In a comparison of DR with CR, Zaehringer et al. showed that flat panel detectors produced urograms with an image quality equivalent to or better than CR and with 50% of the radiation dose (Zaehringer et al., 2002). From: Comprehensive Biomedical
Physics, 2014 Penelope Allisy-Roberts OBE FIPEM FInstP, Jerry Williams MSc FIPEM, in
Farr's Physics for Medical Imaging (Second Edition), 2008 Computed radiography (CR) is the most common method of producing digital radiographic images and the first technology that was commercially available. CR uses a storage phosphor that requires light input to release the trapped energy in the form of light that is proportional to the X-ray intensity. It is referred to as a photostimulable phosphor. The material is commonly barium fluorohalide doped with
europium (BaFX:Eu), in which the halide (X) is a combination of bromide and iodide, typically 85% and 15%, respectively. The phosphor in a powdered form is mixed with a binder or adhesive material and laid down on a base with a thickness of about 0.3 mm. A surface coat protects the phosphor from physical damage. The imaging plate thus formed is similar in appearance to the intensifying screen used in conventional radiography. The plate is inserted into a light-tight cassette, also similar in
appearance and with the same dimensions as that used for film–screen radiography. For this reason, X-ray equipment used for conventional radiography can be used for CR, making the transition fromanalogue to digital radiography straightforward. The signal from the imaging plate is read in a CR reader. In the reader, the plate is removed from the cassette and scanned by a laser beam (see Fig. 5.5). Scanning is achieved using a
rotating mirror. Above the plate, there is an array of optical fibres to direct the emitted light to one or more photomultiplier tubes to measure its intensity. The position of the light-emitting centre is determined from the time at which the light is received. While there is repeated scanning across the plate, it is progressively moved through the scanning beam so that the complete pattern of light intensities can be extracted. Most phosphors used for CR emit light at the blue end of the
spectrum and need a scanning laser emitting red light for simulation. Following the read cycle, the residual signal from the plate is erased by exposing it to a bright light source. The time for a CR reader to extract the image from the plate is generally between about 30 and 45 s, and the faster readers are capable of reading 100 or more plates per hour. To achieve the fastest throughput, stacking readers are available in which several cassettes (at least
four) may be placed in a queue for automatic feed into the reader. Stacking readers are particularly useful for readers serving more than one X-ray room. Photostimulable phosphors have a very wide dynamic range, being able to record photon intensities varying by a factor of about 10 000:1. This is illustrated in Figure 5.6, in which the log
of the light intensity from the screen is plotted against the log of the X-ray dose. This is a linear relationship. Superimposed on the plot is the characteristic curve of a film–screen system. It can be seen how the latitude of the CR system, i.e. range of doses that can be imaged, is very much greater than for conventional radiography. If the light signal were directly converted to greyscale on an image monitor such that, for example, black was assigned to a signal level of 10 000 in the
figure and white was set at level 1, as shown by the bar above the graph, the image seen would be very flat and display minimal contrast. This is in contrast to the film, for which the greyscale is compressed into a narrower range. Effectively, the raw CR image would be equivalent to a film–screen image with a film γ (Ch. 4.2) of about 0.4 compared with 2 to 3. To display a useful image, it is
necessary to process the data from the reader. The first part of the process is to detect the collimated edges of the X-ray beam. The signal outside the collimated area is then ignored. The second stage (histogram analysis) involves an analysis of the distribution of the light intensities within the collimated area. Very high and low signals are rejected. These may correspond to areas outside the body (high pixel values) or low pixel values in the region of, for example, a metal implant
(Fig. 5.7). The third stage is to map the intensity values identified as being useful to a gradation curve that is similar in shape tothe characteristic curve of a film–screen system. However, unlike film–screen radiography, in which one curve has to be used for all radiographic projections, the shape of the curve can be optimized for the particular projection. Post-processing may also include edge enhancement and noise reduction (see
section 5.1.2). Because the parameters used in the histogram analysis and the choice of gradation curve are dependent on the projection, it is important that these are selected correctly before the image is printed or archived to the PACS. Spatial resolution with CR images is less than with conventional film–screen radiography. One factor
limiting spatial resolution is pixel size. Pixel size generally varies with plate size. For the smaller plates (18 × 24 cm2) pixel sizes are generally approximately 90 μm, implying a matrix size of 2000 × 2670 pixels (5.3 Mpixels) and limiting resolution of 5.5 lp mm−1, whereas for the largest plates (35 × 43 cm2) they are generally about 140 μm, giving a 2500 × 3070 matrix (7.7 Mpixels) with limiting resolution of about 3.5 lp mm−1. The increased size
for the larger plates is not a physical limitation. It is introduced by the manufacturer, because fine detail is not generally required for the projections for which these plates are used, such as chest and abdominal radiography. The larger pixel size helps to reduce scanning time and image file size. The values of limiting resolution may be compared with those for film–screen radiography, which are typically 8 lp mm−1 but may be increased to 12 lp mm−1 with detail
screens. There are intrinsic limits to resolution in CR other than those imposed by the choice of matrix size. The most important of these is scattering of the laser light in the phosphor layer that spreads the area over which the detected light signal is emitted. This effect increases with the thickness of the phosphor. CR phosphors are being developed that have a crystalline structure that acts as a light guide in the same way as is used in the image
intensifier input screen (see Ch. 6.1). However, such screens are more fragile and may be suitable only for use in fixed plates built into the X-ray equipment. Additional influences on spatial resolution are the size of the phosphor grains and the diameter of the scanning laser beam. High-resolution screens are available for mammography. These have a thinner phosphor layer and permit a reduced pixel size of 50 μm. The ability to detect finer
detail in the CR image may be enhanced by the partial volume effect (Ch. 7.1.1) and by the use of edge enhancement algorithms. Contrast in the CR image is determined by the processing techniques outlined in the previous section. Through the selection of gradation curves that have been optimized for the radiographic projection, the CR image should display more contrast than can be seen in film–screen
radiography. The restricted latitude of the film–screen system results in a clear indication of film dose. A dark film indicates excessive exposure and a light film underexposure. The film serves as its own quality control device. For CR and other DR systems, the detector has a very wide latitude, and processing of the data from the imaging plate ensures that the
image provided to the viewer is optimized in terms of its greyscale presentation. There is therefore no obvious indication as to whether the imaging plate has received the ‘correct’ dose; superficially, the image would look the same whether the plate had received 5 times too much or 5 times too little dose, although in the latter case quantum mottle would be apparent and could lead to unacceptable levels of low-contrast resolution. To provide assurance that
the dose to the patient is being kept as low as reasonably practicable, CR manufacturers have introduced detector dose indicators (DDIs). DDIs are analogous to optical density of film. In film–screen radiography, it would be possible to measure optical density to determine whether it was over- or underexposed, but it would be the average value determined over a broad area of the image in the region of clinical interest. In the case of film, the human eye is sufficiently accurate to assess
whether the film has an acceptable range of optical densities. In CR, DDI is determined from the signal from the plate averaged over a broad region of the plate but restricted to signal values that lie within the region of the histogram used for mapping the signal to the gradation curve (Fig. 5.7). Unfortunately, the definition of DDI is manufacturer-dependent. Some systems use a definition in which the DDI is inversely proportional to dose,
thus high DDI values indicate underexposure and vice versa. Other manufacturers have DDIs that are functions of the log of the dose. The latter case may be more intuitive, but it is important to recognize that, although high values indicate overexposure, a doubling of the dose does not double the DDI; the increase may be no more than 15%. Manufacturers provide normal ranges for DDIs that may be examination-dependent. However, it is important that radiology
departments validate these in terms of their diagnostic reference levels (see Ch. 2.6.3). The person making a CR exposure should check the DDI against the normal range to ensure that the doses given to the patient are being adequately controlled. Read full chapter URL: https://www.sciencedirect.com/science/article/pii/B9780702028441500090 Specialized ImagingIan D. McLean, Jan Martensen, in Clinical Imaging (Third Edition), 2014 Digital Radiography.Digital radiography, also known as direct digital radiography, uses x-ray–sensitive plates that directly capture data during the patient examination, immediately transferring it to a computer system without the use of an intermediate cassette as is the case with CR. Commonly referred to as plates, these flat panel detectors use a combination of amorphous silicon detectors with cesium or gadolinium scintillators that convert X-ray to light which is ultimately translated by thin film transistors into digital data (Fig. 2-38). This technology is significantly more expensive than CR technology, but the images are of the highest quality and are seamlessly sent to a computer display. These systems are popular in dedicated imaging facilities and hospitals with high workloads. Read full chapter URL: https://www.sciencedirect.com/science/article/pii/B9780323084956000026 Digital Technology in Endodontic PracticeMARTIN D. LEVIN, in Cohen's Pathways of the Pulp (Tenth Edition), 2011 Workflow Improvement: A Work MultiplierDigital radiography is a work multiplier; it replaces human effort, making tasks the practitioner and staff members perform easier and more error free. In some cases, it makes new tasks possible.19 DDR images take less time to expose, duplicate, retake, and transmit, all with less radiation and environmental impact. With solid-state systems, any operative procedure, such as endodontic therapy and implant placement, can be performed in less time. The diagnostic yield of digital imaging systems will improve as enhancements are made to image acquisition, but also to our understanding of human vision and cognition. Image processing can improve diagnostic outcomes by defining diagnostic issues and designing tools to achieve specific goals.68a Also, visual information such as digital radiography and visible light images (i.e., intraoral photography, microscopy) is easier to access than film-based images and improves office operations by increasing efficiency. PSP plates take at least 8 seconds to process after the detector is transported to the developing site and unwrapped, whereas CCD/CMOS-APS detectors are virtually instant, with “paint times” usually just a few seconds. Some workflow advantages are shown in the following comparisons.73a Read full chapter URL: https://www.sciencedirect.com/science/article/pii/B978032306489700028X Problem-Solving Techniques in Making Radiographic ImagesJames L. Gutmann DDS, Cert Endo, PhD (honoris causa), FACD, FICD, FADI, Paul E. Lovdahl DDS, MSD, FACD, FADI, in Problem Solving in Endodontics (Fifth Edition), 2011 Advances in Radiology: Digital and Cone-Beam Computed TomographyDigital radiography has revolutionized and streamlined endodontic diagnosis and treatment. There are several advantages of digital x-ray imaging over analog film imaging that can benefit the clinician5: reduced time, reduced radiation, ability to take multiple exposures without repositioning the sensor, storage and maintenance of the images, and electronic transmission of images. Clinical challenges are inability to sterilize the sensors and the thickness of sensors, which can create discomfort for some patients and difficulty in the detection of small endodontic files when radiographically determining working length (Fig. 2-41).3 When appropriately sized working length files are used, digital radiology has superior accuracy to traditional radiographic exposures. Within this perspective, and when the various capabilities of digital radiology (clear views, inverted pictures, etc.) are used to view the films (Fig. 2-42), both normal and pathologic details can be seen more clearly than on standard radiographic film16 (Fig. 2-43). An exhaustive look at digital radiography is beyond the scope of this text, but its diagnostic and treatment advantages are worth noting (Fig. 2-44). Although there are some potential technical issues with these devices, they are irrelevant to the problem-solving focus of this chapter. Scientific validation of the best exposure strategies for optimizing specific diagnostic imaging tasks in endodontics is warranted.5 There has been a major movement of cone-beam computed tomography (CBCT) into endodontics.2,11,13 This technology can be quite accurate,9,15 and its impact on diagnosis of periapical lesions and possibly their etiologies is significant4,10,14,17-19 (Fig. 2-45). Presently, cost factors for both the clinician and the patient may limit integration of this technology into private-practice settings; larger radiology centers can provide this expertise. Within 5 to 10 years, however, owing to the potential of technology to vastly improve patient care,11 CBCT may very well be considered the standard of care in providing accurate endodontic diagnoses and treatment, in particular surgical intervention and case revision.19 Read full chapter URL: https://www.sciencedirect.com/science/article/pii/B9780323068888000027 Disaster Victim IdentificationPeter W. Loomis, in Forensic Odontology, 2018 Digital Dental Radiography SensorsDigital radiography was first utilized in a DVI setting after the crash of TWA Flight 800 on July 17, 1996, when 230 lives were lost. It has since become an indispensable part of victim identification. Digital radiography can be discussed along the same lines as digital photography. Both involve sensor technology that captures either the light spectrum for photography or the X-ray spectrum for radiology. Where photography uses mega pixels to define the resolution of the sensor, radiology uses line pairs per millimeter to do the same. For a digital sensor to be equal to conventional film radiograph resolution, it should approach 22 line pairs per millimeter. As an example, this will allow the examiner to easily distinguish the tip of a number 10 endodontic file. Sensor design is important in forensic applications. The impermeable, nonflexible sensors can withstand the extreme conditions in which they are used. Sensors of different sizes have little advantage in the forensic field due to the fact that most postmortem radiologic examinations can be accomplished easier in deceased rather than living individuals. In practice, sensors with cables do pose some problems regarding breakage. At this point both the Schick sensors and the DEXIS sensors have been used to the greatest extent in DVI morgues and have proven to be effective. Comparatively, one advantage of the DEXIS software is that it can function with either sensor and has a bridge to the WinID3 dental charting and matching software for a complete dental software package. Both sensors can be used in tandem with the hand-held NOMAD or MinXray X-ray systems to allow easy movement and access in the morgue setting. The Schick sensor is thinner than the DEXIS sensor. This is because with the DEXIS sensor, the sensor electronics are located within a small dome on the back of the sensor. This increases the thickness of the sensor but also allows for the entire face of the sensor case to be available for radiation exposure. The Schick sensor is thinner but gains this by placing the sensor hardware around the outer edge of the sensor, thus reducing the exposure surface dimensions. The result is that DEXIS sensor is physically smaller than the Schick sensor, but the active exposure areas of the two are similarly sized. In large operations it has been found that these sensors are capable of taking thousands of radiographs and then being packed up and stored for the next operation. Most sensors state their life in the 200,000 exposure range. Digital radiography also can increase the quality control of the operation. Once a digital image is captured it can be reviewed in real time. This means unacceptable angulation or exposures can be corrected and retaken on the spot. It has rarely been appreciated that this capability and the elimination of the film processing cycle has accounted for the savings of hundreds (perhaps thousands) of man-hours in the dental section over the course of recent DVI operation. Digital scanners allow images or objects to be scanned and then digitized, transferred, and stored for later retrieval and review. In dental identification scenarios, scanners are usually located in the antemortem and comparison areas of the operation and allow antemortem information to be entered in a paperless digital system. All antemortem written records, photographs, conventional radiographs, and charting can be scanned into the digital record. Large format scanners can scan films all the way up to panoramic and cephalometric size films. For several years after DMORT purchased the requested digital dental equipment, its dental teams conducted regional hands-on training with the entire digital package including DEXIS sensors and specimen, networked laptops loaded with WinID, scanners and the NOMAD device. The stated goal was to improve the dental workstation efficiency by using no paper or pencils, no film, and no film processor. When Katrina occurred, that goal was effectively met. It was, in fact, a bit shocking to witness that when the morgue generator occasionally failed at the DPMU East, the dental team was able to continue their work using flashlights, a battery-operated tubehead, and a laptop also running on battery power. Read full chapter URL: https://www.sciencedirect.com/science/article/pii/B9780128051986000050 Imaging PhysicsIn Primer of Diagnostic Imaging (Fifth Edition), 2011 Digital radiography (Fig. 14-51)GeneralDigital radiography (computed radiography) replaces the screen/film system of conventional radiographic techniques by processing image data in digital (computer) rather than analog form. The essential parts of a digital radiography system are the image plate and the image reader. Any conventional x-ray system can be used for x-ray generation. For additional information, see RadioGraphics 27:675-686, 2007. Image plate (Fig. 14-52)The image plate has features similar to those of a regular screen. However, instead of rare earth elements it contains phosphor, which can be photostimulated. The phosphor consists of europium (Eu)-containing barium (Ba) fluorohalides (Eu2+:BaFX, where X is Cl, Br, I, etc.). This material changes its molecular/ionic structure by exposure to x-ray (primary stimulation), is capable of storing this information, and releases luminescence corresponding to the x-ray image when a 2nd light stimulus (reading light) is applied to the plate. Sequence of events: 1.X-ray strikes the plate 2.Eu2+ is ionized to Eu3+ 3.Electron from Eu is captured by the halide, producing a semistable F center (the x-ray is stored in this form) 4.If visible light (>500 nm, usually applied in the form of a scanning helium/neon laser) is now applied to the plate, the electron from the F center is released again. 5.Eu recaptures electron and causes luminescence (emission of blue-purple light at 400 nm). •The particle size of the Eu:BaFX in the film is 5 to 10 μm. The larger the grain, the greater the light-emitting efficiency. The smaller the grain, the sharper the image. •The luminescence of Eu:BaFX decays exponentially as soon as the reading light is turned off (half-luminescence time is 0.8 μsec) (Fig. 14-53). •Fading refers to loss of the stored x-ray information in the image plate with time. As a rule of thumb, light emission will decrease about 25% within 8 hours after acquisition of the x-ray. •The image plate is also sensitive to other forms of radiation, including gamma rays, alpha rays, beta rays, etc. Therefore, the cassettes should be kept away from other sources of radiation. Image reading (Fig. 14-54)A laser scanner is used to convert the stored information of the image plate into digital signals. The photostimulated light excited by the laser spots is directed to the photomultiplier tube by high-efficiency light guides. Binary Code
Memory128 shades of gray (or colors) require 27 bits of information. 256 shades of gray (or colors) require 28 bits of information. A 256 × 256 matrix image with 256 colors therefore requires 256 × 256 × 1 byte of storage = 65,536 bytes. Since 1 kB ≈ 1024 bytes, approximately 64 kB are needed. Likewise, a 512 × 512 matrix with 64 colors would also require 64 kB. ExampleWhat is 18 in binary code? Answer18= 16+2=000010000+000000010=000010010 Read full chapter URL: https://www.sciencedirect.com/science/article/pii/B9780323065382000147 Caution! – X-RaysNicholas Drage, Eric Whaites, in Odell's Clinical Problem Solving in Dentistry (Fourth Edition), 2021 What are the Advantages of Digital Radiography Over Film-Based Systems?The use of digital radiography has a number of advantages. One of the most important is that the image receptors are more sensitive than film, allowing a lower patient dose. In addition, image production is quicker allowing an almost immediate assessment of image quality. The images can be enhanced digitally to extract useful diagnostic information from underexposed or overexposed images and may be optimized to assess specific dental conditions such as dental caries or periodontal bone levels. Finally, electronic storage of data means that images can be accessed quickly. Digital radiography is, therefore, in the patient’s interests, with around 75% of dental practices in the UK now using digital systems. Read full chapter URL: https://www.sciencedirect.com/science/article/pii/B9780702077005000290 X-Ray and Ultrasound ImagingA. Taibi, S. Vecchio, in Comprehensive Biomedical Physics, 2014 2.05.3.2.4 x-Ray imaging performanceFigure 18 shows MTF and DQE curves for both CR and DR detectors used in mammography. Data have been taken from a very recent study that included examples of all commercially available detector technologies. Eleven digital mammography systems were included in such study: four CR systems and a group of seven DR systems, composed of three a-Se-based detectors, three cesium iodide scintillator systems, and a silicon wafer-based photon counting system. Results showed greater variation in detector MTF for the DR group compared to the CR systems and higher DQE for the DR detectors and needle CR system than for the powder CR phosphor systems. Details of the investigation can be found on the paper of Marshall et al. (2011).  Figure 18. Comparison of modulation transfer function (MTF) (left) and DQE (right) curves of x-ray detectors used in clinical mammography. Top curves: CR systems. Bottom curves: DR systems. Reproduced from Marshall NW, Monnin P, Bosmans H, Bochud FO, and Verdun FR (2011) Image quality assessment in digital mammography: Part I. Technical characterization of the systems. Physics in Medicine and Biology 56(14): 4201–4220.Read full chapter URL: https://www.sciencedirect.com/science/article/pii/B9780444536327002069 Endodontic Records and Legal ResponsibilitiesEDWIN J. ZINMAN, in Cohen's Pathways of the Pulp (Tenth Edition), 2011 Digital RadiographyDigital radiographic endodontic applications are ever increasing in accuracy.113 The standard of care does not currently require digital imaging, because traditional silver halide radiographic film is a reasonable alternative. When there is more than one reasonably acceptable practice modality, a clinician who chooses either modality meets the standard of care. Fig. 11-31, A represents a distal open margin on tooth #30 (shown digitally) that is not evident in part B with plain-film radiography. Advertised claims of 80% reduction in radiation with direct digital radiography (rather than film) assume the following37,113: 1.Ultraspeed D-speed film is used. (Ektaspeed E-speed film and the newer F-speed film reduce radiation 50% and 60%, respectively, while producing images of comparable quality to D speed.)3 2.No rectangular collimation is used, which reduces exposure another 30%. 3.No extra radiographs are taken to compensate for a smaller area. For instance, a 2 charged-coupling device (CCD) sensor has an active area smaller than size 1 film and may require an extra image with additional radiation exposure. A digital x-ray image should never be modified to “enhance” the radiographic appearance of the original image. X-ray modification can be detected; in litigation, it can be devastating to the clinician's defense. Periapical (PA) radiography is limited to only two dimensions. Newer 3D imaging systems for dental radiology use x-ray beams that are cone shaped. Cone-beam computed tomography can provide a more nearly accurate diagnosis.54,97,127 In Fig. 11-32, A-C the PA does not show the transported canal and extent of short fill, which is more evident in the CBCT. Each CBCT scan produces three image views: axial, coronal, and sagittal. CT scans enable evaluation of the true extent of lesions and their spatial relationship to important anatomic landmarks.73 Fig. 11-33, A-C shows a bifid IANC not apparent on panorexes. CT scans may provide information important for retreatment decisions, especially apical surgery. CBCT54,163,166 showed significantly more lesions than PA radiography, including expansion of lesions into the maxillary sinus, sinus membrane thickening, and missed canals; 34% of such lesions were missed by PA radiography.163,166 Artificial bone defects in the antral surface were not detected with PA radiography. Because of overlapping roots, only 1 out of 14 furcation defects in upper molars were seen on PA radiography, but CT scans were able to identify all furcal defects. Second molars proved to be the most difficult for detecting lesions with PA radiography alone. Twenty-three teeth with lesions expanding into the maxillary sinus were detected by CBCT, of which only two teeth were seen with PA radiography. Thirty-five teeth with membrane thickening were identified with CBCT, of which 16 teeth were also detected with PA radiography. Fifteen teeth with missing canals were detected with CBCT, of which only four teeth were identified with PA radiography. In a study that compared the efficacy of PA radiography and CBCT in detecting periapical lesions in maxillary premolars and molars for apical surgery,166 Lofthag-Hansen showed that 38% of maxillary posterior teeth lesions were undetected by PA radiography, despite the fact that an additional different angulated PA radiograph was taken.163 Lesions associated with apices near the sinus floor had a higher probability of being missed with PA than lesions associated with apices located away from or overlapping the sinus floor. Expansion of the lesion into the maxillary sinus, thickening of the sinus membrane, missed canals, and presence of apicomarginal communications diagnosed with CBCT were more frequently detected with CBCT than with PA radiography.163 Apicomarginal communication is an important predictor for the success rate of apical surgery including evidence of undetected vertical fractures necessitating extraction; 83% of apicomarginal communications were not seen with PA radiography in the Lofthag-Hansen study. If the radiograph shows a small distance between the periapical lesion and the sinus floor when the bony wall is thin, there is a high probability that an oral antral communication (OAC) can result, unless skillful care avoids sinus penetration during apical surgery. CBCT also allows the clinician to study the topography of the bony defect and assess whether the use of guided tissue membranes would be beneficial. Precise morphometric assessment of osseous relationships to the sinus is often inadequate with periapical radiography. Thus CBCT is invaluable in treatment planning for apical surgery, since 70% of cases studied revealed clinically relevant information not found in PA radiography.166 The probability of detecting lesions with PA alone was limited for teeth with apices in close contact with the floor of the maxillary sinus, for molars (in particular second molars), and when bone thickness between lesion and sinus was less than or equal to 1 mm. In summary, findings of lesion expansion into the sinus, sinus membrane thickening, missed canals, and presence of apicomarginal defects are more frequently diagnosed with CBCT than PA.54,166 Read full chapter URL: https://www.sciencedirect.com/science/article/pii/B9780323064897000114 Radiation Biology and Radiation SafetyP. Ortiz López, S. Carlsson, in Comprehensive Biomedical Physics, 2014 7.11.3.1.4.4 Chest radiographyFink et al. evaluated clinical chest radiographs of a large-area DR system and a conventional film-screen radiography system and found a dose reduction of 50% with the DR system (Fink et al., 2002). The same amount of reduction was found by Herrmann et al. when comparing the performance of cesium iodide (CsI)-doted amorphous silicon (a-Si) DR technology with CR technology in depicting relevant anatomical structures in chest radiography (Herrmann et al., 2002). Bacher et al. showed that both entrance skin dose and effective dose from chest radiography with an amorphous silicon DR system were a factor of 2.7 lower than that from film-screen radiography and 1.7 lower than that from a CR system and concluded that DR offers improved image quality combined with a significant radiation dose reduction (Bacher et al., 2003). Read full chapter URL: https://www.sciencedirect.com/science/article/pii/B978044453632700811X What is an advantage of digital imaging over film based radiographic imaging?Better Image Quality
To be able to make a proper diagnosis and provide the needed treatment, clarity and details in dental imaging is very important. Digital x-rays provide a much higher image quality than that of traditional film.
What are the advantages of digital imaging technology?The Benefits of Digital Imaging and Impressions
Impressions are stored electronically for easy access. Issues may be diagnosed immediately, as no time is needed for processing images. Precise imaging allows for improved fit of restorations. Saves time for the patient and dentist.
What is the difference between digital and film radiography?Benefits of Digital Radiography
The film is immediately processed and available to view, whereas film takes time to be developed. Less radiation needed to produce the same quality image as film (digital X-rays gives 70% less exposure to radiation than conventional X-rays).
Which of the following is an advantage of digital radiology?Answer and Explanation: The advantage of digital radiology is providing high-quality images, the images are saved on CD or DVD, the images captured during this process are...
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Which is an advantage of digital imaging systems compared to traditional film-screen systems?
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