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Intraoral x-ray unit

Also called: x-ray tube head, x-ray machine, PID

The wall-mounted x-ray machine used for bitewings and periapical images.

The intraoral x-ray unit has a tube head on a folding arm with a cone or rectangle (the PID, position-indicating device) that you aim at the sensor in the patient's mouth. The control panel and exposure button are usually outside the room or behind a barrier. Who may take x-rays and what training is required depends on your state.

How to spot it

  • A tube head on a long jointed arm on the wall, ending in a round or rectangular cone.
  • A separate control panel with an exposure button.

What it is used for

  • Aim the PID at the sensor holder using correct angles, then step behind the barrier or at least 6 feet away to expose.
  • Follow the ADA/FDA selection guidelines the dentist uses; images are taken only when needed.

Safety and care

  • Never hold the sensor or tube head for the patient.
  • Barrier the tube head and control panel, changed after each patient, or clean and disinfect them.
  • ADA guidance (2024) no longer recommends routine thyroid collars or lead aprons; follow your state rules.

Related

Sources: CDC. Guidelines for Infection Control in Dental Health-Care Settings, 2003. MMWR 2003;52(RR-17), FDA/ADA. Dental Radiographic Examinations: Recommendations for Patient Selection and Limiting Radiation Exposure, ADA News (Feb 2024). Using thyroid collars during radiographic exams no longer recommended by ADA, Iannucci JM, Howerton LJ. Dental Radiography: Principles and Techniques, 6th ed. Elsevier, 2022