and biologic damage
4. X-ray photons are absorbed by water.
4,2,1,3
The bombing at Nagasaki and Hiroshima took place in 1945; an increase in the incidence of cancer was noted in 1956. Which effects apply to the cancer incidence?
Long term, somatic
THIS SET IS OFTEN IN FOLDERS WITH...