Final Exam Review Flashcards
Two ways to maintain cleanliness in the office?
Barriers
Disinfectant
Equivalent and effective doses are measured in what?
Sieverts, or micro sieverts
What is the absorbed dose?
Energy deposited in a kg of a substance
Grays
What is the equivalent dose?
Absorbed dose weighted for harmful effects of different radiations (Type of radiation)
Sieverts
What is the effective dose?
Equivalent dose weighted for susceptibility to harm of different tissues (Types of tissues)
Sieverts
What has high radiosensitivity?
Lymphoid organs
Bone marrow
Testes
Intestine
Mucous membranes
What has intermediate radiosensitivity?
Fine vasculature
Growing cartilage
Salivary glands
Lungs
Kidney
Liver
What has low radiosensitivity?
Optic lens
Muscle
What is the deterministic effect?
THIS HAS A THRESHOLD
Below the threshold - No damage
Above the threshold - Damage
—Blistering, burns
What is the stochastic effect?
Arrows
NO THRESHOLD
One X-ray can cause an issue
More radiation that is received, the statistical probability of being injured goes up
What has a lower effective dose, rectangular or circular collimator?
Rectangular collimation
T/F - A digital pano has a lower effective dose than a digital FMX with rectangular collimation.
TRUE
High altitudes equal what in terms of radiation?
Higher radiation levels
What is ALARA?
As Low As Reasonably Achievable
What are three guidelines for radiation?
Justification
ALARA
Dose limitation
Radiation Quality Assurance things to know.
UT inspects dental X-ray units and their use environment every 5 years!
Dosimeters calculations are completed and checking of machines are done as well
Radiation safety program should be developed and followed utilizing information derived from these inspections
The negative part of the X-ray tube is called the ___________.
The positive part of the X-ray tube is called the _________.
Cathode
Anode
T/F - The X-ray tube has a tungsten target.
TRUE
T/F - The X ray tube is in a vacuum state to prevent oxidation and burnout of filament.
TRUE
Cathode is high or low voltage?
Anode is high or low voltage?
Cathode - LOW
Anode - HIGH - If machine is 60 kVp, that goes into effect here
What does the cathode create?
Electron cloud
What does the step down filament transformer do?
Reduces 110 V from wall to 3-5 volts to heat the filament
What does the step-up transformer do?
Provides the large force needed to proper electrons from cathode to anode
What is the SLOB rule?
Same lingual, Opposite buccal
Take the X-ray, and then move the tube mesial and take again and look at the object in question
The denser the object, the more radio_______.
OPAQUE
