DEA 125
Radiology I
Radiation Physics
At the completion of this lesson, the student will with at least 70% accuracy on a written
and/or oral exam:
1. Draw and label a typical atom.
2. Describe the process of ionization
3. Explain radioactivity
4. Discuss the difference between particulate radiation and electromagnetic
radiation and give two examples of each
5. Identify the electromagnetic spectrum
6. List the properties of electromagnetic radiation
7. Compare radiation wavelength to its penetrating power.
8. List the properties of radiation
9. Explain how radiation is produced
10. List and describe the possible interactions of dental radiation with matter.
11. Define the terms used to measure x-radiation
12. Explain background radiation.
13. Identify and give examples of the three types of matter
I. Matter is defined as anything that occupies space and has mass, while energy is
defined as the ability to do work and overcome resistance. In this unit, we will
see how the two work together with dental radiation.
II. Matter
A. Three types of matter
1. Gas
2. Liquid
3. Solid
III. Atomic Structure
A. 105 basic elements occurring either singly or in combination in natural
forms.
B. Elements are made up of atoms
C. An atom is the smallest form of the element that maintains the same
properties.
D. Atoms that combine with other atoms form molecules.
E. A molecule is the smallest form of a substance that retains the properties
of that substance.
F. Atoms have three basic building blocks
1. Electrons—are negatively charged and are in constant motions
orbiting the nucleus.
2. Protons—wt about 1840 times as much as an electron and have a
positive charge. The number of protons in the nucleus of of an
element determines it atomic number and is designated by the
symbol Z.
