true or false. All ionizing is harmful, and biological change from dental x-radiation is small, byt does still have biologic damage
both statements are true
Ionization of water results in the production of hydrogen and hydroxyl _____ _______
suggests that cell damage results when ionizing radiation directly hits critical areas, or targets within the cell (DNA)
suggests that x-ray photons are absorbed within the cell and cause the formation of toxins, which in turn damage the cell
When dose and damage of radiation are plotted on a graph, what type of relationship is seen?
true or false. there is NO safe amount of radiation, in dental radiation, damage always does occur
effects that occur as a direct function of dose; the probability of occurence increases with dose, but the severity of effects does not depend on the magnitude of the absorbed dose; they do not have a dose threshold
cancer induction and genetic mutations are what type of effects?
effects that have a threshold and increase in severity with increasing absorbed dose
erythema, loss of hair, cataract formation, and decreased fertility are examples of what effect?
Why do high dose rates cause more damage?
because the tissues don't have enough time to repair themselves
result from exposure to a nuclear accident or atomic bomb - associated with large amounts of radiation in small amounts of time
effects that appear after years and years, associated with small amounts of radiation absorbed repeatedly over a long period of time - linked to the induction of cancer, birth abnormalities, and genetic defects
long term effects
All cells in the body except the reproductive cells
effects seen in the person irradiated and not transmitted to future generations
effects not seen in the person irradiated, but passed to future generations
What are radiosensitive cells?
immature bone cells
young bone cells
What cell is most sensitive to radiation?
small lymphocyte (blood cells)
what are radioresistant cells?
cells of bone
What are radiosensitive organs?
What are radioresistant tissues?
Critical organs in dental radiography include:
lens of eye
a way of measuring radiation exposure by the amount of ionization that occurs in air
The amount of energy absorbed by a tissue; how is it measured?
rad (radiation absorbed dose)
How much radiation reduction do you get from using f-speed film?
A longer source to flim distance will _______ pts exposure to radiation
true or false. The Roentgen (R) measures the amount of energy that reaches the surface of an organism, and the amount of radiation absorbed
FALSE! It does NOT measure the amount of radiation absorbed!
SI unit that measures the number of electrical charges, or ion pairs in 1 kg of air
What measurement is used to compare the biological effects of different types of radiation?
the product absorbed dose (in rads) and quality factor specific for the type of radiation; the traditional unit of the dose equivalent
Rem - roentgen equivalent in man
a _____ _______ or dimensionless multiplier is used to place the exposure effects of different types of radiation on a common scale
SI unit equivalent of the rem is __________
SI unit equivalent of the rad is ________
a form of ionizing radiation that is ubiquitous in the environment, and which humans are exposed to daily
Radiation that originates from the stars and the sun, and the higher the elevation, the more of this you recieve
radiation that is emitted from radioactive materials present in the earth and air including potassium and uranium
What type of radiation is the single largest contributor to artificial radiation?
true or false. Risk estimates suggest that death is more likely to occur from common activities than from the dental radiographic procedures, and that cancer is far more likely to be unrelated to radiation exposure
The use of a rectangular collimator reduces absorbed radiation dose by ______ %