1. Copyright © 2012, 2006, 2000, 1996 by Saunders, an imprint of Elsevier Inc. 1 Digital Imaging Instead of Radiography

2. Copyright © 2012, 2006, 2000, 1996 by Saunders, an imprint of Elsevier Inc. 2 Basic Concepts of Digital Imaging Used to record dental images Used to record dental images No film or processing chemistry is used No film or processing chemistry is used Uses an electronic sensor and computerized imaging system that produces x-ray images almost instantly on a computer monitor Uses an electronic sensor and computerized imaging system that produces x-ray images almost instantly on a computer monitor Uses reusable phosphor plates to produce x- ray images almost instantly on a computer monitor Uses reusable phosphor plates to produce x- ray images almost instantly on a computer monitor

3. Copyright © 2012, 2006, 2000, 1996 by Saunders, an imprint of Elsevier Inc. 3 Digital Imaging Terminology Charge-coupled device Charge-coupled device CCD / an image receptor found in the intraoral sensor, which converts x-rays to electrons CCD / an image receptor found in the intraoral sensor, which converts x-rays to electrons Digital radiography Digital radiography A filmless imaging system that uses a sensor and a computer to acquire, process, store, retrieve and display the radiographic image A filmless imaging system that uses a sensor and a computer to acquire, process, store, retrieve and display the radiographic image Digital subtraction Digital subtraction Digitally merging two images to show changes that occur over time Digitally merging two images to show changes that occur over time Direct digital imaging Direct digital imaging A method of directly obtaining a digital image by exposing an intraoral sensor to x-rays to produce an image viewed on a computer monitor A method of directly obtaining a digital image by exposing an intraoral sensor to x-rays to produce an image viewed on a computer monitor Indirect digital imaging Indirect digital imaging A method of obtaining a digital image in which an existing radiograph is scanned or photographed and then converted into a digital image A method of obtaining a digital image in which an existing radiograph is scanned or photographed and then converted into a digital image Digitize Digitize To convert a film based image into a digital form that can be processed by a computer To convert a film based image into a digital form that can be processed by a computer

4. Copyright © 2012, 2006, 2000, 1996 by Saunders, an imprint of Elsevier Inc. 4 Digital Imaging Terminology Digital image Digital image Bits of information in a computer file which tell the computer how to construct an image on a monitor or other viewing device Bits of information in a computer file which tell the computer how to construct an image on a monitor or other viewing device Pixel Pixel Picture element/ units of information that together constitute an image Picture element/ units of information that together constitute an image Spatial resolution Spatial resolution Separation of closely adjacent image details Separation of closely adjacent image details Sensor Sensor An electronic device sensitive to x-rays that captures a radiographic image and allows it to be displayed on the monitor An electronic device sensitive to x-rays that captures a radiographic image and allows it to be displayed on the monitor Storage phosphor imaging Storage phosphor imaging Use of reusable phosphor plates to record digital image Use of reusable phosphor plates to record digital image

5. Copyright © 2012, 2006, 2000, 1996 by Saunders, an imprint of Elsevier Inc. 5 Purpose and Use The same as radiography but with less radiation and less hazardous chemicals The same as radiography but with less radiation and less hazardous chemicals To generate images that can be used in the diagnosis and assessment of dental disease To generate images that can be used in the diagnosis and assessment of dental disease

6. Copyright © 2012, 2006, 2000, 1996 by Saunders, an imprint of Elsevier Inc. 6 Fundamentals Digital imaging Digital imaging A method of capturing a radiographic image using a sensor, breaking it into electronic pieces, and presenting and storing the image using a computer A method of capturing a radiographic image using a sensor, breaking it into electronic pieces, and presenting and storing the image using a computer Image used to describe the pictures that are produced Image used to describe the pictures that are produced A sensor placed inside the mouth A sensor placed inside the mouth The electronic signal is digitized The electronic signal is digitized

7. Copyright © 2012, 2006, 2000, 1996 by Saunders, an imprint of Elsevier Inc. 7 Radiation Exposure The typical sensor is more sensitive to x- rays than conventional film. The typical sensor is more sensitive to x- rays than conventional film. Exposure times are 50% to 80% less than that required for conventional radiography depending the film speed being used Exposure times are 50% to 80% less than that required for conventional radiography depending the film speed being used

8. Copyright © 2012, 2006, 2000, 1996 by Saunders, an imprint of Elsevier Inc. 8 Equipment X-radiation source X-radiation source Most conventional dental x-ray units work with digital Most conventional dental x-ray units work with digital The x-ray unit timer must be adapted to allow exposures in a time frame of 1/100 of a second. The x-ray unit timer must be adapted to allow exposures in a time frame of 1/100 of a second. Three common image detectors Three common image detectors Charge-coupled device (CCD) sensor Charge-coupled device (CCD) sensor Complementary metal oxide semiconductor/active pixel sensor (CMOS) sensor Complementary metal oxide semiconductor/active pixel sensor (CMOS) sensor Photo stimuable phosphor (PSP) phosphor plate Photo stimuable phosphor (PSP) phosphor plate Computer Computer Hardware required is based on digital imaging software being used Hardware required is based on digital imaging software being used

9. Copyright © 2012, 2006, 2000, 1996 by Saunders, an imprint of Elsevier Inc. 9 Intraoral Sensor A small detector that is placed in the mouth of the patient and used to capture the radiographic image A small detector that is placed in the mouth of the patient and used to capture the radiographic image Wired Wired The imaging sensor is linked by a fiber optic cable to a computer. The imaging sensor is linked by a fiber optic cable to a computer. Wireless Wireless The imaging sensor is not linked by a cable. The imaging sensor is not linked by a cable.

10. Copyright © 2012, 2006, 2000, 1996 by Saunders, an imprint of Elsevier Inc. 10 Charge-Coupled Device (CCD) The most common image receptor used in dental digital imaging The most common image receptor used in dental digital imaging A solid-state detector that contains a silicon chip with an electronic circuit embedded in it A solid-state detector that contains a silicon chip with an electronic circuit embedded in it The electrons that make up the silicon CCD can be visualized as being divided into an arrangement of blocks or picture elements known as pixels The electrons that make up the silicon CCD can be visualized as being divided into an arrangement of blocks or picture elements known as pixels Pixel Pixel A small box or “well” into which the electrons produced by the x-ray exposure are deposited A small box or “well” into which the electrons produced by the x-ray exposure are deposited

11. Copyright © 2012, 2006, 2000, 1996 by Saunders, an imprint of Elsevier Inc. 11 Charge-Coupled Device (CCD) The x-ray photons that come into contact with the CCD cause electrons to be released from the silicon and produce a corresponding electronic charge. The x-ray photons that come into contact with the CCD cause electrons to be released from the silicon and produce a corresponding electronic charge. Each pixel arrangement, or electron potential well, contains an electronic charge proportional to the number of electrons that reacted within the well. Each pixel arrangement, or electron potential well, contains an electronic charge proportional to the number of electrons that reacted within the well. Each electronic well corresponds to a specific area on the linked computer screen. Each electronic well corresponds to a specific area on the linked computer screen.

12. Copyright © 2012, 2006, 2000, 1996 by Saunders, an imprint of Elsevier Inc. 12 Complementary Metal Oxide Semiconductor/Active Pixel Sensor (CMOS/APS) One manufacturer uses a CMOS/APS sensor instead of a CCD. One manufacturer uses a CMOS/APS sensor instead of a CCD. The chip is less expensive to produce and offers greater durability than the CCD. The chip is less expensive to produce and offers greater durability than the CCD.

13. Copyright © 2012, 2006, 2000, 1996 by Saunders, an imprint of Elsevier Inc. 13 Computer Used to store the incoming electronic signal Used to store the incoming electronic signal Converts the electronic signal from the sensor into a shade of gray that is viewed on the computer monitor Converts the electronic signal from the sensor into a shade of gray that is viewed on the computer monitor The computer digitizes, processes, and stores information received from the sensor The computer digitizes, processes, and stores information received from the sensor An image is recorded on a computer monitor in 0.5 to 120 seconds An image is recorded on a computer monitor in 0.5 to 120 seconds Has split screen and magnification capability. Has split screen and magnification capability.

14. Copyright © 2012, 2006, 2000, 1996 by Saunders, an imprint of Elsevier Inc. 14 Types of Digital Imaging Direct Digital Imaging Direct Digital Imaging Indirect Digital Imaging Indirect Digital Imaging Scanning traditional radiographs Scanning traditional radiographs Storage phosphor imaging Storage phosphor imaging

15. Copyright © 2012, 2006, 2000, 1996 by Saunders, an imprint of Elsevier Inc. 15 Direct Digital Imaging Components include an x-ray machine, an intraoral sensor, and computer monitor Components include an x-ray machine, an intraoral sensor, and computer monitor A sensor is placed into the mouth of the patient and exposed A sensor is placed into the mouth of the patient and exposed The sensor captures the radiographic image and transmits it to the computer monitor The sensor captures the radiographic image and transmits it to the computer monitor Software is used to enhance and store the image Software is used to enhance and store the image

16. Copyright © 2012, 2006, 2000, 1996 by Saunders, an imprint of Elsevier Inc. 16 Indirect Digital Imaging Components include a CCD camera and a computer. Components include a CCD camera and a computer. An existing x-ray film is digitized using a CCD camera. An existing x-ray film is digitized using a CCD camera. The image is displayed on a computer monitor. The image is displayed on a computer monitor.

17. Copyright © 2012, 2006, 2000, 1996 by Saunders, an imprint of Elsevier Inc. 17 Storage Phosphor Imaging A wireless digital imaging system A wireless digital imaging system This is a reusable imaging plate coated with phosphors is used instead of a sensor with a fiber optic cable. This is a reusable imaging plate coated with phosphors is used instead of a sensor with a fiber optic cable. The phosphor-coated plates are flexible and fit into the mouth. The phosphor-coated plates are flexible and fit into the mouth. A high-speed scanner is used to convert the information into electronic files. A high-speed scanner is used to convert the information into electronic files. This type of digital imaging is less rapid than direct digital imaging. This type of digital imaging is less rapid than direct digital imaging.

18. Copyright © 2012, 2006, 2000, 1996 by Saunders, an imprint of Elsevier Inc. 18 Step-by-Step Procedures It is critical to refer to the manufacturer-provided instruction booklet for information concerning the operation of the system, equipment preparation, patient preparation, and exposure. It is critical to refer to the manufacturer-provided instruction booklet for information concerning the operation of the system, equipment preparation, patient preparation, and exposure.

19. Copyright © 2012, 2006, 2000, 1996 by Saunders, an imprint of Elsevier Inc. 19 Sensor Preparation Each sensor is sealed and waterproof. Each sensor is sealed and waterproof. The sensor must be covered with a disposable barrier because it cannot be sterilized. The sensor must be covered with a disposable barrier because it cannot be sterilized.

20. Copyright © 2012, 2006, 2000, 1996 by Saunders, an imprint of Elsevier Inc. 20 Sensor Placement The sensor is held in the mouth by bite- block attachments or devices that aim the beam and sensor accurately. The sensor is held in the mouth by bite- block attachments or devices that aim the beam and sensor accurately. The paralleling technique is the preferred exposure method. The paralleling technique is the preferred exposure method.

21. Copyright © 2012, 2006, 2000, 1996 by Saunders, an imprint of Elsevier Inc. 21 Advantages of Digital Imaging Superior gray-scale resolution Superior gray-scale resolution 256 shades of gray versus <25 shades on film 256 shades of gray versus <25 shades on film Reduced exposure to x-radiation Reduced exposure to x-radiation 50% less than F speed film 50% less than F speed film 80% less than D speed film 80% less than D speed film Increased speed of image viewing Increased speed of image viewing Instant image versus 10 minute processing with possible errors Instant image versus 10 minute processing with possible errors Lower equipment and film cost Lower equipment and film cost No film cost, no processors or solution cost No film cost, no processors or solution cost Increased efficiency Increased efficiency Less chance of error Less chance of error Enhancement of diagnostic image Enhancement of diagnostic image Image can be manipulated by software options Image can be manipulated by software options Effective patient education tool Effective patient education tool Easier to show to patient because of size on computer screen Easier to show to patient because of size on computer screen

22. Copyright © 2012, 2006, 2000, 1996 by Saunders, an imprint of Elsevier Inc. 22 Disadvantages of Digital Imaging Initial set-up costs Initial set-up costs Could cost in the ball park of $15,000 – $20,000 Could cost in the ball park of $15,000 – $20,000 Image quality Image quality Some operators preferred film images Some operators preferred film images Sensor size Sensor size Bulkiness of sensors can be uncomfortable for patients Bulkiness of sensors can be uncomfortable for patients Infection control Infection control Cannot be heat sterilized Cannot be heat sterilized Barriers tear and become contaminated during procedure Barriers tear and become contaminated during procedure Legal issues Legal issues Images can be manipulated therefore can they be used as evidence in court of law? Images can be manipulated therefore can they be used as evidence in court of law?