Unit 6: Clinical Operations
Clinical administration

Section 4: Dental Office Technology

Digital Radiography

In the world of evolving technology, dentistry has adopted the advances that technology has to offer, and digital radiography has become more and more common. Although film has long been an inexpensive and reliable method to capture radiographs, digital imaging offers many advantages. Digital imaging systems have proven to significantly reduce the time, expense, health risks and environmental compliance issues associated with traditional X-ray film chemical development. Wet X-ray processing exposes staff to the chemicals necessary for developing the film. These chemicals eventually reach the end of their usefulness and must be disposed of as hazardous waste, and fresh chemicals must be purchased and stocks maintained. On the other hand, digital imaging systems have significantly higher initial costs and may require substantial staff training in their use when first added to a clinic.

There are a number of significant advantages to digital radiography that are not achievable with conventional film radiography.

Advantages Disadvantages
  • Eliminates the need to purchase processing chemicals and X-ray film
  • Eliminates the need to dispose of the used processing chemicals as hazardous waste when they need replenishing
  • Eliminates the wet-film-development process and associated use of fresh water
  • Eliminates the need for silver recovery units and the associated equipment and manhours necessary to process and turn in this commodity (in some jurisdictions)
  • Reduces the number of retakes due to the ability to manipulate contrast and density with computer software
  • Significantly lowers radiation exposure
  • High initial cost
  • Large recurring maintenance costs, estimated by the U.S. Navy at 5 to 10 percent of the initial installation costs
  • Requires training for staff

Digital radiography utilizes the same projection technology as film-based radiography; however, the images are recorded by an electronic sensor. There are two main categories of intraoral sensors: direct sensor systems (charge-coupled device sensors, or CCD) and phosphor storage plates (PSP).

CCD System PSP System

  • Faster image acquisition
  • Solid state system, in which the signal is sent immediately to the computer
  • Most common technology


  • Higher cost
  • Stiffness of the sensor
  • Presence of a cord attachment between the sensor and computer, unless the wireless sensors option is selected


  • Wider exposure latitude than CCD sensors
  • Flexibility of sensor plates
  • Absence of an electrical cord


  • Additional time is necessary to readout the image
  • A readout device is required to scan the plates, adding to the cost of the system
  • Plates must be exposed to light to erase the residual image before reusing them
  • Slightly more technique-sensitive