Dentistry Chapter 3 The Quantity The X Rays Produced Controlled Milliamperage

Dental Radiography: Principles and Techniques, 5th Edition

Chapter 3 Student Handout

Slide 1

Radiation Characteristics

Chapter 3

___________________________________

Slide 2

Learning Objectives

Lesson 3.1: Radiation

Characteristics

1. Define the key terms associated with radiation

characteristics.

___________________________________

Slide 3

Learning Objectives

Lesson 3.1: Radiation

Characteristics (Cont.)

5. Describe how milliamperage affects the density

of the image and how exposure time and

milliamperage are related.

___________________________________

Dental Radiography: Principles and Techniques, 5th Edition

Chapter 3 Student Handout

Slide 4

Introduction

Purpose

To detail the concepts of x-ray beam quality and

___________________________________

Slide 5

X-Ray Beam Quality

Voltage and kilovoltage

___________________________________

Slide 6

X-Ray Beam Quality (Cont.)

___________________________________

Dental Radiography: Principles and Techniques, 5th Edition

Chapter 3 Student Handout

Slide 7

Voltage and Kilovoltage

Voltage

Potential difference between two electrical

charges

___________________________________

Slide 8

Voltage and Kilovoltage (Cont.)

Voltage is measured in volts or kilovolts.

Volt

___________________________________

Slide 9

Kilovoltage Peak (kVp)

Maximum or peak voltage

___________________________________

Dental Radiography: Principles and Techniques, 5th Edition

Chapter 3 Student Handout

Slide 10

Density and Kilovoltage Peak

Density

This is the overall darkness or blackness of an

___________________________________

Slide 11

Contrast and Kilovoltage Peak

Contrast

How sharply dark and light areas are differentiated

on an image

___________________________________

Slide 12

Exposure Time and Kilovoltage Peak

Exposure time

___________________________________

Dental Radiography: Principles and Techniques, 5th Edition

Chapter 3 Student Handout

Slide 13

X-Ray Beam Quantity

Amperage and milliamperage

___________________________________

Slide 14

Amperage and Milliamperage

Amperage

Determines the amount of electrons passing

through the cathode filament

Increasing amperage

___________________________________

Slide 15

Amperage and Milliamperage (Cont.)

Ampere (A)

Unit of measure used to describe the number of

electrons, or current flowing through the cathode

___________________________________

Dental Radiography: Principles and Techniques, 5th Edition

Chapter 3 Student Handout

Slide 16

Amperage and Milliamperage (Cont.)

Milliamperage

Milliamperage regulates the temperature of the

___________________________________

Slide 17

Milliampere-Seconds (mAs)

mAs is the product of milliamperes and

exposure time.

___________________________________

Slide 18

Density and Milliamperage

An increase in milliamperage

Increases overall density of the image

Results in a darker image

18

___________________________________

Dental Radiography: Principles and Techniques, 5th Edition

Chapter 3 Student Handout

Slide 19

Exposure Time and Milliamperage

An inverse relationship

When milliamperage is increased, exposure time

___________________________________

Slide 20

Exposure Factor Tips

All dental x-ray machines have three exposure

___________________________________

Slide 21

X-Ray Beam Intensity

Kilovoltage peak

Milliamperage

___________________________________

Dental Radiography: Principles and Techniques, 5th Edition

Chapter 3 Student Handout

Slide 22

X-Ray Beam Intensity (Cont.)

___________________________________

Slide 23

Kilovoltage Peak

Regulates the penetrating power of the x-ray

beam by controlling the speed of electrons

___________________________________

Slide 24

Milliamperage

Controls the penetrating power of the x-ray

___________________________________

Dental Radiography: Principles and Techniques, 5th Edition

Chapter 3 Student Handout

Slide 25

Exposure Time

Exposure time affects the number of x-rays

___________________________________

Slide 26

Distance

The distance traveled by the x-ray beam

affects the intensity of the beam.

___________________________________

Slide 27

Distance (Cont.)

As x-rays travel from their point of origin, they

___________________________________

Dental Radiography: Principles and Techniques, 5th Edition

Chapter 3 Student Handout

Slide 28

Inverse Square Law

The intensity of radiation is inversely

proportional to the square of the distance

___________________________________

Slide 29

Half-Value Layer

Aluminum filters are placed in the path of the

beam inside the dental x-ray tubehead.

___________________________________

Slide 30

Questions?

30

___________________________________