1. Reference Reading Chapter 2: pp. 15 - 17

2.  X-rays are produced within the dental x-ray machine  The x-ray machine can be divided into 3 study areas ◦ Component Parts ◦ The x-ray tube ◦ X-ray generating apparatus

3.  The Dental x-ray machine consists of 3 visible component parts: ◦ The Control Panel ◦ The Extension Arm ◦ The Tubehead

5.  The Control Panel contains: ◦ On-off switch and an indicator light ◦ The exposure button and an indicator light ◦ Control devices to regulate the x-ray beam  Time setting  kVp setting  mA setting

6. Older styleNewer Design

7.  The extension arm suspends the x-ray tubehead and houses the electrical wires that extend from the control panel to the tubehead  The extension arm allows for movement and positioning of the tubehead

8.  The tubehead is a tightly sealed, heavy metal housing that contains the x-ray tube. The x-ray tube produces the dental x- rays

9.  The component parts of the tubehead include: ◦ Metal housing ◦ Insulating oil ◦ Tubehead seal ◦ X-ray tube ◦ Transformer ◦ Aluminum disk/filter ◦ Lead collimator ◦ Position Indicating Device (P.I.D.)

10. Metal Housing  The Metal Housing, or body, of the tubehead surrounds the x-ray tube and is filled with oil.  It protects the x-ray tube and grounds the high voltage components.

11.  Insulating Oil – the oil that surrounds the x- ray tube.  It prevents overheating by absorbing the heat created when x-rays are produced

12.  Tubehead Seal – the aluminum or leaded glass covering of the tubehead that permits the exit of x-rays from the tubehead.  It seals the oil in the tubehead

13.  The X-ray tube – the heart of the x-ray generating system.

14.  Aluminum Disks – sheets of 0.5 mm aluminum placed in the path of the x-ray beam.  This filters out the longer wavelength, non-penetrating x- rays.  Text – p. 15, Fig. 2-14

15.  Lead Collimator – a lead plate with a central hole that fits directly over the opening of the metal housing where the x- rays exit the tubehead.  Restricts the size of the x-ray beam to 2.75 inches at the patient’s face.

16. Different tubehead lengths  Position Indicating Device (P.I.D.) – aims and shapes the x-ray beam as it exits the tubehead.  Sometimes called the “cone”

17.  Cathode is the negative electrode of the x-ray tube.  The purpose of the electrodes is to supply the electrons necessary to generate x-rays.  The cathode consists of: ◦ Tungsten filament- generates the electrons that produce the x-rays at the tungsten target ◦ Molybdenum cup

18.  The anode is the positive electrode within the x-ray tube  The purpose of the anode is to convert the electrons into x-ray photons at the tungsten target.  The anode consists of: ◦ The tungsten target ◦ The copper stem