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Sample records for panoramic dental radiography

  1. Panoramic Dental X-Ray

    MedlinePlus

    ... X-ray? What is Panoramic X-ray? Panoramic radiography , also called panoramic x-ray , is a two- ... Exams Dental Cone Beam CT X-ray, Interventional Radiology and Nuclear Medicine Radiation Safety About this Site ...

  2. Panoramic dental radiography using a charge-coupled device receptor.

    PubMed

    Farman, A G; Farman, T T

    1998-08-01

    Panoramic radiography using a slit beam and film/screen receptor is standard for the emergency room evaluation of mandibular fractures and also in dentistry. This study compared the spatial resolution, area distortion factors, and the dosage considerations for a panoramic system where standard film/screen and a charge-coupled device were alternatively employed as the image receptor. Resolution and image contours were determined using a lead resolution grid positioned at selected beam projection angulations. Exposure measurements were carried out using a RANDO average man phantom and a 3 cc beryllium-windowed ionization chamber. The maximum spatial resolution with film approached 5 lp mm-1 whereas with the CCD the maximum resolution was just above 4 lp mm-1. Consequently, the image layer was reduced slightly in width when using the CCD receptor. The use of the CCD resulted in skin exposure reduction exceeding 70%. PMID:9735460

  3. Dental Patterns in Peruvians: A Panoramic Radiography Study.

    PubMed

    Perez, Ivan E

    2015-12-01

    The dental pattern is defined as the combination of distinct codes assigned to describe specific tooth conditions including virgin, missing, and restored teeth that comprise the complete dentition or from discrete groups of teeth. This pattern can be then compared to the dentition of individual/s in an attempt to determine positive identification. The aims of the present investigation were to study and determine the diversity of dental patterns in Peruvian citizens based on a sample of panoramic radiographs. Digital panoramic radiographs of 900 adult Peruvian patients (450 female and 450 male) were evaluated to determine the dental patterns. The most frequent dental patterns found in the complete dentition, maxillae, upper-anterior and lower-anterior sextants were all-virgin-teeth (0.3%), all-extracted teeth (1.9%), all-virgin teeth (1%) and all-virgin-teeth (34.2% and 72.3%) respectively. The diversity was calculated by the use of the Simpson's diversity index, the resulting values for the full-dentition, maxilla and mandible were over the 99.8% value and were similar to those previously reported in the scientific literature. This study demonstrates the positive benefit of dental patterns in the process of identification. Additionally a combination of codes is proposed that could prove useful in cases where a better radiographic description is required. PMID:26851634

  4. Panoramic dental radiography image intensification employing minification techniques

    SciTech Connect

    Cushman, R.H.

    1981-09-01

    Panoramic dental x-ray machine wherein an x-ray source-camera assembly orbits a seated patient is described. A slot in the camera assembly collimates the x-rays which are continuously generated by the x-ray source, which x-rays are converted to light images of the patient's dental arch structure by only a single intensifying screen which remains stationary. This screen comprises about 1/40 the area of conventional intensifying screens and is made thicker for providing improved detection efficiency. A fiber optic minifying lens reduces the size of the image from the screen while proportionately increasing the light intensity of the image, thus making it possible to provide useable film images at reduced x-ray exposures due to non-linear film exposure versus optical density characteristics. The resultant minified, light-intensified image may now be recorded on 35 mm roll film, for example, as opposed to standard radiographic film of 5'' X 12'' size, or 12.70 cm X 30.48 cm.

  5. Image quality assessment in panoramic dental radiography: a comparative study between conventional and digital systems

    PubMed Central

    Tiau, Yu Jin

    2013-01-01

    This study is designed to compare and evaluate the diagnostic image quality of dental panoramic radiography between conventional and digital systems. Fifty-four panoramic images were collected and divided into three groups consisting of conventional, digital with and without post processing image. Each image was printed out and scored subjectively by two experienced dentists who were blinded to the exposure parameters and system protocols. The evaluation covers of anatomical coverage and structures, density and image contrast. The overall image quality score revealed that digital panoramic with post-processing scored the highest of 3.45±0.19, followed by digital panoramic system without post-processing and conventional panoramic system with corresponding scores of 3.33±0.33 and 2.06±0.40. In conclusion, images produced by digital panoramic system are better in diagnostic image quality than that from conventional panoramic system. Digital post-processing visualization can improve diagnostic quality significantly in terms of radiographic density and contrast. PMID:23483085

  6. Dosimetric study of the effective doses resulting during dental X-ray and panoramic radiography

    NASA Astrophysics Data System (ADS)

    Shousha, Hany A.; Abd-El Hafez, A. I.; Ahmad, Fawzia

    2011-01-01

    The panoramic image is one of the most commonly used radiographic examinations in dentistry, owing to its low dose and large area for evaluation, including bone and teeth in the same image. Although digital images are usually reported to deliver a lower radiation dose to the patient, conventional images are still available, especially in countries where digital systems are not widely economically available. Dentists should weigh the benefits of dental radiographs against the consequences of increasing a patient's exposure to radiation, the effects of which accumulate from multiple sources over time. The "as low as reasonably achievable" principle should be followed to minimize the exposure to radiation. The purpose of this investigation is to measure the absorbed radiation doses at 12 anatomical sites of a Rando-phantom and calculate the effective doses result from a full-mouth survey and panoramic radiography. Organ-absorbed doses are measured using thermoluminescent dosimeters (TLD 100) and effective organ doses (μ Sv) are estimated according to the International Commission on Radiological Protection in 2007. The total effective dose results from the panoramic imaging system have so far been below those obtained using the full-mouth survey technique used in intra-oral radiographic examination.

  7. Correlation of dental pulp stones, carotid artery and renal calcifications using digital panoramic radiography and ultrasonography

    PubMed Central

    Yeluri, Garima; Kumar, C. Anand; Raghav, Namita

    2015-01-01

    Background: The human tissues continuously undergo modification as deposition of calcium (CA) salts either in an organized or disorganized pattern. The latter pattern usually occurs in the soft tissues such as in arteries, brain, kidneys, lungs, and dental pulp. The purpose of this study is to evaluate the presence of pulp calcification and carotid artery calcification (CDC) as a marker for renal calcification and altered serum biomarkers such as serum CA, phosphorus (P), and alkaline phosphatase (ALP). Materials and Methods: Digital panoramic radiographs of 50 patients with the presence of pulp stones and suspected CAC were subjected to carotid artery and renal ultrasonography (USG) examination for the presence of vascular calcification and also to evaluate the alterations in serum CA, P, and ALP levels. Data were analyzed statistically using Chi-square test. Results: Panoramic radiographs of 50 patients showed 88.28% of teeth with the presence of pulp stones stones and 91% carotid arteries with calcification. The sensitivity of panoramic radiograph was greater than that of USG (93.67%), but the specificity of USG was more than the panoramic radiograph (44.44%) in detecting CAC. The prevalence rate of renal calcification on USG was 92%. The statistical difference between the patients with or without alteration in serum Ca levels was not significant (χ2 = 0.581 and P = 0.446). On comparison of serum P and ALP, the difference was found to be statistically significant. Conclusion: Presence of pulp stones and CAC's on panoramic radiograph have remarkably proved to establish the chances of renal artery calcification associated with alterations in serum CA levels. PMID:26604565

  8. Establishment of diagnostic reference levels for dental panoramic radiography in Greece.

    PubMed

    Manousaridis, G; Koukorava, C; Hourdakis, C J; Kamenopoulou, V; Yakoumakis, E; Tsiklakis, K

    2015-07-01

    The purpose of the present study was to present the national diagnostic reference levels (DRL) established for panoramic dental examinations in Greece. The establishment of DRL, as a tool for the optimisation of radiological procedures, is a requirement of national regulations. Measurements performed by the Greek Atomic Energy Commission on 90 panoramic systems have been used for the derivation of DRL values. DRL values have been proposed for exposure settings of different patient types (child, small adult and standard adult), both for film and digital imaging. The DRLs for different patient types are grouped in three categories: children, small adults (corresponding to female) and average adults (corresponding to male). Proposed DRLs for these groups are 2.2, 3.3 and 4.1 mGy, respectively. In order to investigate the correlation of DRLs with the available imaging modalities (CR, DR and film), this parameter was taken into account. DR imaging DRL is the lowest at 3.5 mGy, CR imaging the highest at 4.2 mGy and film imaging at 3.7 mGy. In order to facilitate comparison with other studies, kerma-width product values were calculated from Ki, air and field size. PMID:25836684

  9. Radiation absorbed from dental implant radiography: a comparison of linear tomography, CT scan, and panoramic and intra-oral techniques

    SciTech Connect

    Clark, D.E.; Danforth, R.A.; Barnes, R.W.; Burtch, M.L. )

    1990-01-01

    Absorbed radiation dose in bone marrow, thyroid, salivary gland, eye, and skin entrance was determined by placement of lithium fluoride thermoluminescent dosimeters (TLD's) at selected anatomical sites within and on a human-like x-ray phantom. The phantom was exposed to radiation from linear tomographic and computer-assisted tomographic (CT) simulated dental implant radiographic examinations. The mean dose was determined for each anatomical site. Resulting dose measurements from linear tomography and computer-assisted tomography are compared with reported panoramic and intra-oral doses. CT examination delivered the greatest dose, while linear tomography was generally lowest. Panoramic and intra-oral doses were similar to those of linear tomography.

  10. Using GafChromic film to estimate the effective dose from dental cone beam CT and panoramic radiography

    PubMed Central

    Al-Okshi, A; Nilsson, M; Petersson, A; Wiese, M; Lindh, C

    2013-01-01

    Objectives: To demonstrate the feasibility of GafChromic® XR-QA2 (ISP Corp., Wayne, NJ) as a dosemeter when performing measurements of the effective dose from three cone beam CT (CBCT) units and to compare the doses from examinations of three common dental clinical situations. A second aim was to compare the radiation doses for three digital panoramic units with the doses for the CBCT units. Methods: The CBCT units used were Veraviewepocs 3De® (J Morita MFG Corp., Kyoto, Japan), ProMax® 3D (Planmeca, Helsinki, Finland) and NewTom VGi® (Quantitative Radiology, Verona, Italy). GafChromic XR-QA2 films were placed between the selected layers of the head and neck of a tissue-equivalent human skull (RANDO® phantom; The Phantom Laboratory, Salem, NY). The exposure parameters were set using the automatic exposure control function of the units. Depending on the availability, medium and smaller field of view (FOV) scanning modes were used. The effective dose was estimated using the 2007 International Commission on Radiological Protection formalism. Results: The lowest effective dose of a CBCT unit was observed for ProMax 3D, FOV 4 × 5 cm (10 μSv), the highest for NewTom VGi, FOV 8 × 8 cm—high resolution (129 μSv). The range of effective doses for digital panoramic machines measured was 8–14 μSv. Conclusions: This study demonstrates the feasibility of using radiochromic films for dental CBCT and panoramic dosimetry. PMID:23610090

  11. The impact of Platelet Rich Plasma (PRP) in osseointegration of oral implants in dental panoramic radiography: texture based evaluation

    PubMed Central

    Georgakopoulos, Ioannis; Tsantis, Stavros; Georgakopoulos, Panagiotis; Korfiatis, Panagiotis; Fanti, Elena; Martelli, Marialaura; Costaridou, Lena; Petsas, Theodoros; Panayiotakis, George; Martelli, Francesco Saverio

    2014-01-01

    Summary Purpose In this study the temporal texture differentiation associated with the bone formation properties, around loaded oral implants after Platelet Rich Plasma (PRP) employment, was investigated in Panoramic Radiographs. Materials and methods Thirty eligible patients are randomly assigned to two groups. The test group received PRP application around new implants, while in the control group no PRP treatment was made. The bone-to-implant contact region was analyzed in a clinical sample of 60 Digitized Panoramic Radiographs, 30 corresponding to immediate implant loading (Class-I) and 30 after an 8 month follow-up period (Class-II). This region was sampled by 1146 circular Regions-of-Interest (ROIs), resulting from a specifically designed segmentation scheme based on Markov-Random-Fields (MRF). From each ROI, 41 textural features were extracted, then reduced to a subset of 4 features due to redundancy and employed as input to Receiver-Operating-Characteristic (ROC) analysis, to assess the textural differentiation between two classes. Results The selected subset, achieved Area-Under-Curve (AUC) values ranging from 0.77–0.81 in the PRP group, indicating the significant temporal textural differentiation has been made. In the control group, the AUC values ranged from 0.56–0.68 demonstrating lesser osseo integration activity. Conclusion This study provides evidences that PRP application may favor bone formation around loaded dental implants that could modify the dental treatment planning. PMID:25002881

  12. Diagnostic performance of dental students in identifying mandibular condyle fractures by panoramic radiography and the usefulness of reference images

    PubMed Central

    2011-01-01

    Purpose The purpose of this study was to evaluate the diagnostic performance of dental students in detection of mandibular condyle fractures and the effectiveness of reference panoramic images. Materials and Methods Forty-six undergraduates evaluated 25 panoramic radiographs for condylar fractures and the data were analyzed through receiver operating characteristic (ROC) analysis. After a month, they were divided into two homogeneous groups based on the first results and re-evaluated the images with (group A) or without (group B) reference images. Eight reference images included indications showing either typical condylar fractures or anatomic structures which could be confused with fractures. Paired t-test was used for statistical analysis of the difference between the first and the second evaluations for each group, and student's t-test was used between the two groups in the second evaluation. The intra- and inter-observer agreements were evaluated with Kappa statistics. Results Intra- and inter-observer agreements were substantial (k=0.66) and moderate (k=0.53), respectively. The area under the ROC curve (Az) in the first evaluation was 0.802. In the second evaluation, it was increased to 0.823 for group A and 0.814 for group B. The difference between the first and second evaluations for group A was statistically significant (p<0.05), however there was no statistically significant difference between the two groups in the second evaluation. Conclusion Providing reference images to less experienced clinicians would be a good way to improve the diagnostic ability in detecting condylar fracture. PMID:21977475

  13. [Conventional dental radiography and future prospectives].

    PubMed

    Youssefzadeh, S; Gahleitner, A; Bernhart, D; Bernhart, T

    1999-12-01

    Until recently, conventional dental radiology was performed by dentists and orofacial surgeons. Due to the rapid development of radiological technique, the demand of radiological advice is increasing. The radiologists see more and more dental patients in their daily routine. The aim of this article is to give an overview on established dental radiology and a glimpse into the future. Conventional dental radiology and digital radiography are presently in use. Intraoral technique comprises dental films, bite-wing views and occlusal radiographs. Panoramic views and cephalometric radiographs are done with extraoral technique. Digital radiography lacks all processes in behalf of film development. It leads to dose reduction and enables image manipulation. PMID:10643025

  14. [Panoramic radiographs in dental diagnostics].

    PubMed

    van der Stelt, P F

    2016-04-01

    Panoramic radiographs are frequently used in dental practice in addition to bitewing radiographs and periapical radiographs. The way a panoramic photograph is created is different from that of a projection image, such as bitewing and periapical radiographs. As a result, the sharpness of detail is much less, and overlap of structures occurs in different areas of the image. Consequently the diagnostic utility is limited to the recognition of anomalies for which small details play a lesser role. The advantage of a panoramic radiograph is that structures over a large area are shown in their relative location. Because of the lower resolution and the higher dose of radiation to the patient compared with a series of intraoral images, the panoramic radiograph is not indicated during a periodic check-up. If clinical inspection indicates a need for it and as a supplement to an intraoral radiograph, a panoramic radiograph can, however, be appropriate in cases of abnormalities that extend over a larger area, such as tumours and developmental disorders. PMID:27073808

  15. Thyroid dose distribution in dental radiography

    SciTech Connect

    Bristow, R.G.; Wood, R.E.; Clark, G.M. )

    1989-10-01

    The anatomic position and proven radiosensitivity of the thyroid gland make it an organ of concern in dental radiography. A calibrated thermoluminescent dosimetry system was used to investigate the absorbed dose (microGy) to the thyroid gland resultant from a minimum irradiated volume, intraoral full-mouth radiography technique with the use of rectangular collimation with a lead-backed image receptor, and conventional panoramic radiography performed with front and rear lead aprons. Use of the minimum irradiated volume technique resulted in a significantly decreased absorbed dose over the entire thyroid region ranging from 100% to 350% (p less than 0.05). Because this intraoral technique results in radiographs with greater image quality and also exposes the thyroid gland to less radiation than the panoramic, this technique may be an alternative to the panoramic procedure.

  16. Radiation exposure to critical organs in panoramic dental examination.

    PubMed

    Bahreyni Toossi, Mohammad Taghi; Akbari, Fateme; Bayani Roodi, Shahram

    2012-01-01

    Nowadays, radiography is a necessary procedure in diagnosis and treatment of patients with dental problems. According to the ALARA (as low as reasonably achievable) principle, dentists must take radiographs of sufficient quality at the lowest possible radiation dose to the patients. The assessment of patient dose on panoramic radiography is difficult because of dynamic nature of the imaging process and the narrow width of the x-ray beam. The present work describes an experiment undertaken using thermoluminescence dosimeters (TLD-100) to obtain the absorbed dose in organs and sensitive tissues in head and neck region during panoramic radiography, based on patient measurement. The overall mean entrance surface dose on thyroid, right and left lens of eyes, parotid glands (right and left) and occipital region in panoramic were 38, negligible, negligible, 367, 319 and 262 μGy, respectively. The results show that there are differences between patient doses examined by different panoramic systems. There is a tendency for lower organ doses for digital compared with analogue panoramic units. PMID:23456522

  17. Dental digital radiography.

    PubMed

    Moore, William S

    2002-05-01

    Digital images offer tremendous advantages to dentistry in terms of the potential for lower exposure to patients, absence of darkroom or processing problems, convenience of image enhancement techniques and capacity for remote teledentistry. Digital systems are now able to acquire all types of images including panoramic and cephalometric. As technology continues to improve they may ultimately replace film as the medium of choice for dental imaging. PMID:12046403

  18. Proximal caries detection accuracy using intraoral bitewing radiography, extraoral bitewing radiography and panoramic radiography

    PubMed Central

    Kamburoğlu, K; Kolsuz, E; Murat, S; Yüksel, S; Özen, T

    2012-01-01

    Objective To compare proximal caries detection using intraoral bitewing, extraoral bitewing and panoramic radiography. Methods 80 extracted human premolar and molar teeth with and without proximal caries were used. Intraoral radiographs were taken with Kodak Insight film (Eastman Kodak Co., Rochester, NY) using the bitewing technique. Extraoral bitewing and panoramic images were obtained using a Planmeca Promax Digital Panoramic X-ray unit (Planmeca Inc., Helsinki, Finland). Images were evaluated by three observers twice. In total, 160 proximal surfaces were assessed. Intra- and interobserver kappa coefficients were calculated. Scores obtained from the three techniques were compared with the histological gold standard using receiver operating characteristic analysis. Az values for each image type, observer and reading were compared using z-tests, with a significance level of α = 0.05. Results Kappa coefficients ranged from 0.883 to 0.963 for the intraoral bitewing, from 0.715 to 0.893 for the extraoral bitewing, and from 0.659 to 0.884 for the panoramic radiography. Interobserver agreements for the first and second readings for the intraoral bitewing images were between 0.717 and 0.780, the extraoral bitewing readings were between 0.569 and 0.707, and the panoramic images were between 0.477 and 0.740. The Az values for both readings of all three observers were highest for the intraoral bitewing. Az values for the extraoral bitewing images were higher than those of the panoramic images without statistical significance (p > 0.05). Conclusion Intraoral bitewing radiography was superior to extraoral bitewing and panoramic radiography in diagnosing proximal caries of premolar and molar teeth ex vivo. Similar intra- and interobserver coefficients were calculated for extraoral bitewing and panoramic radiography. PMID:22868296

  19. Usefulness of an energy-binned photon-counting x-ray detector for dental panoramic radiographs

    NASA Astrophysics Data System (ADS)

    Fukui, Tatsumasa; Katsumata, Akitoshi; Ogawa, Koichi; Fujiwara, Shuu

    2015-03-01

    A newly developed dental panoramic radiography system is equipped with a photon-counting semiconductor detector. This photon-counting detector acquires transparent X-ray beams by dividing them into several energy bands. We developed a method to identify dental materials in the patient's teeth by means of the X-ray energy analysis of panoramic radiographs. We tested various dental materials including gold alloy, dental amalgam, dental cement, and titanium. The results of this study suggest that X-ray energy scattergram analysis could be used to identify a range of dental materials in a patient's panoramic radiograph.

  20. Shielding effect of thyroid collar for digital panoramic radiography

    PubMed Central

    Han, G-S; Cheng, J-G; Li, G

    2013-01-01

    Objectives: To evaluate the shielding effect of thyroid collar for digital panoramic radiography. Methods: 4 machines [Orthopantomograph® OP200 (Instrumentarium Dental, Tuusula, Finland), Orthophos CD (Sirona Dental Systems GmbH, Bensheim, Germany), Orthophos XG Plus (Sirona Dental Systems GmbH) and ProMax® (Planmeca Oy, Helsinki, Finland)] were used in this study. Average tissue-absorbed doses were measured using thermoluminescent dosemeter chips in an anthropomorphic phantom. Effective organ and total effective doses were derived according to the International Commission of Radiological Protection 2007 recommendations. The shielding effect of one collar in front and two collars both in front and at the back of the neck was measured. Results: The effective organ doses of the thyroid gland obtained from the 4 panoramic machines were 1.12 μSv for OP200, 2.71 μSv for Orthophos CD, 2.18 μSv for Orthophos XG plus and 2.20 μSv for ProMax, when no thyroid collar was used. When 1 collar was used in front of the neck, the effective organ doses of the thyroid gland were 1.01 μSv (9.8% reduction), 2.45 μSv (9.6% reduction), 1.76 μSv (19.3% reduction) and 1.70 μSv (22.7% reduction), respectively. Significant differences in dose reduction were found for Orthophos XG Plus and ProMax. When two collars were used, the effective organ doses of the thyroid gland were also significantly reduced for the two machines Orthophos XG Plus and ProMax. The same trend was observed in the total effective doses for the four machines. Conclusions: Wearing a thyroid collar was helpful when the direct digital panoramic imaging systems were in use, whereas for the indirect digital panoramic imaging systems, the thyroid collar did not have an extra protective effect on the thyroid gland and whole body. PMID:24005060

  1. A review of panoramic radiography and its potential use in implant dentistry.

    PubMed

    Truhlar, R S; Morris, H F; Ochi, S

    Radiographic follow-up of dental implants is one of the most important clinical parameters a practitioner can assess. Recent advances in the design of panoramic radiograph machines have increased their potential use in the longitudinal clinical evaluation of dental implants. Changes from the earliest designs allow for a projection geometry that more closely approximates the shape of the human jaw. The fundamentals of panoramic radiography are reviewed including common errors in patient positioning, their effect on the radiographic image, and how to correct the errors. Comparative advantages and disadvantages of intraoral periapical and bitewing films as compared with panoramic radiographs are discussed, specifically focusing on the amount of radiation exposure, ability to detect bone loss/bone defects, and inherent problems with both systems. PMID:8242015

  2. Common positioning errors in panoramic radiography: A review.

    PubMed

    Rondon, Rafael Henrique Nunes; Pereira, Yamba Carla Lara; do Nascimento, Glauce Crivelaro

    2014-03-01

    Professionals performing radiographic examinations are responsible for maintaining optimal image quality for accurate diagnoses. These professionals must competently execute techniques such as film manipulation and processing to minimize patient exposure to radiation. Improper performance by the professional and/or patient may result in a radiographic image of unsatisfactory quality that can also lead to a misdiagnosis and the development of an inadequate treatment plan. Currently, the most commonly performed extraoral examination is panoramic radiography. The invention of panoramic radiography has resulted in improvements in image quality with decreased exposure to radiation and at a low cost. However, this technique requires careful, accurate positioning of the patient's teeth and surrounding maxillofacial bone structure within the focal trough. Therefore, we reviewed the literature for the most common types of positioning errors in panoramic radiography to suggest the correct techniques. We would also discuss how to determine if the most common positioning errors occurred in panoramic radiography, such as in the positioning of the patient's head, tongue, chin, or body. PMID:24701452

  3. Common positioning errors in panoramic radiography: A review

    PubMed Central

    Rondon, Rafael Henrique Nunes; Pereira, Yamba Carla Lara

    2014-01-01

    Professionals performing radiographic examinations are responsible for maintaining optimal image quality for accurate diagnoses. These professionals must competently execute techniques such as film manipulation and processing to minimize patient exposure to radiation. Improper performance by the professional and/or patient may result in a radiographic image of unsatisfactory quality that can also lead to a misdiagnosis and the development of an inadequate treatment plan. Currently, the most commonly performed extraoral examination is panoramic radiography. The invention of panoramic radiography has resulted in improvements in image quality with decreased exposure to radiation and at a low cost. However, this technique requires careful, accurate positioning of the patient's teeth and surrounding maxillofacial bone structure within the focal trough. Therefore, we reviewed the literature for the most common types of positioning errors in panoramic radiography to suggest the correct techniques. We would also discuss how to determine if the most common positioning errors occurred in panoramic radiography, such as in the positioning of the patient's head, tongue, chin, or body. PMID:24701452

  4. Reduced radiation-absorbed dose to tissues with partial panoramic radiography for evaluation of third molars.

    PubMed

    Kircos, L T; Eakle, W S; Smith, R A

    1986-05-01

    The radiation-absorbed doses from panoramic radiography, distal molar radiography, and a partial panoramic radiographic technique that exposes only the third molar region to radiation are compared. Doses of radiation to the submandibular salivary gland were comparable by all three techniques, but doses of radiation to the head and neck were reduced greatly by the partial panoramic radiographic technique. Partial panoramic radiography is a diagnostically satisfactory and a radiologically safer technique for evaluation of third molar pathosis than is panoramic or distal molar radiography. PMID:3458783

  5. Reduced radiation-absorbed dose to tissues with partial panoramic radiography for evaluation of third molars

    SciTech Connect

    Kircos, L.T.; Eakle, W.S.; Smith, R.A.

    1986-05-01

    The radiation-absorbed doses from panoramic radiography, distal molar radiography, and a partial panoramic radiographic technique that exposes only the third molar region to radiation are compared. Doses of radiation to the submandibular salivary gland were comparable by all three techniques, but doses of radiation to the head and neck were reduced greatly by the partial panoramic radiographic technique. Partial panoramic radiography is a diagnostically satisfactory and a radiologically safer technique for evaluation of third molar pathosis than is panoramic or distal molar radiography.

  6. Accuracy of Digital Bitewing Radiography versus Different Views of Digital Panoramic Radiography for Detection of Proximal Caries

    PubMed Central

    Abdinian, Mehrdad; Razavi, Sayed Mohammad; Samety, Amir Abbas; Faghihian, Elham

    2015-01-01

    Objectives: Dental caries are common and have a high incidence among populations. Radiographs are essential for detecting proximal caries. The best technique should be recognized for accurate detection of caries. The aim of this study was to compare the accuracy of detection of proximal caries using intraoral bitewing, extraoral bitewing, improved interproximal panoramic, improved orthogonality panoramic and conventional panoramic radiographs. Materials and Methods: In this descriptive cross sectional study, 100 extracted human teeth with and without proximal caries were used. Intra and extraoral radiographs were taken. Images were evaluated and scored by two observers. Scores were compared with the histological gold standard. The diagnostic accuracy of radiographs was assessed by means of receiver operating characteristic (ROC) curve analysis (P<0.05). Results: Microscopic evaluation of proximal surfaces revealed that 54.8% of the surfaces were sound and 45.2% were carious (with different depths). The differences in the area under the ROC curve (Az value) among the five techniques were not statistically significant. Conclusion: Improved interproximal panoramic and extraoral bitewing radiographs were superior to conventional panoramic radiography for detection of proximal caries ex vivo and should be considered for patients with contraindications for intraoral radiographs. PMID:26622284

  7. A dose monitoring system for dental radiography

    PubMed Central

    Lee, Chena; Kim, Jo-Eun; Symkhampha, Khanthaly; Lee, Woo-Jin; Huh, Kyung-Hoe; Yi, Won-Jin; Heo, Min-Suk; Choi, Soon-Chul; Yeom, Heon-Young

    2016-01-01

    Purpose The current study investigates the feasibility of a platform for a nationwide dose monitoring system for dental radiography. The essential elements for an unerring system are also assessed. Materials and Methods An intraoral radiographic machine with 14 X-ray generators and five sensors, 45 panoramic radiographic machines, and 23 cone-beam computed tomography (CBCT) models used in Korean dental clinics were surveyed to investigate the type of dose report. A main server for storing the dose data from each radiographic machine was prepared. The dose report transfer pathways from the radiographic machine to the main sever were constructed. An effective dose calculation method was created based on the machine specifications and the exposure parameters of three intraoral radiographic machines, five panoramic radiographic machines, and four CBCTs. A viewing system was developed for both dentists and patients to view the calculated effective dose. Each procedure and the main server were integrated into one system. Results The dose data from each type of radiographic machine was successfully transferred to the main server and converted into an effective dose. The effective dose stored in the main server is automatically connected to a viewing program for dentist and patient access. Conclusion A patient radiation dose monitoring system is feasible for dental clinics. Future research in cooperation with clinicians, industry, and radiologists is needed to ensure format convertibility for an efficient dose monitoring system to monitor unexpected radiation dose. PMID:27358817

  8. [Soft tissue calcifications in panoramic radiography. A risk factor for cerebrovascular accidents?].

    PubMed

    Ariayi, Ayesha Shekeba; Berndt, Dorothea; Lambrecht, J Thomas

    2009-01-01

    Panoramic radiography is a basic diagnostic tool in the dental field where calcifications are seen occasionally in the lateral parts of the x-ray. The differential diagnosis are carotid artery atheromas, calcified submandibular lymphnodes and sialoliths of the submandibular gland. 4007 panoramic radiographs (100%) from patients >40 years were scanned retrospectively. Special emphasis was given to the carotid artery territory (CAT). 225 soft tissue calcifications were found (5.6%). 144 patients had calcifications in the CAT (3.6%), 73 showed calcified submandibular lymphnodes (1.8%), and 8 (0.2%) sialoliths. The female to male ratio was 54.7%:45.3%. Pneumatic diseases were beside hypertension and smoking a risk factor for CAT calcification. Carotid artery atheromas are the main risk for cerebrovascular insults. Dentists can help to detect patients at risk for stroke. Their patients can be referred for further diagnostics (ultrasound). PMID:19954131

  9. Identifying risk groups for osteoporosis by digital panoramic radiography

    PubMed Central

    Alapati, Satish; Reddy, Reddy Sudhakara; Tatapudi, Ramesh; Kotha, Ramya; Bodu, Naveen Kumar; Chennoju, Saikiran

    2015-01-01

    Background: Osteoporosis is a disease characterized by low bone mass and microarchitectural deterioration of bone tissue, leading to bone fragility, and enhanced susceptibility to fractures. Dental radiographs, especially panoramic images, have been used to predict bone mineral density. A number of indices, (mandibular cortical index [MCI], mandibular cortical width [MCW], and panoramic mandibular index [PMI]) have been developed to assess and quantify the quality of mandibular bone mass and to observe the signs of resorption. Objectives: The objectives of the study were to assess mental index (MI), MCW index, and PMI with bone density in identifying risk group for osteoporosis and also to investigate influence of age and gender on MI, MCI, and PMI. Materials and Methods: After obtaining consent, details regarding age, gender, systemic health status, and oral parafunctional habits were recorded in each patient. Then a digital panoramic radiograph was taken. The image thus obtained was subjected to calibrations and morphometric analysis using Digora version 2.7. The obtained values of indices were compared with the mean values of indices, to evaluate subjects whether they are prone to osteoporosis or not. The obtained information was subjected to statistical analysis for the significance of the parameters. Results: Data analysis showed that calibration indices were highly significant in the assessment of risk group for osteoporosis than noncalibration index. The subjects at a higher risk for development of osteoporosis were old-aged adults with higher prevalence being reported in women compared to male subjects. Conclusion: In conclusion, our results suggest that higher percentage of subjects with undetected decreased bone mineral density may be identified based on trained general dental practitioners analyses of their panoramic radiographs using simple screening analytical calibration MI and MCI. PMID:26604582

  10. Optimization of exposure in panoramic radiography while maintaining image quality using adaptive filtering.

    PubMed

    Svenson, Björn; Larsson, Lars; Båth, Magnus

    2016-01-01

    Objective The purpose of the present study was to investigate the potential of using advanced external adaptive image processing for maintaining image quality while reducing exposure in dental panoramic storage phosphor plate (SPP) radiography. Materials and methods Thirty-seven SPP radiographs of a skull phantom were acquired using a Scanora panoramic X-ray machine with various tube load, tube voltage, SPP sensitivity and filtration settings. The radiographs were processed using General Operator Processor (GOP) technology. Fifteen dentists, all within the dental radiology field, compared the structural image quality of each radiograph with a reference image on a 5-point rating scale in a visual grading characteristics (VGC) study. The reference image was acquired with the acquisition parameters commonly used in daily operation (70 kVp, 150 mAs and sensitivity class 200) and processed using the standard process parameters supplied by the modality vendor. Results All GOP-processed images with similar (or higher) dose as the reference image resulted in higher image quality than the reference. All GOP-processed images with similar image quality as the reference image were acquired at a lower dose than the reference. This indicates that the external image processing improved the image quality compared with the standard processing. Regarding acquisition parameters, no strong dependency of the image quality on the radiation quality was seen and the image quality was mainly affected by the dose. Conclusions The present study indicates that advanced external adaptive image processing may be beneficial in panoramic radiography for increasing the image quality of SPP radiographs or for reducing the exposure while maintaining image quality. PMID:26478956

  11. Evaluation of Mental Index, Mandibular Cortical Index and Panoramic Mandibular Index on Dental Panoramic Radiographs in the Elderly

    PubMed Central

    Hastar, Esin; Yilmaz, H. Huseyin; Orhan, Hikmet

    2011-01-01

    Objectives: The aims of this study were to evaluate the influence of gender and dental status on the mental index, mandibular cortical index and panoramic mandibular index from dental panoramic radiographs in elderly who had osteoporosis or did not have osteoporosis. Methods: Panoramic radiographs of 487 elderly dental patients (age range 60–88 years) were evaluated. It were recorded osteoporotic status according to the patients’ medical anamnesis and values of the mandibular cortical index (MCI), panoramic mandibular index (PMI), mandibular cortical width (MCW) Results: Dental status was statistically significantly associated with the mandibular cortical width, panoramic mandibular index and the categories of MCI (P<.05). There were statistically different mandibular cortical width and panoramic mandibular index values in patients with osteoporosis and without osteoporosis (P<.05) Conclusions: Our study showed that there were statistically significant differences according to gender, dental status, and values of the MCW, MCI and PMI between patients with and those without osteoporosis. PMID:21228957

  12. Digital panoramic radiography versus cone beam computed tomography in the delineation of maxillomandibular tumors.

    PubMed

    Almeida-Barros, Renata Quirino de; Abilio, Vanessa Maria Freire; Yamamoto, Angela Toshie Araki; Melo, Daniela Pita de; Godoy, Gustavo Pina; Bento, Patricia Meira

    2015-01-01

    This research aimed to compare the efficacy of digital panoramic radiography (DPR) with that of cone beam computed tomography (CBCT) for delineation of odontogenic and nonodontogenic tumors. From November 2009 through March 2011, 23 tumors in the maxillomandibular complex were diagnosed by histopathological examination. All DPRs and CBCTs were obtained and analyzed by a single previously calibrated radiologist, who considered the following radiographic aspects: clarity of the lesion edges, relation with dental elements, involvement of adjacent anatomical structures, cortical bone expansion and disruption, and, if present, type of involved anatomical structures and site of bone expansion and disruption. Of 23 patients, 15 (65.2%) were male and 8 (34.8%) were female. The tumor was classified as odontogenic in 73.9% of patients and nonodontogenic in 26.1% of patients. Analysis revealed that 56.5% of the tumors were located in the mandible, 34.8% in the maxilla, and 8.7% in both arches. For all analyzed variables, CBCTs offered more accurate details than did DPRs. Panoramic radiography should not be the examination of choice to visualize lesions in the maxillomandibular complex. PMID:26545285

  13. Measurement of the Interantral Bone in Implant Dentistry Using Panoramic Radiography and Cone Beam Computed Tomography: A Human Radiographic Study

    PubMed Central

    Kopecka, D; Simunek, A; Streblov, J; Slezak, R; Capek, L

    2014-01-01

    ABSTRACT Objective: To analyse the dimensions of interantral bone available for dental implant placement in the fully edentulous maxilla. Methods: Interantral bone height (IBH) was measured using panoramic radiography and computed tomography (CT). Interantral bone width (IBW) was measured by means of CT. Results: The difference between both imaging methods in IBH assessment was highly statistically significant (p < 0.001) in the canine area, whereas in other areas, it was found to not be significant. Measured in the CT scans, bone is significantly higher in the canine area compared to the area of central and lateral incisors (p < 0.001). Significant variations in IBW were found in all three locations: bone in the central incisor area is the widest, in the area of the lateral incisor, the narrowest (p < 0.001). Conclusion: Panoramic radiography is a sufficiently accurate method for IBH imaging in the incisor area, but not in the canine area. PMID:25781290

  14. Location of mental foramen using digital panoramic Radiography

    PubMed Central

    Mohamed, Ajmal; Nataraj, Kannan; Mathew, Vinod B.; Varma, Beena; Mohamed, Shamil; Valappila, Nidhin J.; Meena, Aravind S.

    2016-01-01

    Objective: Comparative evaluation of the location of mental foramen in different age groups. Determine the variation in position of mental foramen with gender using digital panoramic radiography. Materials and Methods: Digital panoramic radiographs of 250 patients were reviewed. The study population was divided into five age groups with 50 patients each. Radiographic position of mental foramen was evaluated in each radiograph based on three parameters. Measurements were taken in each radiograph using Planmeca Dimaxis pro version 4.4.0 (Helsinki, Finland). The collected data were subjected to statistical analysis using paired Student's t-test. Results: The mean distance of position of mental foramen showed a significant variation within the five age groups. In the first group, female patients showed an increase in mean distance of mental foramen position in relation to three parameters. From the second to fifth groups, male patient showed an increase in the mean distance of mental foramen position. The first and fifth group showed a reduced mean distance of mental foramen position when compared to other age groups. Conclusion: This study concluded that the position of mental foramen varies with age. There was a gender-related variation in position of mental foramen within the population too. PMID:27555723

  15. Effective doses from panoramic radiography and CBCT (cone beam CT) using dose area product (DAP) in dentistry

    PubMed Central

    Shin, H S; Nam, K C; Park, H; Choi, H U; Kim, H Y

    2014-01-01

    Objectives: We compared the effective dose from panoramic radiography with that from cone beam CT (CBCT) using dose area product under adult and child exposure conditions. Methods: The effective doses of the cephalo, panorama, implant and dental modes of Alphard 3030 (Asahi Roentgen Ind., Co. Ltd, Kyoto, Japan) CBCT and the Jaw, Wide, Facial and temporomandibular joint modes of Rayscan Symphony (RAY Co., Ltd, Hwaseong, Republic of Korea) CBCT were compared with those of CRANEX® 3+ CEPH (Soredex Orion Corporation, Helsinki, Finland) panoramic radiography equipment under adult and child exposure conditions. Each effective dose was calculated using a conversion formula from dose area product meter measured values (VacuTec Messtechnik GmbH, Dresden, Germany). The conversion formulae used were suggested by Helmrot and Alm Carlsson and Batista et al, and they were applied with the tube voltage taken into consideration. Results: The maximum effective doses from the Alphard 3030 and Rayscan Symphony were 67 and 21 times greater than that from panoramic radiography, respectively. The ratios of the effective dose under the child setting to that under the adult condition were 0.60–0.62 and 0.84–0.95, and the maximum differences in effective doses between the adult and child exposure settings were equivalent to 27 and 4 times greater than a panoramic examination in the Alphard 3030 and Rayscan Symphony, respectively. Conclusions: The effective CBCT doses were higher than those of panoramic radiography. The differences in effective doses between the adult and child CBCT settings were dependent on equipment type and exposure parameters. Therefore, adequate mode selection and control of exposure as well as further research are necessary to minimize the effective dose to patients, especially for radiosensitive children. PMID:24845340

  16. Evaluation of Genotoxicity in Patients Subjected to Panoramic Radiography by Micronucleus Assay on Epithelial Cells of the Oral Mucosa

    PubMed Central

    Arora, Pallak; Devi, Parvathi; Wazir, Sartaj Singh

    2014-01-01

    Objective: Radiography is one of the most valuable diagnostic tools used in comprehensive dental care. Although there is no safe level of radiation exposure, the possible risk associated with exposure to radiation, must be elucidated. To date, a variety of assays have been proposed to assess the mutagenic potential of genotoxicants; however, these methods are typically laborious and time consuming. The aim of the present study was to evaluate the possible genotoxic effect of routinely used panoramic radiation exposure in exfoliated epithelial cells as measured by the formation of micronuclei and to compare the genotoxicity of X-rays on keratinized epithelial gingival cells and the nonkeratinized buccal epithelial cells. Materials and Methods: The study included 53 healthy individuals with a mean age of 25.21 ±12.67 years. Specimens of exfoliated epithelial cells were collected from patients subjected to panoramic radiography before and 10 days after radiation exposure. The cells were stained with Giemsa and evaluated for micronuclei by scoring 1000 cells per slide. Results: In our study, the genotoxic effect of radiation exposure from panoramic radiography showed a statistically significant increase in the MN frequency in buccal epithelial cells. A significant correlation was observed between the age of the subjects and micronuclei, although no such correlation was found between gender and micronuclei count. Conclusion: MN test serves as a simple biomarker indicating the direct exposure to DNA damaging agents such as ionizing radiation, emphasizing great sensitivity even for exposure to low doses during radiation screening. Thus, panoramic dental radiography should be cautiously used only when necessary. PMID:24910676

  17. Genotoxic and cytotoxic effects of X-ray on buccal epithelial cells following panoramic radiography: A pediatric study

    PubMed Central

    Agarwal, Poonam; Vinuth, Dhundanalli puttalingaiah; Haranal, Shashidevi; Thippanna, Chandrashekar K.; Naresh, Nitesh; Moger, Ganapathi

    2015-01-01

    Background: Ionizing radiation is a potent mutagenic agent capable of inducing both mutation and chromosomal aberrations. Non-lethal doses of ionizing radiation may induce genomic instability favoring carcinogenesis. In spite of their mutagenic potential, this kind of radiation is an important tool for diagnosis of the disease and is used in medical and dental practice. It has been believed that the number of micronucleus and increased frequency of other nuclear alterations, including karyorrhexis, condensed chromatin and pyknosis, are related to the increasing effects of carcinogens. Many approaches and techniques have been developed for the monitoring of human populations exposed to various mutagens, but the analysis of micronuclei (MN) has become a standard approach for the assessment of chromosomal damage in human populations. Aim: To assess the effects of radiation exposure from panoramic radiography on the buccal epithelial cells (BECs) of pediatric patients. Materials and Methods: The study included 20 pediatric patients who had to undergo panoramic radiography for further dental treatment. Exfoliated BECs were obtained and examined immediately before and 10 days after radiation exposure. The cells were stained using rapid Papanicolaou (PAP) kit. Evaluation for MN and nuclear alterations was carried out by an oral pathologist and data were statistically analyzed using the “t” test. Results: The mean number of MN in the BECs before exposure of pediatric patients to panoramic radiography was 4.25 and after exposure was 4.40. This difference was not found to be statistically significant (P < 0.0001). However, the mean nuclear alterations of 8.70 and 15.75 before and after exposure were statistically significant (P < 0.0001). Conclusion: Panoramic radiographs can induce cytotoxicity but not genotoxic effects in buccal mucosal cells. Hence, dental radiographs should be prescribed only when deemed indispensable. PMID:26229246

  18. Frequency and pattern of idiopathic osteosclerosis and condensing osteitis lesions in panoramic radiography of Iranian patients

    PubMed Central

    Farhadi, Farrokh; Ruhani, Mohammad Razavi; Zarandi, Ali

    2016-01-01

    Background: The purpose of this study was to investigate of radiographic pattern and relative frequency of idiopathic osteosclerosis (IO) and condensing osteitis (CO) in panoramic radiographs. Materials and Methods: Totally 411 panoramic radiographies were randomly selected from patients referred to Radiology Department of Faculty of Dentistry, Tabriz University of Medical Sciences. Descriptive characteristics of radiopacities, including shape, border, localization, and dental relationship, were recorded. The Chi-squared test was used. Results: IO was detected in 31 (7.5%) patients and 22 (68.8%) lesions had exact border while their shape was mostly irregular. About 17 (53.1%) lesions were apical, and 13 (40.6%) lesions had no relation to the teeth. The most involved teeth were the second premolar (28.1%) and first molar (25%). Moreover, CO was detected in 32 (7.8%) patients. 17 (53.1%) lesions had an ill-defined border, and their shape was mostly irregular (65.6%) with ill-defined border. Around 18 (56.3%) lesions were apical, and 11 (34.4) lesions were apical and interradicular. The most involved teeth were the second premolar (59.4%) and the first molar (21.9%). Conclusion: The results demonstrated that relative frequency of IO in the selected population was 7.5% and for CO, it was 7.8%.

  19. The reduction of dose in paediatric panoramic radiography: the impact of collimator height and programme selection

    PubMed Central

    Safi, H; Maddison, S M

    2015-01-01

    Objectives: The aim of this work was to estimate the doses to radiosensitive organs in the head of a young child undergoing panoramic radiography and to establish the effectiveness of a short collimator in reducing dose. Methods: Thermoluminescent dosemeters were used in a paediatric head phantom to simulate an examination on a 5-year-old child. The panoramic system used was an Instrumentarium OP200 D (Instrumentarium Dental, Tuusula, Finland). The collimator height options were 110 and 140 mm. Organ doses were measured using exposure programmes intended for use with adult and child size heads. The performance of the automatic exposure control (AEC) system was also assessed. Results: The short collimator reduced the dose to the brain and the eyes by 57% and 41%, respectively. The dose to the submandibular and sublingual glands increased by 32% and 20%, respectively, when using a programme with a narrower focal trough intended for a small jaw. The effective dose measured with the short collimator and paediatric programme was 7.7 μSv. The dose to the lens of the eye was 17 μGy. When used, the AEC system produced some asymmetry in the dose distribution across the head. Conclusions: Panoramic systems when used to frequently image children should have programmes specifically designed for imaging small heads. There should be a shorter collimator available and programmes that deliver a reduced exposure time and allow reduction of tube current. Programme selection should also provide flexibility for focal trough size, shape and position to match the smaller head size. PMID:25352427

  20. Panoramic and cephalometric extraoral dental radiograph systems.

    PubMed

    2002-12-01

    The basic unit is the Orthopantomograph OP100, which is a computer-controlled extraoral imaging system capable of producing panoramic radiographs using either film or digital technology. This unit has automatic exposure control, automatic spine compensation, a patented V-shaped X-ray beam and a built-in quality assurance program. The OP100 is available with cephalometrics (the OC100 model), linear tomography (the Ortho Trans model), identification film marking (the Ortho ID model) and imaging software (the Ortho Zone and Ortho TMJ models). The addition of a cephalometric arm to the Orthopantomograph makes the unit an Orthoceph. The image receptor sizes are as follows: Panorama OP100: cassette 15 x 30 centimeters; Cephalometric image receptor OC100: 24 x 30 cm, 18 x 24 cm, 8 x 10 inches; Panoramic image receptor OP100D: CCD camera, image pixel size 90 x 90 micrometers; Cephalometric image receptor OC100D: CCD camera, image pixel size 90 x 90 microm. PMID:12512672

  1. Radiation-absorbed doses and energy imparted from panoramic tomography, cephalometric radiography, and occlusal film radiography in children

    SciTech Connect

    Bankvall, G.; Hakansson, H.A.

    1982-05-01

    The absorbed doses and energy imparted from radiographic examinations of children, using panoramic tomography (PTG), cephalometric radiography (CPR), and maxillary frontal occlusal overview (FOO), were examined. The absorbed dose at various sites of the head were measured with TL dosimeters in a phantom and in patients. The energy imparted was calculated from measurements of areal exposure using a planparallel ionization chamber. The maximum absorbed doses for panoramic tomography were located around the lateral rotation center, for cephalometric radiography in the left (tube side) parotid region, and for frontal occlusal radiography in the nose. The absorbed doses in the eyes, thyroid gland, and skin are discussed and compared with previous reports and, for the most part, are found to be in agreement. The mean energy imparted from all three examination methods is 5 mJ with about 57 percent from panoramic, 33 percent from cephalometric, and 10 percent from frontal occlusal examinations. The energy imparted from cephalometric radiography can be reduced to about 10 percent with the use of an improved examination technique, leaving panoramic tomography responsible for contributing about 80 percent of the total energy imparted.

  2. Problems associated with veterinary dental radiography.

    PubMed

    Eisner, E R

    1990-03-01

    Veterinarians have been radiographing animal skulls for many years, but sophisticated dentistry was not widely used until the 1970s. Elevated awareness of veterinary dental techniques has led to the need for producing accurate radiographic images of the teeth and periodontal structures. Many problems arise for the clinician who treats small animals who has, before this time, radiographed the skull of dogs and cats solely for the purpose of assessing neoplastic, infectious, or traumatic disease of the mandible, maxilla, or calvarium and now desires to perform dental radiography. This chapter will describe the advantages and disadvantages of some of the more common types of radiographic equipment and supplies, discuss extraoral and intraoral radiographic positioning and technique, identify anatomic landmarks and diagnostic features of intraoral radiography, and offer suggestions concerning the art of using dental radiography in veterinary practice. PMID:2134590

  3. Diagnostic reference levels for panoramic and lateral cephalometric radiography of Korean children.

    PubMed

    Kim, Young-Hee; Yang, Byoung-Eun; Yoon, Suk-Ja; Kang, Byung-Cheol; Lee, Jae-Seo

    2014-08-01

    Pediatric patients are considered to be more radiosensitive than adults; thus, radiation dose evaluations based on radiologic examinations are particularly important in this population. However, no national diagnostic reference levels (DRLs) are available for pediatric patients in the Republic of Korea. Therefore, the aim of this study was to determine the usage of panoramic and cephalometric radiography under the National Health Insurance (NHI) scheme and to investigate the current DRLs for child panoramic and lateral cephalometric radiography using dose area product (DAP). DAP values were obtained for standard child exposure settings used routinely by dentists. Analysis was performed on data obtained from 28 panoramic and 20 cephalometric x-ray units for the DAP investigation. DRLs for child panoramic and cephalometric radiography were found to be 95.9 mGy cm and 121.3 mGy cm, respectively. These DRLs are higher than those recommended in the UK and Germany, which indicates that further effort is required to reduce pediatric doses in the Republic of Korea. PMID:24978282

  4. Infection control practices for dental radiography.

    PubMed

    Palenik, Charles John

    2004-06-01

    Infection control for dental radiography employs the same materials, processes, and techniques used in the operatory, yet unless proper procedures are established and followed, there is a definite potential for cross-contamination to clinical area surfaces and DHCP. In general, the aseptic practices used are relatively simple and inexpensive, yet they require complete application in every situation. PMID:15218669

  5. Magnification rate of digital panoramic radiographs and its effectiveness for pre-operative assessment of dental implants

    PubMed Central

    Kim, Y-K; Park, J-Y; Kim, S-G; Kim, J-S; Kim, J-D

    2011-01-01

    Objectives The purpose of this study was to determine the accuracy and effectiveness of digital panoramic radiographs for pre-operative assessment of dental implants. Methods We selected 86 patients (221 implants) and calculated the length of the planned implant based on the distance between a selection of critical anatomical structures and the alveolar crest using the scaling tools provided in the digital panoramic system. We analysed the magnification rate and the difference between the actual inserted implant length and planned implant length according to the location of the implant placement and the clarity of anatomical structures seen in the panoramic radiographs. Results There was no significant difference between the planned implant length and actual inserted implant length (P > 0.05). The magnification rate of the width and length of the inserted implants, seen in the digital panoramic radiographs, was 127.28 ± 13.47% and 128.22 ± 4.17%, respectively. The magnification rate of the implant width was largest in the mandibular anterior part and there was a significant difference in the magnification rate of the length of implants between the maxilla and the mandible (P < 0.05). When the clarity of anatomical structures seen in the panoramic radiographs is low, the magnification rate of the width of the inserted implants is significantly higher (P < 0.05), but there is no significant difference between the planned implant length and actual inserted implant length according to the clarity of anatomical structures (P < 0.05). Conclusions Digital panoramic radiography can be considered a simple, readily available and considerably accurate pre-operative assessment tool in the vertical dimension for dental implant therapy. PMID:21239569

  6. 42 CFR Appendix G to Part 75 - Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography G Appendix G to Part 75 Public Health PUBLIC HEALTH SERVICE...—Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography The following...

  7. 42 CFR Appendix G to Part 75 - Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography G Appendix G to Part 75 Public Health PUBLIC HEALTH SERVICE...—Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography The following...

  8. 42 CFR Appendix G to Part 75 - Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography G Appendix G to Part 75 Public Health PUBLIC HEALTH SERVICE...—Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography The following...

  9. 42 CFR Appendix G to Part 75 - Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography G Appendix G to Part 75 Public Health PUBLIC HEALTH SERVICE...—Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography The following...

  10. 42 CFR Appendix G to Part 75 - Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography G Appendix G to Part 75 Public Health PUBLIC HEALTH SERVICE...—Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography The following...

  11. Dental panoramic image analysis for enhancement biomarker of mandibular condyle for osteoporosis early detection

    NASA Astrophysics Data System (ADS)

    Suprijanto; Azhari; Juliastuti, E.; Septyvergy, A.; Setyagar, N. P. P.

    2016-03-01

    Osteoporosis is a degenerative disease characterized by low Bone Mineral Density (BMD). Currently, a BMD level is determined by Dual Energy X-ray Absorptiometry (DXA) at the lumbar vertebrae and femur. Previous studies reported that dental panoramic radiography image has potential information for early osteoporosis detection. This work reported alternative scheme, that consists of the determination of the Region of Interest (ROI) the condyle mandibular in the image as biomarker and feature extraction from ROI and classification of bone conditions. The minimum value of intensity in the cavity area is used to compensate an offset on the ROI. For feature extraction, the fraction of intensity values in the ROI that represent high bone density and the ROI total area is perfomed. The classification will be evaluated from the ability of each feature and its combinations for the BMD detection in 2 classes (normal and abnormal), with the artificial neural network method. The evaluation system used 105 panoramic image data from menopause women which consist of 36 training data and 69 test data that were divided into 2 classes. The 2 classes of classification obtained 88.0% accuracy rate and 88.0% sensitivity rate.

  12. Alteration of computer dental radiography images.

    PubMed

    Bruder, G A; Casale, J; Goren, A; Friedman, S

    1999-04-01

    This study was designed to determine if digital images stored on the hard drive of a Schick computer dental radiography system could be exported, altered, and then restored to the drive without any visible signs of alteration. Digital images were downloaded from the computer dental radiography system using an I-Omega Zip Drive, 100-MB capacity, and then opened in Corel Photo Paint where images were altered and manufacturer export symbols were edited. The resulting images were printed to a default printer (Fargo Foto Fun). The ease of manipulation of the exported digital images reflects the need for the manufacturer to implement safeguards so that the integrity of digital imaging cannot be compromised. Computer dental radiography has many advantages: conservation of time (instant radiographs), less radiation (50 to 60%), no chemical waste, and many viewing options. However, questions that might be raised regarding the ability of persons with minimal computer expertise, using a commercially available program to alter images should be addressed. PMID:10425956

  13. The integral dose in panoramic intraoral x-ray tube radiography

    SciTech Connect

    Hayami, A.; Fujishita, M.; Sumida, A.; Kanke, M.; Fujiki, T.; Uemura, S.; Fuchihata, H.

    1983-07-01

    A Monte Carlo computer program was developed to estimate the integral dose to the head and thyroid for panoramic intraoral x-ray tube radiography. The advantage of this computer simulation is that it is able to avoid many of the difficulties associated with low-energy and low-dose x-ray dosimetry. The calculations were made for maxillary and mandibular projections separately, using 10 kv. increments between 40 and 60 kv. The results obtained were presented in terms of the integral dose per milliampere second. Typical integral doses for a routine examination of the head are 2.1 mJ. and 8.5 microJ for the thyroid during mandibular radiography and 1.7 microJ for the thyroid during radiography of the maxilla using 55 kv. and 0.5 mAs.

  14. Development of a digital panoramic X-ray imaging system of adaptive image layers for dental applications

    NASA Astrophysics Data System (ADS)

    Choi, S. I.; Park, Y. O.; Cho, H. S.; Oh, J. E.; Cho, H. M.; Hong, D. K.; Lee, M. S.; Yang, Y. J.; Je, U. K.; Kim, D. S.; Lee, H. K.

    2011-10-01

    As a continuation of our digital radiographic sensor R&D, we have developed a prototyped digital panoramic X-ray imaging system for dental applications. The imaging system consists of a slit-collimated X-ray generator with a 0.4 mm focal spot size and a 3.5 mm Al filtration, a linear-array typed CMOS imager with a 48×48 μm 2 pixel size and a 128 (in the scan direction)×3072 (in the vertical direction) pixel format, a series of microstep motors for the precise motion control of the imaging system, and the designed sequences for the motion control and pixel readout required to make a specific plane of interest (POI) to be focused. With the several test phantoms we designed, we obtained useful digital panoramic X-ray images by moving the X-ray generator and the CMOS imager along a continuously sliding rotational center. In this study, we demonstrated that the prototype system can be applicable to any shaped POI or multi-POIs simultaneously to be focused, provided that adequate sequences for motion control and pixel readout are designed. We expect that the imaging system will be useful for our ongoing applications of dental panoramic radiography and nondestructive testing.

  15. Evaluation of diagnostic accuracy of conventional and digital periapical radiography, panoramic radiography, and cone-beam computed tomography in the assessment of alveolar bone loss

    PubMed Central

    Takeshita, Wilton Mitsunari; Vessoni Iwaki, Lilian Cristina; Da Silva, Mariliani Chicarelli; Tonin, Renata Hernandes

    2014-01-01

    Background: To evaluate the diagnostic accuracy of different radiographic methods in the assessment of proximal alveolar bone loss (ABL). Materials and Methods: ABL, the distance between cement-enamel junction and alveolar bone crest, was measured in 70 mandibular human teeth – directly on the mandibles (control), using conventional periapical radiography with film holders (Rinn XCP and Han-Shin), digital periapical radiography with complementary metal-oxide semiconductor sensor, conventional panoramic, and cone-beam computed tomography (CBCT). Three programs were used to measure ABL on the images: Image tool 3.0 (University of Texas Health Sciences Center, San Antonio, Texas, USA), Kodak Imaging 6.1 (Kodak Dental Imaging 6.1, Carestream Health®, Rochester, NY, USA), and i-CAT vision 1.6.20. Statistical analysis used ANOVA and Tukey's test at 5% significance level. Results: The tomographic images showed the highest means, whereas the lowest were found for periapical with Han-Shin. Controls differed from periapical with Han-Shin (P < 0.0001). CBCT differed from panoramic (P = 0.0130), periapical with Rinn XCP (P = 0.0066), periapical with Han-Shin (P < 0.0001), and digital periapical (P = 0.0027). Conventional periapicals with film holders differed from each other (P = 0.0007). Digital periapical differed from conventional periapical with Han-Shin (P = 0.0004). Conclusions: Conventional periapical with Han-Shin film holder was the only method that differed from the controls. CBCT had the closest means to the controls. PMID:25191066

  16. Comparison between DICOM-calibrated and uncalibrated consumer grade and 6-MP displays under different lighting conditions in panoramic radiography

    PubMed Central

    Haapea, M; Liukkonen, E; Huumonen, S; Tervonen, O; Nieminen, M T

    2015-01-01

    Objectives: To compare observer performance in the detection of anatomical structures and pathology in panoramic radiographs using consumer grade with and without digital imaging and communication in medicine (DICOM)-calibration and 6-megapixel (6-MP) displays under different lighting conditions. Methods: 30 panoramic radiographs were randomly evaluated on three displays under bright (510 lx) and dim (16 lx) ambient lighting by two observers with different years of experience. Dentinoenamel junction, dentinal caries and periapical inflammatory lesions, visibility of cortical border of the floor and pathological lesions in maxillary sinus were evaluated. Consensus between the observers was considered as reference. Intraobserver agreement was determined. Proportion of equivalent ratings and weighted kappa were used to assess reliability. The level of significance was set to p < 0.05. Results: The proportion of equivalent ratings with consensus differed between uncalibrated and DICOM-calibrated consumer grade displays in dentinal caries in the lower molar in dim lighting (p = 0.021) and between DICOM-calibrated consumer grade and 6-MP display in bright lighting (p = 0.038) for an experienced observer. Significant differences were found between uncalibrated and DICOM-calibrated consumer grade displays in dentinal caries in bright lighting (p = 0.044) and periapical lesions in the upper molar in dim lighting (p = 0.008) for a less experienced observer. Intraobserver reliability was better at detecting dentinal caries than at detecting periapical and maxillary sinus pathology. Conclusions: DICOM calibration may improve observer performance in panoramic radiography in different lighting conditions. Therefore, a DICOM-calibrated consumer grade display can be used instead of a medical display in dental practice without compromising the diagnostic quality. PMID:25564888

  17. Diagnosis of simulated condylar bone defects using panoramic radiography, spiral tomography and cone-beam computed tomography: A comparison study

    PubMed Central

    Salemi, Fatemeh; Shokri, Abbas; Baharvand, Maryam

    2015-01-01

    Objectives: Radiographic examination is one of the most important parts of the clinical assessment routine for temporomandibular disorders. The aim of this study was to compare the diagnostic accuracy of cone-beam computed tomography(CBCT) with panoramic radiography and spiral computed tomography for the detection of the simulated mandibular condyle bone lesions. Study Design: The sample consisted of 10 TMJs from 5 dried human skulls. Simulated erosive and osteophytic lesions were created in 3 different sizes using round diamond bur and bone chips, respectively. Panoramic radiography, spiral tomography and cone-beam computed tomography were used in defect detection. Data were statistically analyzed with the Mann-Whitney test. The reliability and degrees of agreement between two observers were also determined by the mean of Cohen’s Kappa analysis. Results: CBCT had a statistically significant superiority than other studied techniques in detection of both erosive and osteophytic lesions with different sizes. There were significant differences between tomography and panoramic in correct detection of both erosive and osteophytic lesions with 1mm and 1.5 mm in size. However, there were no significant differences between Tomography and Panoramic in correct detection of both erosive and osteophytic lesions with 0.5 mm in size. Conclusions: CBCT images provide a greater diagnostic accuracy than spiral tomography and panoramic radiography in the detection of condylar bone erosions and osteophytes. Key words:Bone defect, Condyle, CBCT, Panoramic, radiography. PMID:25810839

  18. Influence of lead apron shielding on absorbed doses from panoramic radiography

    PubMed Central

    Rottke, D; Grossekettler, L; Sawada, K; Poxleitner, P; Schulze, D

    2013-01-01

    Objectives: This study investigated the absorbed doses in a full anthropomorphic body phantom from two different panoramic radiography devices, performing protocols with and without applying a lead apron. Methods: A RANDO® full body phantom (Alderson Research Laboratories Inc., Stamford, CT) was equipped with 110 thermoluminescent dosemeters at 55 different sites and set up in two different panoramic radiography devices [SCANORA® three-dimensional (3D) (SOREDEX, Tuusula, Finland) and ProMax® 3D (Planmeca, Helsinki, Finland)] and exposed. Two different protocols were performed in the two devices. The first protocol was performed without any lead shielding, whereas the phantom was equipped with a standard adult lead apron for the second protocol. Results: A two-tailed paired samples t-test for the SCANORA 3D revealed that there is no difference between the protocol using lead apron shielding (m = 87.99, s = 102.98) and the protocol without shielding (m = 87.34, s = 107.49), t(54) = −0.313, p > 0.05. The same test for the ProMax 3D showed that there is also no difference between the protocol using shielding (m = 106.48, s = 117.38) and the protocol without shielding (m = 107.75, s = 114,36), t(54) = 0.938, p > 0.05. Conclusions: In conclusion, the results of this study showed no statistically significant differences between a panoramic radiography with or without the use of lead apron shielding. PMID:24174012

  19. Relationship Between Carotid Artery Calcification Detected in Dental Panoramic Images and Hypertension and Myocardial Infarction

    PubMed Central

    Moshfeghi, Mahkameh; Taheri, Jamileh Beigom; Bahemmat, Nika; Evazzadeh, Mohammad Ebrahim; Hadian, Hoora

    2014-01-01

    Background: Carotid artery calcification may be related to cerebrovascular accident, which may result in death or physical and mental disabilities in survivors. Objectives: Our purpose is to study the association of carotid artery calcification (CAC) on dental panoramic radiographs and two risk factors of cerebrovascular accident (CVA) including hypertension and myocardial infarction (MI). Patients and Methods: Panoramic images of 200 patients that were all women above 50 years of age (a population suffering from vascular diseases) were investigated. All panoramic images were provided under similar conditions in terms of the type of panoramic radiograph equipment, type of applied films and the automatic film processor. Then, the patients answered questions about MI history and taking antihypertensive drugs. We also measured the blood pressure of patients in two separate surveys. Data analysis was performed by SPSS statistical program. We used Exact Fisher test and Chi-Square test at a significant level of less than 0.05 to study the effect of these variables on the occurrence of carotid artery calcification. Results: Among 200 studied samples, 22 of the patients (11%) had carotid artery calcification on the dental panoramic radiograph. In total, 52 patients (26%) had hypertension and four people (2%) had a history of MI. Eleven individuals among patients suffering from hypertension (21.2%) and three individuals among patients with a history of MI (75%) demonstrated CAC on dental panoramic images . Conclusions: The relationship between CAC found on dental panoramic radiographs and two CVA risk factors--hypertension and MI-- was significant. Therefore, it seems that detection of CAC on panoramic images of dental patients must be considered by dentists. PMID:25763086

  20. Assessment of maxillary third molars with panoramic radiography and cone-beam computed tomography

    PubMed Central

    Jung, Yun-Hoa

    2015-01-01

    Purpose This study investigated maxillary third molars and their relation to the maxillary sinus using panoramic radiography and cone-beam computed tomography (CBCT). Materials and Methods A total of 395 maxillary third molars in 234 patients were examined using panoramic radiographs and CBCT images. We examined the eruption level of the maxillary third molars, the available retromolar space, the angulation, the relationship to the second molars, the number of roots, and the relationship between the roots and the sinus. Results Females had a higher frequency of maxillary third molars with occlusal planes apical to the cervical line of the second molar (Level C) than males. All third molars with insufficient retromolar space were Level C. The most common angulation was vertical, followed by buccoangular. Almost all of the Level C molars were in contact with the roots of the second molar. Erupted teeth most commonly had three roots, and completely impacted teeth most commonly had one root. The superimposition of one third of the root and the sinus floor was most commonly associated with the sinus floor being located on the buccal side of the root. Conclusion Eruption levels were differently distributed according to gender. A statistically significant association was found between the eruption level and the available retromolar space. When panoramic radiographs showed a superimposition of the roots and the sinus floor, expansion of the sinus to the buccal side of the root was generally observed in CBCT images. PMID:26730371

  1. Residual bone height measured by panoramic radiography in older edentulous Korean patients

    PubMed Central

    Liang, Xiang Hua; Kim, Young-Mi

    2014-01-01

    PURPOSE The aim of this study was to obtain statistical data on the residual bone height at different natural tooth positions by panoramic radiography in edentulous Korean patients aged 60-90 years. MATERIALS AND METHODS The study included the diagnostic panoramic radiographs of 180 randomly selected edentulous patients without systemic diseases affecting bone. The radiographic selection criteria included absence of obvious facial asymmetry, clearly visible anatomic structures, and no surgical and fracture history. The panoramic radiographs of 79 patients met these criteria and were used in the analysis. The same researcher processed all the radiographs by using a standardized method. The height of the residual bone was measured at 18 predetermined sites (7 in the maxilla and 11 in the mandible) on digitized and printed radiographs by using a Digimatic caliper, triangle, and ruler. Gender- and age-related differences were statistically analyzed by using the t-test and rank-sum test (α=0.05). RESULTS The maxillary residual bone height did not show significant gender-related differences, but male patients had significantly higher residual bone in the mandible(P<.05). No significant height differences at the measured sites were noted among the 60s, 70s, and 80s age groups. CONCLUSION Dentists should pay greater attention to older female edentulous patients because they are more prone to rapid residual bone resorption. Residual bone resorption may not be affected by age. PMID:24605207

  2. Effects of dose reduction on the detectability of standardized radiolucent lesions in digital panoramic radiography.

    PubMed

    Dula, K; Sanderink, G; van der Stelt, P F; Mini, R; Buser, D

    1998-08-01

    Dose reduction in digital panoramic radiography was studied. Intentional underexposure was performed with the Orthophos DS while six different human mandibles were radiographed. Exposure settings were 69 kV/15 mA (standard), 64 kV/16 mA, and 60 kV/16 mA. Standardized spherical defects, each either 1 or 1.25 mm in diameter, were simulated in 288 of 432 images, and seven observers decided whether defects were present or not. Areas under the receiver operating characteristics curves were calculated. They showed no significant differences in the detectability of the 1-mm defect at 69, 64, or 60 kV. For the 1.25-mm defect, no difference was found between the 69 and 60 kV images, but a statistically significant different detectability was found for 64 kV images in comparison with both 69 and 60 kV images. A dose reduction of up to 43% was ascertained with a Pedo-RT-Humanoid phantom when panoramic radiography was performed at 60 kV/16 mA. The conclusion is that with the Orthophos DS, it seems possible to reduce the dose rate of x-rays without loss of diagnostic quality in the case of radiolucent changes. PMID:9720100

  3. Automatic Synthesis of Panoramic Radiographs from Dental Cone Beam Computed Tomography Data.

    PubMed

    Luo, Ting; Shi, Changrong; Zhao, Xing; Zhao, Yunsong; Xu, Jinqiu

    2016-01-01

    In this paper, we propose an automatic method of synthesizing panoramic radiographs from dental cone beam computed tomography (CBCT) data for directly observing the whole dentition without the superimposition of other structures. This method consists of three major steps. First, the dental arch curve is generated from the maximum intensity projection (MIP) of 3D CBCT data. Then, based on this curve, the long axial curves of the upper and lower teeth are extracted to create a 3D panoramic curved surface describing the whole dentition. Finally, the panoramic radiograph is synthesized by developing this 3D surface. Both open-bite shaped and closed-bite shaped dental CBCT datasets were applied in this study, and the resulting images were analyzed to evaluate the effectiveness of this method. With the proposed method, a single-slice panoramic radiograph can clearly and completely show the whole dentition without the blur and superimposition of other dental structures. Moreover, thickened panoramic radiographs can also be synthesized with increased slice thickness to show more features, such as the mandibular nerve canal. One feature of the proposed method is that it is automatically performed without human intervention. Another feature of the proposed method is that it requires thinner panoramic radiographs to show the whole dentition than those produced by other existing methods, which contributes to the clarity of the anatomical structures, including the enamel, dentine and pulp. In addition, this method can rapidly process common dental CBCT data. The speed and image quality of this method make it an attractive option for observing the whole dentition in a clinical setting. PMID:27300554

  4. Automatic Synthesis of Panoramic Radiographs from Dental Cone Beam Computed Tomography Data

    PubMed Central

    Luo, Ting; Shi, Changrong; Zhao, Xing; Zhao, Yunsong; Xu, Jinqiu

    2016-01-01

    In this paper, we propose an automatic method of synthesizing panoramic radiographs from dental cone beam computed tomography (CBCT) data for directly observing the whole dentition without the superimposition of other structures. This method consists of three major steps. First, the dental arch curve is generated from the maximum intensity projection (MIP) of 3D CBCT data. Then, based on this curve, the long axial curves of the upper and lower teeth are extracted to create a 3D panoramic curved surface describing the whole dentition. Finally, the panoramic radiograph is synthesized by developing this 3D surface. Both open-bite shaped and closed-bite shaped dental CBCT datasets were applied in this study, and the resulting images were analyzed to evaluate the effectiveness of this method. With the proposed method, a single-slice panoramic radiograph can clearly and completely show the whole dentition without the blur and superimposition of other dental structures. Moreover, thickened panoramic radiographs can also be synthesized with increased slice thickness to show more features, such as the mandibular nerve canal. One feature of the proposed method is that it is automatically performed without human intervention. Another feature of the proposed method is that it requires thinner panoramic radiographs to show the whole dentition than those produced by other existing methods, which contributes to the clarity of the anatomical structures, including the enamel, dentine and pulp. In addition, this method can rapidly process common dental CBCT data. The speed and image quality of this method make it an attractive option for observing the whole dentition in a clinical setting. PMID:27300554

  5. Panoramic Radiography in the Diagnosis of Carotid Artery Atheromas and the Associated Risk Factors

    PubMed Central

    Guimarães Henriques, João César; Kreich, Eliane Maria; Helena Baldani, Márcia; Luciano, Mariely; Cezar de Melo Castilho, Julio; Cesar de Moraes, Luiz

    2011-01-01

    Atherosclerosis is a serious chronic disease, responsible for thousands of deaths worldwide and is characterized by thickening and loss of elasticity of the arterial walls, associated with the presence of atheromatous plaques. Various risk factors act directly on predisposition to the disease, among which the following are pointed out: diabetes mellitus, arterial hypertension and inadequate diet and eating habits. More recent researches have elucidated new risk factors acting in the development of this disease, such as, for example: periodontitis, chronic renal disease and menopause. The panoramic radiograph, commonly used in dental practice, makes it possible to see calcified atherosclerotic plaques that are eventually deposited in the carotid arteries. The aim of this review article was to emphasize the dentist’s important role in the detection of carotid artery atheromas in panoramic radiographs and the immediate referral of patients affected by these calcifications to doctors. In addition, the study intended to guide the dentist, especially the dental radiologist, with regard to differential diagnosis, which should be made taking into consideration particularly the triticeal cartilage when it is calcified. PMID:21760860

  6. Prevalence of dental anomalies among 7- to 35-year-old people in Hamadan, Iran in 2012-2013 as observed using panoramic radiographs

    PubMed Central

    Shokri, Abbas; Khajeh, Samira; Faramarzi, Farhad; Kahnamoui, Hanieh Mogaver

    2014-01-01

    Purpose This study was performed to evaluate the prevalence of all types and subtypes of dental anomalies among 7- to 35-year-old patients by using panoramic radiographs. Materials and Methods This cross-sectional study was conducted on 1649 people in Hamadan City, in 2012-2013. The prevalence of four types and 12 subtypes of dental anomalies was evaluated by two observers separately by using panoramic radiography. Dental anomalies were divided into four types: (a) shape (including fusion, taurodontism, and dens invagination); (b) number (including hypodontia, oligodontia, and hyperdontia); (c) structure (including amelogenesis imperfecta, dentinogenesis imperfecta, and dentin dysplasia); and (d) position (including displacement, impaction, and dilacerations). Results The reliability between the two observers was 79.56% according to the Kappa statistics. The prevalence of dental anomalies diagnosed by panoramic radiographs was 29%. Anomalies of position and number were the most common types of abnormalities, and anomalies of shape and structure were the least in both genders. Anomalies of impaction (44.76%), dilacerations (21.11%), hypodontia (15.88%), taurodontism (9.29%), and hyperdontia (6.76%) were the most common subtypes of dental anomalies. The anomalies of shape and number were more common in the age groups of 7-12 years and 13-15 years, respectively, while the anomalies of structure and position were more common among the other age groups. Conclusion Anomalies of tooth position were the most common type of dental anomalies, and structure anomalies were the least in this Iranian population. The frequency and type of dental anomalies vary within and between populations, confirming the role of racial factors in the prevalence of dental anomalies. PMID:24701453

  7. The prevalence of foreign bodies in jaw bones on panoramic radiography

    PubMed Central

    Omezli, Mehmet Melih; Torul, Damla; Sivrikaya, Efe Can

    2015-01-01

    Objective: Foreign bodies can be deposited in the oral cavity either by traumatic or iatrogenic injury. The most common foreign bodies of iatrogenic origin encountered are restorative materials, like amalgam, and root canal fillings. The aim of this study was to determine the prevalence of foreign bodies detected with panoramic radiography in the jawbones, as well as to evaluate the etiology and characteristics of these pathologies. Materials and Methods: From March 2012 to January 2014, 11,144 panoramic radiographs were taken and retrospectively reviewed. The number, characteristics, location of the foreign bodies, age, and gender of the patients were recorded. Results: Of the 11,144 patients reviewed, 62 of them have a foreign body with a frequency of 0.6%. The patients who had a foreign body were between 14 and 81 years old. Female patients showed more foreign bodies than male patients. Among the 62 patients, 63 filling materials, one stapler, and five shrapnel were detected. Only 8 patients had symptoms associated with foreign bodies and these foreign bodies excised surgically. Conclusion: If possible, these pathologies must be removed at the time of detection to prevent further complications; however, in asymptomatic cases, according to location and the characteristic of the foreign body, they can be kept under observation without performing any operations. PMID:26752878

  8. Root-Crown Ratio in Permanent Dentition Using Panoramic Radiography in a Selected Iranian Population

    PubMed Central

    Haghanifar, Sina; Moudi, Ehsan; Abbasi, Shirin; Bijani, Ali; Poorsattar Bejeh Mir, Arash; Ghasemi, Nafiseh

    2014-01-01

    Statement of the Problem: Determining the crown-root ratio is crucial in many dental clinical decisions. There are no reliable data presented for Iranian population. Purpose: The aim of this study was to assess the root-crown ratio of permanent teeth with regards to the relationship of gender and jaw type using panoramic radiographs. The reliability of method was also assessed. Materials and Method: The crown and root lengths of teeth were measured by a digital caliper on panoramic radiographs of 185 individuals except for the third molars. A total of 1994 teeth was studied and 50.8% of the teeth belonged to males and 49.2% belonged to females. The modified Lind method was applied. Results: The highest mean root-crown ratios in both arches of both genders were obtained in the second premolars, followed by the first premolars and canines. In both genders, the lowest root-crown ratios were found in the maxillary central incisors. In male patients, the mean root-crown ratio was higher (p= 0.003) than that of females. Using Bland-Altman analysis, a non-significant difference of 0.006 (95% CI: -0.012-0.024) and 0.0002 (95% CI: -0.011-0.011) were found for intra-observer and inter-observer agreement, respectively. Conclusion: Assessment of the root-crown ratio in permanent dentition could be performed on panoramic radiographs with acceptable reproducibility in an Iranian Population. Considering observed differences, our findings suggest that for the accurate assessment, this ratio must be calculated for male and female patients and also for the upper and lower jaws, separately. PMID:25469356

  9. Comparison of clinical and dental panoramic findings: a practice-based crossover study

    PubMed Central

    2013-01-01

    Background Aim was to compare clinical findings with x-ray findings using dental panoramic radiography (DPR). In addition, type and frequency of secondary findings in x-rays were investigated. Methods Patients were selected on the basis of available DPRs (not older than 12 months). No therapeutic measures were permitted between the DPR and the clinical findings. The clinical findings were carried out by several investigators who had no knowledge of the purpose of the study. A calibrated investigator established the x-ray findings, independently and without prior knowledge of the clinical findings. The evaluation parameters for each tooth were: missing, healthy, carious, restorative or prosthetically sufficient or insufficient treatment. Type and frequency of additional findings in the DPR were documented, e.g. quality of a root canal filling and apical changes. Results Findings of 275 patients were available. Comparison showed a correspondence between clinical and radiographic finding in 93.6% of all teeth (n = 7,789). The differences were not significant (p > 0.05). Regarding carious as well as insufficiently restored or prosthetically treated teeth, respectively there were significant differences between the two methods (p < 0.05). The DPRs showed additional findings: root fillings in 259 teeth and 145 teeth with periapical changes. Conclusions With reference to the assessment of teeth, there was no difference between the two methods. However, in the evaluation of carious as well as teeth with insufficiently restorative or prosthetic treatment, there was a clear discrepancy between the two methods. Therefore, it would have been possible to have dispensed with x-rays. Nevertheless, additional x-ray findings were found. PMID:24066660

  10. A new screening pathway for identifying asymptomatic patients using dental panoramic radiographs

    NASA Astrophysics Data System (ADS)

    Hayashi, Tatsuro; Matsumoto, Takuya; Sawagashira, Tsuyoshi; Tagami, Motoki; Katsumata, Akitoshi; Hayashi, Yoshinori; Muramatsu, Chisako; Zhou, Xiangrong; Iida, Yukihiro; Matsuoka, Masato; Katagi, Kiyoji; Fujita, Hiroshi

    2012-03-01

    To identify asymptomatic patients is the challenging task and the essential first step in diagnosis. Findings of dental panoramic radiographs include not only dental conditions but also radiographic signs that are suggestive of possible systemic diseases such as osteoporosis, arteriosclerosis, and maxillary sinusitis. Detection of such signs on panoramic radiographs has a potential to provide supplemental benefits for patients. However, it is not easy for general dental practitioners to pay careful attention to such signs. We addressed the development of a computer-aided detection (CAD) system that detects radiographic signs of pathology on panoramic images, and the design of the framework of new screening pathway by cooperation of dentists and our CAD system. The performance evaluation of our CAD system showed the sensitivity and specificity in the identification of osteoporotic patients were 92.6 % and 100 %, respectively, and those of the maxillary sinus abnormality were 89.6 % and 73.6 %, respectively. The detection rate of carotid artery calcifications that suggests the need for further medical evaluation was approximately 93.6 % with 4.4 false-positives per image. To validate the utility of the new screening pathway, preliminary clinical trials by using our CAD system were conducted. To date, 223 panoramic images were processed and 4 asymptomatic patients with suspected osteoporosis, 7 asymptomatic patients with suspected calcifications, and 40 asymptomatic patients with suspected maxillary sinusitis were detected in our initial trial. It was suggested that our new screening pathway could be useful to identify asymptomatic patients with systemic diseases.

  11. A clinical comparison of image quality and patient exposure reduction in panoramic radiography with heavy metal filtration

    SciTech Connect

    Kapa, S.F.; Tyndall, D.A.

    1989-06-01

    Laboratory and clinical studies with the use of rare earth intensifying screens and four different forms of heavy metal elements serving as additional beam filtration were performed for panoramic radiography to identify the most efficacious system. Balanced density images were evaluated for contrast indices, resolution, relative dose reduction, and subjective image quality. Clinical studies were performed with a standard calcium tungstate imaging system and the four most promising experimental imaging systems that showed improvement over the standard system. Dosimetric studies were performed with the use of ionization chambers and thermoluminescent dosimetry (TLD) dosimeters. Exposure reductions of 34% to 79%, depending on the anatomic site and the imaging system used, were achieved. Subjective image quality was evaluated and analyzed statistically. This study concluded that the use of a Kodak Lanex regular screen/T-Mat G film with either Lanex screen or yttrium added beam filtration results in reduced patient exposure in panoramic radiography while image quality is maintained or improved.

  12. A clinical comparison of image quality and patient exposure reduction in panoramic radiography with heavy metal filtration.

    PubMed

    Kapa, S F; Tyndall, D A

    1989-06-01

    Laboratory and clinical studies with the use of rare earth intensifying screens and four different forms of heavy metal elements serving as additional beam filtration were performed for panoramic radiography to identify the most efficacious system. Balanced density images were evaluated for contrast indices, resolution, relative dose reduction, and subjective image quality. Clinical studies were performed with a standard calcium tungstate imaging system and the four most promising experimental imaging systems that showed improvement over the standard system. Dosimetric studies were performed with the use of ionization chambers and thermoluminescent dosimetry (TLD) dosimeters. Exposure reductions of 34% to 79%, depending on the anatomic site and the imaging system used, were achieved. Subjective image quality was evaluated and analyzed statistically. This study concluded that the use of a Kodak Lanex regular screen/T-Mat G film with either Lanex screen or yttrium added beam filtration results in reduced patient exposure in panoramic radiography while image quality is maintained or improved. PMID:2740096

  13. Doppler Sonography Confirmation in Patients Showing Calcified Carotid Artery Atheroma in Panoramic Radiography and Evaluation of Related Risk Factors

    PubMed Central

    Imanimoghaddam, Mahrokh; Rah Rooh, Mohammad; Mahmoudi Hashemi, Elahe; Javadzade Blouri, Abbas

    2012-01-01

    Background and aims The purpose of this study was to identify patients at the risk of cerebrovascular attack (CVA) by detecting calcified carotid artery atheroma (CCAA) in panoramic radiography and evaluating their risk factors. Materials and methods A total of 960 panoramic radiographs of patients above 40 years old were evaluated. Doppler Sonography (DS) was performed for patients who showed calcified carotid artery atheroma (CCAA) in panoramic radiogra-phy in order to determine the presence of CCAA and the degree of stenosis. Cardiovascular risk factors in both groups of patients with CCAA (12 subjects) and without CCAA (3 subjects) were compared using a questionnaire filled out by the patients. Statistical analysis including Fisher and independent t-test applied for data analysis. Results Fifteen patients (30 sides) showed calcification in their panoramic radiographs, and underwent DS which revealed CCAA in 16 sides (12 patients). Two patients (13.33%) showed stenosis greater than 70%. Among the risk factors, only age showed a significant association with the occurrence of carotid calcified atheroma (P=0.026). Conclusion Considering the results, dentists should refer especially elderly patients with radiographically identified atheromas for further examinations, as asymptomatic CCAA might be associated with high degrees of stenosis. PMID:22991627

  14. A benchmark for comparison of dental radiography analysis algorithms.

    PubMed

    Wang, Ching-Wei; Huang, Cheng-Ta; Lee, Jia-Hong; Li, Chung-Hsing; Chang, Sheng-Wei; Siao, Ming-Jhih; Lai, Tat-Ming; Ibragimov, Bulat; Vrtovec, Tomaž; Ronneberger, Olaf; Fischer, Philipp; Cootes, Tim F; Lindner, Claudia

    2016-07-01

    Dental radiography plays an important role in clinical diagnosis, treatment and surgery. In recent years, efforts have been made on developing computerized dental X-ray image analysis systems for clinical usages. A novel framework for objective evaluation of automatic dental radiography analysis algorithms has been established under the auspices of the IEEE International Symposium on Biomedical Imaging 2015 Bitewing Radiography Caries Detection Challenge and Cephalometric X-ray Image Analysis Challenge. In this article, we present the datasets, methods and results of the challenge and lay down the principles for future uses of this benchmark. The main contributions of the challenge include the creation of the dental anatomy data repository of bitewing radiographs, the creation of the anatomical abnormality classification data repository of cephalometric radiographs, and the definition of objective quantitative evaluation for comparison and ranking of the algorithms. With this benchmark, seven automatic methods for analysing cephalometric X-ray image and two automatic methods for detecting bitewing radiography caries have been compared, and detailed quantitative evaluation results are presented in this paper. Based on the quantitative evaluation results, we believe automatic dental radiography analysis is still a challenging and unsolved problem. The datasets and the evaluation software will be made available to the research community, further encouraging future developments in this field. (http://www-o.ntust.edu.tw/~cweiwang/ISBI2015/). PMID:26974042

  15. Anatomical characteristics and visibility of mental foramen and accessory mental foramen: Panoramic radiography vs. cone beam CT

    PubMed Central

    Muinelo-Lorenzo, Juan; Suárez-Quintanilla, Juan-Antonio; Fernández-Alonso, Ana; Varela-Mallou, Jesús

    2015-01-01

    Background The mental foramen (MF) is a small foramen located in the anterolateral region of the mandible through which the mental nerve and vessels emerge. The knowledge on the anatomic characteristics and variations of MF is very important in surgical procedures involving that area. The aim of this study was two-fold: firstly, to analyze the anatomic characteristics of MF and the presence of accessory mental foramen (AMF) using CBCT and, secondly, to compare the capability of CBCT and PAN in terms of MF and AMF visualization, as well as influencing factors. Material and Methods A sample of 344 CBCT scans was analyzed for presence and characteristics (i.e. diameter, area, shape, exit angle) of MF and AMF. Subsequently, corresponding PANs were analyzed to ascertain whether MF and AMF were visible. Results Out of the 344 patients, 344 (100%) MFs and 45 (13%) AMFs were observed on CBCT. Regarding gender, MF diameter and area, MF-MIB and MF-MSB distances, and exit angle were all significantly higher in males. Also, statistically significant differences were found in terms of age and dental status. Statistically significant differences in MF long and short diameters and MF area were found with respect to AMF presence (p=.021, p=.008, p=.021). Only 83.87% of the MFs and 45.83% of the AMFs identified on CBCT were also visible on PANs. MF diameter, shape, exit angle, and age had a significant influence on MF visualization on PAN (B=.43, p=.005; B=-.55, p=.020; B=.20, p=.008; B=.61, p=.005). Conclusions PAN is not an adequate technique to properly identify MF and AMF. Diameter, shape, exit angle, and age are all factors influencing MF visualization on PAN images. For surgery involving the MF anatomical region, a preoperative radiological study with CBCT is of crucial importance to avoid complications. Key words:Mental foramen, accessory mental foramen, mandibular anatomy, cone beam computed tomography, panoramic radiography. PMID:26449429

  16. An automatic early stage alveolar-bone-resorption evaluation method on digital dental panoramic radiographs

    NASA Astrophysics Data System (ADS)

    Zhang, Min; Katsumata, Akitoshi; Muramatsu, Chisako; Hara, Takeshi; Suzuki, Hiroki; Fujita, Hiroshi

    2014-03-01

    Periodontal disease is a kind of typical dental diseases, which affects many adults. The presence of alveolar bone resorption, which can be observed from dental panoramic radiographs, is one of the most important signs of the progression of periodontal disease. Automatically evaluating alveolar-bone resorption is of important clinic meaning in dental radiology. The purpose of this study was to propose a novel system for automated alveolar-bone-resorption evaluation from digital dental panoramic radiographs for the first time. The proposed system enables visualization and quantitative evaluation of alveolar bone resorption degree surrounding the teeth. It has the following procedures: (1) pre-processing for a test image; (2) detection of tooth root apices with Gabor filter and curve fitting for the root apex line; (3) detection of features related with alveolar bone by using image phase congruency map and template matching and curving fitting for the alveolar line; (4) detection of occlusion line with selected Gabor filter; (5) finally, evaluation of the quantitative alveolar-bone-resorption degree in the area surrounding teeth by simply computing the average ratio of the height of the alveolar bone and the height of the teeth. The proposed scheme was applied to 30 patient cases of digital panoramic radiographs, with alveolar bone resorption of different stages. Our initial trial on these test cases indicates that the quantitative evaluation results are correlated with the alveolar-boneresorption degree, although the performance still needs further improvement. Therefore it has potential clinical practicability.

  17. Technetium-99m Bone Scan and Panoramic Radiography in Detection of Bone Invasion by Oral Carcinoma

    PubMed Central

    John, Ani

    2014-01-01

    Objective: The correct extension of cancer in the bone usually remains undetected on static imaging which may lead to inadequate or over excision. The conventional radiography as well as other anatomical imaging modalities like computed tomography, magnetic resonance imaging often fails to detect functional changes in the bone. However, bone scinitigraphy is highly sensitive in detecting earlier changes in the bone but lack anatomical definition. The purpose of the study was to evaluate the accuracy of combining technetium-99m bone scan and panoramic radiography (Tc scan/PR) over using single diagnostic modality in detection of jaw bone invasion by oral carcinomas. The accuracy of these imaging modalities either alone or in combination were determined by comparing with the histopathological findings. Materials and Methods: Twenty patients with biopsy-proven oral malignant tumors were randomly selected from Oral Medicine and Radiology department over a period of two years. All patients were investigated preoperatively by Tc scan and PR. Lewis – Jones’s designed diagnostic criterion was applied on Tc scan/PR to evaluate bone involvement by cancer. To test the accuracy of Tc scan, PR and Tc scan/PR, their results were compared with the histopathological findings of resected specimen. Results: Hybrid Tc scan/PR had higher specificity, accuracy and positive predictive value (83.3%, 94.7%, 92.8%) than Tc scan alone (50%, 84.2%, 81.2%) and higher sensitivity and negative predictive value (100%, 100%) than PR (69.2%, 55.5%). Conclusion: Combination of Tc scan and PR was more accurate in detecting jaw bone invasion by oral squamous cell carcinoma than Tc scan and PR alone. PMID:24995244

  18. The Efficacy of the Graft Materials after Sinus Elevation: Retrospective Comparative Study Using Panoramic Radiography

    PubMed Central

    Jeong, Tae Min; Lee, Jeong Keun

    2014-01-01

    Purpose: This study compares and evaluates the efficacy of graft materials after maxillary sinus bone grafts with autogenous tooth bone graft material (AutoBT), demineralized freeze-dried bone allograft (DFDBA) and deproteinized bovine bone mineral (DBBM). Methods: The study involved 30 sinuses in 26 patients who visited the Division of Oral and Maxillofacial Surgery, Department of Dentistry in Ajou University Hospital and received either AutoBT, DFDBA or DBBM with sinus elevation using the lateral window technique. Sinus graft height was measured before, immediately after, and six months after bone graft with panoramic radiography and the height changes of the sinus floor was compared according to the graft materials. Results: After six months, the decrease ratio of graft heights were 13.57% for AutoBT group, 14.30% for DFDBA group, and 11.92% for DBBM group. There was no statistically significant difference. Conclusion: The new maxillary sinus floor formed by the upper border of bone graft material, can repneumatize after the maxillary sinus elevation. Thus, long-term stability of sinus graft height represents an important factor for implant success. We found that the three graft materials for sinus elevation do not differ significantly and all three graft materials showed excellent resistance to maxillary sinus repneumatization. However, due to the special circumstances of the maxillary sinus and small sample, the actual difference between the three graft materials may not have been detectable. Therefore further study needs to be conducted for more reliable study results. PMID:27489826

  19. Bone Scintigraphy and Panoramic Radiography in Deciding the Extent of Bone Resection in Benign Jaw Lesions

    PubMed Central

    Jamdade, Anshuman; John, Ani

    2013-01-01

    Objective: To find out the value of correlating radiographic and scintigraphic imaging for defining the extent and nature of benign jaw lesions (BJL). Material and Methods: Twenty patients with histologically proven benign lesions of the jaws were investigated pre-operatively by panoramic radiography (PR) and bone scintigraphy (BS). To test the efficacy of combination of these two imaging modalities, their results were compared with intra-operative and histopathological findings. Result: Most of the benign lesions presented radiographically as well-defined bone destructions with fine sclerotic rims. Such lesions were found to be silent on scintigraphs and the extent of radionuclide uptake was same as radiographically visible extent of bone involvement. However, aggressive lesions showed ill-defined bone destructions without sclerotic rims on radiographs and their scintigraphic uptake correctly exceeded the radiographic extent of the bone involvement. Conclusion: The efficacy of combination of both complementary imagings is rewarding in defining the extent of the BJL, especially when radiographic margins are not so well defined. So, that surgical excisions will be complete and the possibility recurrences is reduced. PMID:24298527

  20. Automatic Molar Extraction from Dental Panoramic Radiographs for Forensic Personal Identification

    NASA Astrophysics Data System (ADS)

    Samopa, Febriliyan; Asano, Akira; Taguchi, Akira

    Measurement of an individual molar provides rich information for forensic personal identification. We propose a computer-based system for extracting an individual molar from dental panoramic radiographs. A molar is obtained by extracting the region-of-interest, separating the maxilla and mandible, and extracting the boundaries between teeth. The proposed system is almost fully automatic; all that the user has to do is clicking three points on the boundary between the maxilla and the mandible.

  1. Automated contralateral subtraction of dental panoramic radiographs for detecting abnormalities in paranasal sinus

    NASA Astrophysics Data System (ADS)

    Hara, Takeshi; Mori, Shintaro; Kaneda, Takashi; Hayashi, Tatsuro; Katsumata, Akitoshi; Fujita, Hiroshi

    2011-03-01

    Inflammation in the paranasal sinus is often observed in seasonal allergic rhinitis or with colds, but is also an indication for odontogenic tumors, carcinoma of the maxillary sinus or a maxillary cyst. The detection of those findings in dental panoramic radiographs is not difficult for radiologists, but general dentists may miss the findings since they focus on treatments of teeth. The purpose of this work is to develop a contralateral subtraction method for detecting the odontogenic sinusitis region on dental panoramic radiographs. We developed a contralateral subtraction technique in paranasal sinus region, consisting of 1) image filtering of the smoothing and sobel operation for noise reduction and edge extraction, 2) image registration of mirrored image by using mutual information, and 3) image display method of subtracted pixel data. We employed 56 cases (24 normal and 32 abnormal). The abnormal regions and the normal cases were verified by a board-certified radiologist using CT scans. Observer studies with and without subtraction images were performed for 9 readers. The true-positive rate at a 50% confidence level in 7 out of 9 readers was improved, but there was no statistical significance in the difference of area-under-curve (AUC) in each radiologist. In conclusion, the contralateral subtraction images of dental panoramic radiographs may improve the detection rate of abnormal regions in paranasal sinus.

  2. Computers in dental radiography: a scenario for the future

    SciTech Connect

    Webber, R.L.

    1985-09-01

    The recent emergence of cost-effective computing power makes it possible to integrate sophisticated data-sampling and image-interpretation techniques into dental radiography for the first time. A prototype system is being developed to permit clinical information expressed in three dimensions--plus time--to be made visible almost instantly. The associated X-ray dose for a complete three-dimensional survey of a selected dental region is predicted to be less than that required for a single conventional periapical radiograph exposed on D-speed film.

  3. Panoramic radiography and cone-beam computed tomography findings in preoperative examination of impacted mandibular third molars

    PubMed Central

    2014-01-01

    Background Preoperative radiographic examination of impacted mandibular third molars (IMTM) is essential to prevent inferior alveolar nerve injury during extraction. The purpose of this study was to evaluate the correlation between cone-beam computed tomography (CBCT) and digital panoramic radiography (DPR) findings in preoperative examination of IMTM. Methods This retrospective study included 298 teeth in 191 individuals. The relationship between the inferior alveolar canal (IAC) and the IMTM (buccal, lingual, interradicular or inferior), the position of the IMTM with respect to the IAC (contact, no contact), the morphologic shape of the mandible in the IMTM region (round, lingual extended, lingual concave), the type of IMTM (vertical, horizontal or angular) and the number of roots of the IMTM were evaluated on CBCT images. DPR images were evaluated for the number of roots of the IMTM and for the most common radiographic findings indicating a relationship between the IAC and the IMTM (darkening of the roots, diversion of the IAC, narrowing of the IAC and interruption of the white line). Data were statistically analyzed with Cramer V coefficient, Kappa statistic, chi-square and Fisher’s exact test. Results There was a significant difference in number of roots detected on DPR versus CBCT images. There was a significant association between the type of IMTM and the morphologic shape of the mandible on CBCT images. Darkening of the roots and interruption of the white line on DPR images were significantly associated with the presence of contact between the IMTM and the IAC on CBCT images. Conclusions Panoramic radiography is inadequate, whereas CBCT is useful to detect multiple roots of IMTM. When darkening of the roots and interruption of the white line are observed on panoramic images, there is increased likelihood of contact between the IMTM and the IAC. CBCT is required in these cases. PMID:24928108

  4. Coincidence of calcified carotid atheromatous plaque, osteoporosis, and periodontal bone loss in dental panoramic radiographs

    PubMed Central

    Soroushian, Sheila; Ganguly, Rumpa

    2013-01-01

    Purpose This study was performed to assess the correlation of calcified carotid atheromatous plaque (CCAP), the mandibular cortical index, and periodontal bone loss in panoramic radiographs. Materials and Methods One hundred eighty-five panoramic radiographs with CCAP and 234 without this finding were evaluated by 3 observers for the presence of osseous changes related to osteoporosis and periodontal bone loss. Chi-squared and Mann-Whitney U tests were used to compare the two groups for an association of CCAP with the mandibular cortical index and periodontal bone loss, respectively. Results There was a statistically significant coincidence of CCAP and osseous changes related to osteopenia/osteoporosis, with a p-value <0.001. There was no statistically significant coincidence of CCAP and periodontal bone loss. When comparing the 2 groups, "With CCAP" and "Without CCAP", there was a statistically significant association with the mean body mass index (BMI), number of remaining teeth, positive history of diabetes mellitus, and vascular accidents. There was no statistically significant association with gender or a history of smoking. Conclusion This study identified a possible concurrence of CCAP and mandibular cortical changes secondary to osteopenia/osteoporosis in panoramic radiographs. This could demonstrate the important role of dental professionals in screening for these systemic conditions, leading to timely and appropriate referrals resulting in early interventions and thus improving overall health. PMID:24380062

  5. The subjective image quality of direct digital and conventional panoramic radiography.

    PubMed

    Gijbels, F; De Meyer, A M; Bou Serhal, C; Van den Bossche, C; Declerck, J; Persoons, M; Jacobs, R

    2000-09-01

    One of the main advantages of digital imaging is the possibility of altering display options for improved image interpretation. The aim of the present study was to evaluate the subjective image quality of direct digital panoramic images and compare the results with those obtained from conventional images. Furthermore, the effect of various filter settings on image interpretation was assessed. Panoramic images were obtained with three different types of panoramic equipment (one direct digital and two conventional units) from three groups of 54 patients with a natural dentition in all quadrants. The first series of panoramic images consisted of 54 unprocessed digital images; conventional film images (n = 108) comprised the second and third series. A final series consisted of the digital images treated with three different filters ("smoothening," "sharpening," and "contrast enhancement"). All images were scored randomly by four experts in oral radiology on a 4-point rating scale. The results showed a statistically significant difference in scorings between the conventional and digital panoramic units. The main reason for poor image quality appeared to be a combination of blurring and overlapping in the panoramic image. The premolar region in the upper jaw was the region where most additional radiographs were needed. PMID:11000322

  6. Free focus radiography with miniaturized dental x-ray machines: a comparison of ''midline'' and ''lateral'' techniques

    SciTech Connect

    Jensen, T.W.

    1983-08-01

    The use of free focus radiography (FFR) employing miniaturized dental x-ray machines with radiation probes has never been generally accepted in dentistry despite its recognized radiographic potential. The present investigation studied ways to improve imaging and lower radiation burdens in dental free focus radiography. Relatively high air exposures ranging from 42,050 mR per film for high-resolution images to 3,214 mR per film for lower-resolution images using a current midline radiographic technique for panoramic FFR were found. In a proposed lateral FFR panoramic technique, reduced exposures ranged from 420 mR per film for high-resolution images to 14 mR per film for lower-resolution images. In each technique the lower exposure was obtained with a rare earth imaging system. A proposed modification of the current midline FFR technique using a rare earth imaging system and heavy added copper filtration was found to produce exposures in the range normally used in dentistry (207 mr), and the resultant image was high in contrast with relatively low detail. A comparison of essential characteristics of midline and lateral FFR techniques failed to identify specific advantages for the midline technique in current use. Lateral exposure modes in dental FFR should receive increased attention in the interest of good imaging and radiation control. It was noted that existing miniaturized dental x-ray machines may have been designed specifically for use of the midline FFR exposure technique, and modification of this equipment to support reliable lateral exposure modes was recommended.

  7. A note on digital dental radiography in forensic odontology

    PubMed Central

    Chiam, Sher-Lin

    2014-01-01

    Digital dental radiography, intraoral and extraoral, is becoming more popular in dental practice. It offers convenience, such as lower exposure to radiation, ease of storing of images, and elimination of chemical processing. However, it also has disadvantages and drawbacks. One of these is the potential for confusion of the orientation of the image. This paper outlines one example of this, namely, the lateral inversion of the image. This source of confusion is partly inherent in the older model of phosphor storage plates (PSPs), as they allow both sides to be exposed without clue to the fact that the image is acquired on the wrong side. The native software allows digital manipulation of the X-ray image, permitting both rotation and inversion. Attempts to orientate the X-ray according to the indicator incorporated on the plate can then sometimes lead to inadvertent lateral inversion of the image. This article discusses the implications of such mistakes in dental digital radiography to forensic odontology and general dental practice. PMID:25177144

  8. Image optimization in digital dental radiography.

    PubMed

    Silverstrim, Kelli J; Schneider, Erich; van der Hoeven, Christopher

    2015-06-01

    Presented is a method for establishing the appropriate balance of image quality and radiation dose for dental imaging. Using the Monte Carlo N-Particle Extended (MCNPX) radiation transport code, the DC Planmeca radiographic unit and a dental bitewing phantom were modeled. The Carestream 6100 RVG sensor signal response, noise response, dose rate dependence, and reproducibility were determined experimentally, including uncertainties and inter/intraunit variabilities. The computationally varied parameters were peak kilovoltage and tube filtration. The entrance air kerma for the current clinical technique was used to establish reference image quality. Four figures of merit (FOM) were chosen to encompass parameter variation. With equal weighting of FOMs and no equipment limitations, the optimal parameters were 90 kVp with 0.1 mm added copper filtration. The optimal technique in the radiographic units' operating range was 70 kVp and 0.1 mm added copper filtration, resulting in a ∼50% (±17%) entrance dose and ∼40% effective dose savings. PMID:25905519

  9. Influence of Experience and Training on Dental Students' Examination Performance Regarding Panoramic Images.

    PubMed

    Turgeon, Daniel P; Lam, Ernest W N

    2016-02-01

    Physician training has greatly benefitted from insights gained in understanding the manner in which experts search medical images for abnormalities. The aims of this study were to compare the search patterns of 30 fourth-year dental students and 15 certified oral and maxillofacial radiologists (OMRs) over panoramic images and to determine the most robust variables for future studies involving image visualization. Eye tracking was used to capture the eye movement patterns of both subject groups when examining 20 panoramic images classified as normal or abnormal. Abnormal images were further subclassified as having an obvious, intermediate, or subtle abnormality. The images were presented in random order to each participant, and data were collected on duration of the participants' observations and total distance tracked, time to first eye fixation, and total duration and numbers of fixations on and off the area of interest (AOI). The results showed that the OMRs covered greater distances than the dental students (p<0.001) for normal images. For images of pathosis, the OMRs required less total time (p<0.001), made fewer eye fixations (p<0.01) with fewer saccades (p<0.001) than the students, and required less time before making the first fixation on the AOI (p<0.01). Furthermore, the OMRs covered less distance (p<0.001) than the dental students for obvious pathoses. For investigations of images of pathosis, time to first fixation is a robust parameter in predicting ability. For images with different levels of subtlety of pathoses, the number of fixations, total time spent, and numbers of revisits are important parameters to analyze when comparing observer groups with different levels of experience. PMID:26834133

  10. Dose measurements for dental cone-beam CT: a comparison with MSCT and panoramic imaging.

    PubMed

    Deman, P; Atwal, P; Duzenli, C; Thakur, Y; Ford, N L

    2014-06-21

    To date there is a lack of published information on appropriate methods to determine patient doses from dental cone-beam computed tomography (CBCT) equipment. The goal of this study is to apply and extend the methods recommended in the American Association of Physicists in Medicine (AAPM) Report 111 for CBCT equipment to characterize dose and effective dose for a range of dental imaging equipment. A protocol derived from the one proposed by Dixon et al (2010 Technical Report 111, American Association of Physicist in Medicine, MD, USA), was applied to dose measurements of multi-slice CT, dental CBCT (small and large fields of view (FOV)) and a dental panoramic system. The computed tomography dose index protocol was also performed on the MSCT to compare both methods. The dose distributions in a cylindrical polymethyl methacrylate phantom were characterized using a thimble ionization chamber and Gafchromic™ film (beam profiles). Gafchromic™ films were used to measure the dose distribution in an anthropomorphic phantom. A method was proposed to extend dose estimates to planes superior and inferior to the central plane. The dose normalized to 100 mAs measured in the center of the phantom for the large FOV dental CBCT (11.4 mGy/100 mAs) is two times lower than that of MSCT (20.7 mGy/100 mAs) for the same FOV, but approximately 15 times higher than for a panoramic system (0.6 mGy/100 mAs). The effective dose per scan (in clinical conditions) found for the dental CBCT are 167.60 ± 3.62, 61.30 ± 3.88 and 92.86 ± 7.76 mSv for the Kodak 9000 (fixed scan length of 3.7 cm), and the iCAT Next Generation for 6 cm and 13 cm scan lengths respectively. The method to extend the dose estimates from the central slice to superior and inferior slices indicates a good agreement between theory and measurement. The Gafchromic™ films provided useful beam profile data and 2D distributions of dose in phantom. PMID:24862349

  11. Dose measurements for dental cone-beam CT: a comparison with MSCT and panoramic imaging

    NASA Astrophysics Data System (ADS)

    Deman, P.; Atwal, P.; Duzenli, C.; Thakur, Y.; Ford, N. L.

    2014-06-01

    To date there is a lack of published information on appropriate methods to determine patient doses from dental cone-beam computed tomography (CBCT) equipment. The goal of this study is to apply and extend the methods recommended in the American Association of Physicists in Medicine (AAPM) Report 111 for CBCT equipment to characterize dose and effective dose for a range of dental imaging equipment. A protocol derived from the one proposed by Dixon et al (2010 Technical Report 111, American Association of Physicist in Medicine, MD, USA), was applied to dose measurements of multi-slice CT, dental CBCT (small and large fields of view (FOV)) and a dental panoramic system. The computed tomography dose index protocol was also performed on the MSCT to compare both methods. The dose distributions in a cylindrical polymethyl methacrylate phantom were characterized using a thimble ionization chamber and Gafchromic™ film (beam profiles). Gafchromic™ films were used to measure the dose distribution in an anthropomorphic phantom. A method was proposed to extend dose estimates to planes superior and inferior to the central plane. The dose normalized to 100 mAs measured in the center of the phantom for the large FOV dental CBCT (11.4 mGy/100 mAs) is two times lower than that of MSCT (20.7 mGy/100 mAs) for the same FOV, but approximately 15 times higher than for a panoramic system (0.6 mGy/100 mAs). The effective dose per scan (in clinical conditions) found for the dental CBCT are 167.60 ± 3.62, 61.30 ± 3.88 and 92.86 ± 7.76 mSv for the Kodak 9000 (fixed scan length of 3.7 cm), and the iCAT Next Generation for 6 cm and 13 cm scan lengths respectively. The method to extend the dose estimates from the central slice to superior and inferior slices indicates a good agreement between theory and measurement. The Gafchromic™ films provided useful beam profile data and 2D distributions of dose in phantom.

  12. Soft tissue calcified in mandibular angle area observed by means of panoramic radiography

    PubMed Central

    Garay, Ivonne; Netto, Henrique Duque; Olate, Sergio

    2014-01-01

    The aim of this research is to determine the prevalence of soft tissue calcifications detectable on panoramic radiographs, in the mandibular angle area. 3,028 digital panoramic radiographs taken between June 2009 and June 2011 were evaluated. Soft tissue calcifications found in the mandibular angle area were recorded according to gender, age and bilaterality. Data were analyzed with the Chi squared test and Fisher’s exact test, with α< 0.05 being considered statistically significant. The panoramic radiographs analyzed revealed a total of 79 calcifications (2.61%) in 75 individuals, of which 55.7% were women and 44.3% were men. The calcifications found were tonsilloliths (56%), carotid artery calcification (29%), sialoliths (11%), calcified lymph nodes (4%). A statistically significant link was found between being over age 40 with tonsilloliths (p<0.001) and calcifications of the carotid artery (p<0.001). In terms of gender, men had a higher likelihood of tonsilloliths (p=0.007). Conclusions There is a low prevalence of soft tissue calcifications detectable on panoramic radiographs, which increases with age. PMID:24482688

  13. Automated classification of mandibular cortical bone on dental panoramic radiographs for early detection of osteoporosis

    NASA Astrophysics Data System (ADS)

    Horiba, Kazuki; Muramatsu, Chisako; Hayashi, Tatsuro; Fukui, Tatsumasa; Hara, Takeshi; Katsumata, Akitoshi; Fujita, Hiroshi

    2015-03-01

    Findings on dental panoramic radiographs (DPRs) have shown that mandibular cortical index (MCI) based on the morphology of mandibular inferior cortex was significantly correlated with osteoporosis. MCI on DPRs can be categorized into one of three groups and has the high potential for identifying patients with osteoporosis. However, most DPRs are used only for diagnosing dental conditions by dentists in their routine clinical work. Moreover, MCI is not generally quantified but assessed subjectively. In this study, we investigated a computer-aided diagnosis (CAD) system that automatically classifies mandibular cortical bone for detection of osteoporotic patients at early stage. First, an inferior border of mandibular bone was detected by use of an active contour method. Second, regions of interest including the cortical bone are extracted and analyzed for its thickness and roughness. Finally, support vector machine (SVM) differentiate cases into three MCI categories by features including the thickness and roughness. Ninety eight DPRs were used to evaluate our proposed scheme. The number of cases classified to Class I, II, and III by a dental radiologist are 56, 25 and 17 cases, respectively. Experimental result based on the leave-one-out cross-validation evaluation showed that the sensitivities for the classes I, II, and III were 94.6%, 57.7% and 94.1%, respectively. Distribution of the groups in the feature space indicates a possibility of MCI quantification by the proposed method. Therefore, our scheme has a potential in identifying osteoporotic patients at an early stage.

  14. Automated scheme for measuring mandibular cortical thickness on dental panoramic radiographs for osteoporosis screening

    NASA Astrophysics Data System (ADS)

    Matsumoto, T.; Hayashi, T.; Hara, T.; Katsumata, A.; Muramatsu, C.; Zhou, X.; Iida, Y.; Matsuoka, M.; Katagi, Ki.; Fujita, H.

    2012-03-01

    Findings of dental panoramic radiographs (DPRs) have shown that the mandibular cortical thickness (MCT) was significantly correlated with osteoporosis. Identifying asymptomatic patients with osteoporosis through dental examinations may bring a supplemental benefit for the patients. However, most of the DPRs are used for only diagnosing dental conditions by dentists in their routine clinical work. The aim of this study was to develop a computeraided diagnosis scheme that automatically measures MCT to assist dentists in screening osteoporosis. First, the inferior border of mandibular bone was detected by use of an active contour method. Second, the locations of mental foramina were estimated on the basis of the inferior border of mandibular bone. Finally, MCT was measured on the basis of the grayscale profile analysis. One hundred DPRs were used to evaluate our proposed scheme. Experimental results showed that the sensitivity and specificity for identifying osteoporotic patients were 92.6 % and 100 %, respectively. We conducted multiclinic trials, in which 223 cases have been obtained and processed in about a month. Our scheme succeeded in detecting all cases of suspected osteoporosis. Therefore, our scheme may have a potential to identify osteoporotic patients at an early stage.

  15. Diagnostic Efficacy of Panoramic Radiography in Detection of Osteoporosis in Post-Menopausal Women with Low Bone Mineral Density

    PubMed Central

    Bhatnagar, Sunanda; Krishnamurthy, Vasavi; Pagare, Sandeep S.

    2013-01-01

    Objective: The aim of the study was to evaluate panoramic radiograph, a commonly taken dental radiograph as a screening tool to detect early osseous changes (normal, mildly or severely eroded) of the mandibular inferior cortex and measure the mandibular cortical width (CW) in post-menopausal women and correlate it with the bone mineral density (BMD) measured by the ultrasound bone sonometer at the mid-shaft tibia region. Materials and Methods: The study included females between 45 years and 65 years of age in their post-menopausal stage (no menstruation for at least 6-12 months). Mandibular indices (mandibular CW and mandibular cortical shape) were evaluated from panoramic radiographs. The BMD assessment was carried out at the mid-shaft tibia region, exactly half-way between the heel and the knee joint perpendicular to the direction of the bone, using an ultrasound bone sonometer. It is a non-invasive device designed for quantitative measurement of the velocity of ultrasound waves as speed of sound in m/s, capable of measuring bone density at one or more skeletal sites. Using 1994 WHO criteria the study subjects were categorized as Group 1: Normal, Group 2: Osteopenia, Group 3: Osteoporosis. (WHO T score for tibia BMD can be used as a standard). Results: The diagnostic efficacy of the panoramic radiograph in detecting osseous changes in post-menopausal women with low BMD was shown to have 96% specificity and 60% sensitivity with mandibular cortical shape and 58% specificity and 73% sensitivity with mandibular CW measurement. Factorial ANOVA analysis carried out indicated a significant correlation of BMD classification with mandibular cortical shape (F = 29.0, P < 0.001, partial eta squared [η2] =0.85), a non-significant correlation with mandibular CW, (F = 1.6, P = 0.23, η2 = 0.86), and a more significant correlation with combined cortical shape and width (F = 3.3, P < 0.05, η2 = 0.70). Conclusion: The study concludes that the combined mandibular cortical

  16. Evaluation of developmental dental anomalies in digital panoramic radiographs in Southeast Iranian Population

    PubMed Central

    Saberi, Eshagh Ali; Ebrahimipour, Sediqe

    2016-01-01

    Objectives: The objective of this study was to evaluate the prevalence of dental developmental anomalies in digital panoramic radiographs of the patients referred to the Zahedan medical imaging center and to evaluate the frequency of anomalies regarding the disorders in shape, position and number in the Southeast of Iran. Materials and Methods: A total of 1172 panoramic radiographs from 581 males and 586 females aged over 16 years were obtained from the files of the Zahedan medical imaging center between the years of 2014 and 2015. The selected radiographs were evaluated in terms of the anomalies such as dilacerations, taurodontism, supernumerary teeth, congenitally missing teeth, fusion, gemination, tooth impaction, tooth transposition, dens invagination, and peg lateral. Then, the anomalies were compared to each other regarding the frequency of the anomaly type (morphological, positional and numerical). Data were evaluated using descriptive statistics such as frequency and percent, and statistical tests such as X2 at 0.05 significant level using the Statistical Package for the Social Sciences version 16.5. Results: The prevalence of dental anomaly was 213 (18.17%), which was higher in females (9.90) than male, (8.28), however, this difference was not statistically significant (P > 0.05). The prevalence of dilacerated teeth was 62 (5.29%), taurodontism 63 (5.38%), supernumerary teeth 6 (0.51%), congenitally missing teeth 13 (1.11%), fusion 1 (0.09%), gemination 1 (0.09%), impaction 40 (3.41%), transposition 2 (0.18%), dens invagination 16 (1.37) and peg lateral was 9 (0.77%). The prevalence of morphological anomaly was 152 (71.36%), malposition 42 (19.72%) and numerous anomaly was 19 (8.92%). Conclusions: Dental anomalies are relatively common; although their occurrence is not symptomatic, they can lead to several clinical problems in patients. Detailed clinical and radiographic assessment and counseling during patient visits is a critical factor in assessing the

  17. Comparison of spatial resolution between tomographic images and ghosts in rotational panoramic radiography: the effect of the first slit width.

    PubMed

    Wakoh, M; Yamamoto, K; Fujimori, H; Kuroyanagi, K

    1992-11-01

    Rotational panoramic radiography projects the object placed within the focal trough as tomographic images with minimal distortion. However, even if an object is within the focal trough, the sharpness of the image is affected by the position of the object, the difference in the relative speed of the X-ray source against the film and the difference in the direction of rotation. In this study, spatial resolutions of ghosts and tomographic images were compared. Ghosts, as well as tomographic images, were obtained from the object placed in the focal trough. The effects of the width of the first slit, a major parameter affecting image quality, were the primary concern in this study. With regard to ghosts, the influence of the position of object, in terms of central, buccal and lingual regions the focal trough, was also analyzed. The target of analysis was the mandibular ramus region. An Orthopantomograph OP5, a conventional panoramic apparatus, was used. An X-ray test chart, X-ray beams, and H-D curve were prepared for calculation of the Modulation Transfer Function (MTF), and the slit method using the Fourier transforms was applied. When the width of the first slit was changed displacement of MTF curves was most remarkable for the superimposed tomographic image which was scanned 10 mm posterior to the X-axis connecting the right and left lateral rotation centers. For reduction of the spatial resolution of ghosts, it was found effective to use a wider slit and place the object at a position lingual to the central plane. PMID:1303325

  18. Geometrical modeling of complete dental shapes by using panoramic X-ray, digital mouth data and anatomical templates.

    PubMed

    Barone, Sandro; Paoli, Alessandro; Razionale, Armando Viviano

    2015-07-01

    In the field of orthodontic planning, the creation of a complete digital dental model to simulate and predict treatments is of utmost importance. Nowadays, orthodontists use panoramic radiographs (PAN) and dental crown representations obtained by optical scanning. However, these data do not contain any 3D information regarding tooth root geometries. A reliable orthodontic treatment should instead take into account entire geometrical models of dental shapes in order to better predict tooth movements. This paper presents a methodology to create complete 3D patient dental anatomies by combining digital mouth models and panoramic radiographs. The modeling process is based on using crown surfaces, reconstructed by optical scanning, and root geometries, obtained by adapting anatomical CAD templates over patient specific information extracted from radiographic data. The radiographic process is virtually replicated on crown digital geometries through the Discrete Radon Transform (DRT). The resulting virtual PAN image is used to integrate the actual radiographic data and the digital mouth model. This procedure provides the root references on the 3D digital crown models, which guide a shape adjustment of the dental CAD templates. The entire geometrical models are finally created by merging dental crowns, captured by optical scanning, and root geometries, obtained from the CAD templates. PMID:25670149

  19. Patient exposure trends in medical and dental radiography

    SciTech Connect

    Johnson, D.W.; Goetz, W.A.

    1986-01-01

    Patient exposure to medical and dental x rays has long been of interest to the radiological health community. With the cooperation of state and local agencies and professional groups, the Center for Devices and Radiological Health has conducted three major surveys of patient exposure to x rays. The latest of these surveys, the Nationwide Evaluation of X-ray Trends (NEXT), collected x-ray exposure data for each year starting in 1972. Two earlier studies, the 1964 and 1970 X-ray Exposure Studies collected x-ray data during the years these surveys were conducted. Exposure trends presented are based on results of all three studies. Major improvements in beam limitation are seen for medical and dental radiography. Since 1964, when the first nationwide survey was conducted, dental exposures have decreased about 75%. Decreases of up to one-third occurred in exposures for medical examinations. The current exposure data presented continue to show a wide variation in medical exposures. Also presented are organ doses for four organs (ovaries, testes, thyroid and active bone marrow).

  20. 3D reconstruction based on compressed-sensing (CS)-based framework by using a dental panoramic detector.

    PubMed

    Je, U K; Cho, H M; Hong, D K; Cho, H S; Park, Y O; Park, C K; Kim, K S; Lim, H W; Kim, G A; Park, S Y; Woo, T H; Cho, S I

    2016-01-01

    In this work, we propose a practical method that can combine the two functionalities of dental panoramic and cone-beam CT (CBCT) features in one by using a single panoramic detector. We implemented a CS-based reconstruction algorithm for the proposed method and performed a systematic simulation to demonstrate its viability for 3D dental X-ray imaging. We successfully reconstructed volumetric images of considerably high accuracy by using a panoramic detector having an active area of 198.4 mm × 6.4 mm and evaluated the reconstruction quality as a function of the pitch (p) and the angle step (Δθ). Our simulation results indicate that the CS-based reconstruction almost completely recovered the phantom structures, as in CBCT, for p≤2.0 and θ≤6°, indicating that it seems very promising for accurate image reconstruction even for large-pitch and few-view data. We expect the proposed method to be applicable to developing a cost-effective, volumetric dental X-ray imaging system. PMID:26494155

  1. [How I investigate...the age of adolescents using panoramic radiography].

    PubMed

    Domken, O; Jamoul, C; Piette, P; Legrand, R

    1998-10-01

    Stage of dental development gives an assessment of young adults chronological age. This is used in forensic medicine when birth data are lacking or doubted. The following method improves the accuracy of age determination in comparison with the commonly used method of Nolla. PMID:9857759

  2. Descriptive study of the bifid mandibular canals and retromolar foramina: cone beam CT vs panoramic radiography

    PubMed Central

    Muinelo-Lorenzo, J; Suárez-Quintanilla, J A; Fernández-Alonso, A; Marsillas-Rascado, S

    2014-01-01

    Objectives: To examine the presence and morphologic characteristics of bifid mandibular canals (BMCs) and retromolar foramens (RFs) using cone beam CT (CBCT) and to determine their visualization on panoramic radiographs (PANs). Methods: A sample of 225 CBCT examinations was analysed for the presence of BMCs, as well as length, height, diameter and angle. The diameter of the RF was also determined. Subsequently, corresponding PANs were analysed to determine whether the BMCs and RFs were visible or not. Results: The BMCs were observed on CBCT in 83 out of the 225 patients (36.8%). With respect to gender, statistically significant differences were found in the number of BMCs. There were also significant differences in anatomical characteristics of the types of BMCs. Only 37.8% of the BMCs and 32.5% of the RFs identified on CBCT were also visible on PANs. The diameter had a significant effect on the capability of PANs to visualize BMCs and RFs (B = 0.791, p = 0.035; B = 1.900, p = 0.017, respectively). Conclusions: PANs are unable to sufficiently identify BMCs and RFs. The diameter of these anatomical landmarks represents a relevant factor for visualization on PANs. Pre-operative images using only PANs may lead to underestimation of the presence of BMCs and to surgical complications and anaesthetic failures, which could have been avoided. For true determination of BMCs, a CBCT device should be considered better than a PAN. PMID:24785820

  3. Use of digital panoramic radiography as an auxiliary means of low bone mineral density detection in post-menopausal women

    PubMed Central

    Valerio, C S; Trindade, A M; Mazzieiro, Ê T; Amaral, T P; Manzi, F R

    2013-01-01

    Objectives: To correlate the radiomorphometric indices obtained using digital panoramic radiography (DPR) with bone mineral densities, evaluated by the dual-energy X-ray absorptiometry test, in a population of post-menopausal females to identify patients with asymptomatic low bone mineral densities. Methods: The morphology of the mandibular cortex was evaluated using the mandibular cortical index (MCI) and the inferior mandibular cortex width was evaluated using the mental index (MI) in 64 female patients who had undergone dual-energy X-ray absorptiometry assessment. Of these patients, 21 were diagnosed with osteopaenia and 20 with osteoporosis, and 23 were normal. Three new indices for evaluating the inferior mandibular cortex width were designed: the mental posterior index 1 (MPI1), MPI2 and MPI3. Statistical analyses were performed using the χ2 and Kruskal–Wallis tests and the receiver operating characteristic curve. Results: There were significant differences between the normal and lower bone mineral density groups (osteopaenia and osteoporosis) for MCI (p < 0.01). In the osteoporosis group, the MI, MPI1, MPI2 and MPI3 were significantly different from the normal and osteopaenia groups (p < 0.05). The MI, MPI1, MPI2 and MPI3 showed that there is an area in the mandibular cortex, located between the mental foramen and the antegonial region, which is valid for identifying females at high risk for osteoporosis. Conclusions: The MCI, MI, MPI1, MPI2, and MPI3 radiomorphometric indices evaluated using DPR can be used to identify post-menopausal females with low bone densities and to provide adequate medical treatment for them. PMID:24005062

  4. Toward early diagnosis of arteriosclerotic diseases: collaborative detection of carotid artery calcifications by computer and dentists on dental panoramic radiographs

    NASA Astrophysics Data System (ADS)

    Muramatsu, Chisako; Takahashi, Ryo; Hara, Takeshi; Hayashi, Tatsuro; Katsumata, Akitoshi; Zhou, Xiangrong; Fujita, Hiroshi

    2014-03-01

    Several studies have reported the presence of carotid artery calcifications (CACs) on dental panoramic radiographs (DPRs) as a possible sign of arteriosclerotic diseases. However, CACs are not easily visible at the common window level for dental examinations, and dentists, in general, are not looking for CACs. Computerized detection of CACs may help dentists in referring patients with a risk of arteriosclerotic diseases to have a detailed examination at a medical clinic. Downside of our previous method was a relatively large number of false positives (FPs). In this study, we attempted to reduce FPs by including an additional feature and selecting effective features for the classifier. A hundred DPRs including 34 cases with calcifications were included. Initial candidates were detected by thresholding the output of top-hat operation. For each candidate, 10 features and a new feature characterizing the relative position of a CAC with reference to the lower mandible edge were determined. After the rule-based FP reduction, candidates were classified into CACs and FPs by a support vector machine. Based on the leave-one-out cross-validation evaluations, an average number of FPs was 3.1 per image at 90.4% sensitivity using seven features selected. Compared to our previous method, the number of FPs was reduced by 38% at the same sensitivity level. The proposed method has a potential in identifying patients with a risk of arteriosclerosis early via general dental examinations.

  5. Timing of mineralization of homologues permanent teeth--an evaluation of the dental maturation in panoramic radiographs.

    PubMed

    Sahlstrand, Pia; Lith, Agneta; Hakeberg, Magnus; Norén, Jörgen G

    2013-01-01

    Clinically the condition Molar Incisor Hypomineralization (MIH),varies considerably between individuals, where any number of molars, from one to all four permanent first molars, may be affected with different degrees of hypomineralized enamel within the same dentition. An explanation to these variations could be that the start of the enamel mineralization differs between homologues teeth. The aim of this study was to compare the dental development between homologues teeth in digital panoramic radiographs (PRs),from children aged 7 to 11 years, using the Gleiser & Hunt method on second and third molars and to calculate the crown/root ratio for the mandibular premolars.77 PRs, from individuals between 7.3 and 11.0 years of age, were studied. Differences in developmental stages between homologues teeth (second and third molars) were studied. In 72 of these PRs, the crown/root ratio of mandibular premolars was also compared. In 31 of the PRs, a difference in development was found between the right and left maxillary second molar. In 22 PRs, a difference in development between the right and left mandibular second molar was found. In 17 of the PRs, a difference in development was found between the right and left maxillary third molars. In 26 PRs,a difference in-between the right and left mandibular third molar was found. In 72 PRs, the crown/root ratio of mandibular premolars was measured and differences were found. All these differences were significant. A possible explanation to the variations in expressivity of MIH may be a result of differences in the start of mineralization between homologues teeth. Timing of mineralization of homologues permanent teeth--An evaluation of the dental maturation in panoramic radiographs. PMID:24341164

  6. Continuous measurements of mandibular cortical width on dental panoramic radiographs for computer-aided diagnosis of osteoporosis

    NASA Astrophysics Data System (ADS)

    Kavitha, M. S.; Asano, Akira; Taguchi, Akira

    2011-03-01

    The aim of this study is to develop a computer-aided osteoporosis diagnosis system that automatically determines the inferior cortical width of the mandible continuously on dental panoramic radiographs to realize statistically more robust measurements than the conventional one-point measurements. The cortical width was continuously measured on dental panoramic radiographs by enhancing the original image, determining cortical boundaries, and finally evaluating the distance between boundaries continuously throughout the region of interest. The diagnostic performance using the average width calculated from the continuous measurement was compared with BMD at lumbar spine and femoral neck in 100 postmenopausal women of whom 50 to the development of the tool and 50 to its validation with no history of osteoporosis was evaluated. We experimentally showed the superiority of our method with improved sensitivity and specificity of identifying the development subjects were 90.0% and 75.0% in women with low spinal BMD and 81.8% and 69.2% in those with low femoral BMD, respectively. The corresponding values in the validation subjects were 93.3% and 82.9% at the lumbar spine and 92.3% and 75.7% at the femoral neck, respectively in terms of efficacy for diagnosing osteoporosis. We also assessed the diagnosis and classification of women with osteoporosis using support vector machine employing the average and variance of the continuous measurements gave excellent discrimination ability. It yields sensitivity and specificity of 90.9% and 83.8%, respectively with lumbar spine and 90.0% and 69.1%, respectively with femoral neck BMD. Performance comparison and simplicity of this method indicate that our computeraided system is readily applicable to clinical practice.

  7. Cone beam computed tomography and intraoral radiography for diagnosis of dental abnormalities in dogs and cats

    PubMed Central

    Silva, Luiz Antonio F.; Barriviera, Mauricio; Januário, Alessandro L.; Bezerra, Ana Cristina B.; Fioravanti, Maria Clorinda S.

    2011-01-01

    The development of veterinary dentistry has substantially improved the ability to diagnose canine and feline dental abnormalities. Consequently, examinations previously performed only on humans are now available for small animals, thus improving the diagnostic quality. This has increased the need for technical qualification of veterinary professionals and increased technological investments. This study evaluated the use of cone beam computed tomography and intraoral radiography as complementary exams for diagnosing dental abnormalities in dogs and cats. Cone beam computed tomography was provided faster image acquisition with high image quality, was associated with low ionizing radiation levels, enabled image editing, and reduced the exam duration. Our results showed that radiography was an effective method for dental radiographic examination with low cost and fast execution times, and can be performed during surgical procedures. PMID:22122905

  8. Automatic segmentation of mandible in panoramic x-ray.

    PubMed

    Abdi, Amir Hossein; Kasaei, Shohreh; Mehdizadeh, Mojdeh

    2015-10-01

    As the panoramic x-ray is the most common extraoral radiography in dentistry, segmentation of its anatomical structures facilitates diagnosis and registration of dental records. This study presents a fast and accurate method for automatic segmentation of mandible in panoramic x-rays. In the proposed four-step algorithm, a superior border is extracted through horizontal integral projections. A modified Canny edge detector accompanied by morphological operators extracts the inferior border of the mandible body. The exterior borders of ramuses are extracted through a contour tracing method based on the average model of mandible. The best-matched template is fetched from the atlas of mandibles to complete the contour of left and right processes. The algorithm was tested on a set of 95 panoramic x-rays. Evaluating the results against manual segmentations of three expert dentists showed that the method is robust. It achieved an average performance of [Formula: see text] in Dice similarity, specificity, and sensitivity. PMID:26587551

  9. General Dental Practitioners’ Concept towards Using Radiography and Apex-Locators in Endodontics

    PubMed Central

    Raoof, Maryam; Heidaripour, Maryam; Shahravan, Arash; Haghani, Jahangir; Afkham, Arash; Razifar, Mahsa; Mohammadizadeh, Sakineh

    2014-01-01

    Introduction: Despite being the gold standard as well as a routine technique in endodontics, radiographic working length (WL) determination owns many drawbacks. Electronic apex-locators (EALs) are recommended to complement radiographies. The aim of this study was to evaluate the perceptions of Iranian general dental practitioners (GDPs) towards using radiography and EAL. Methods and Materials: Three hundred and ninety one GDPs attending the 53th Iranian Dental Association Congress completed a questionnaire focusing on the use of radiography and EALs during the various stages of root canal treatment. The data was analyzed with the chi-square test with the level of significance set at 0.05. The results were then calculated as frequencies and percentages. Results: More than half of the GDPs reported using radiographs as the sole method for WL determination. A total of 30.4% of the practitioners were using the combined approach during root canal therapy of a single-rooted tooth, while 38.9% used this method in multi-rooted teeth. Approximately half of the respondents would not order follow-up radiographies after root canal treatment. Conclusion: Radiography continues to be the most common method for WL determination in Iran. PMID:25386209

  10. Clinical utility of dental cone-beam computed tomography: current perspectives

    PubMed Central

    Jaju, Prashant P; Jaju, Sushma P

    2014-01-01

    Panoramic radiography and computed tomography were the pillars of maxillofacial diagnosis. With the advent of cone-beam computed tomography, dental practice has seen a paradigm shift. This review article highlights the potential applications of cone-beam computed tomography in the fields of dental implantology and forensic dentistry, and its limitations in maxillofacial diagnosis. PMID:24729729

  11. Radiography

    NASA Technical Reports Server (NTRS)

    Gardner, C. G.

    1973-01-01

    Radiography is discussed as a method for nondestructive evaluation of internal flaws of solids. Gamma ray and X-ray equipment are described along with radiographic film, radiograph interpretation, and neutron radiography.

  12. Adaptive panoramic tomography with a circular rotational movement for the formation of multifocal image layers

    NASA Astrophysics Data System (ADS)

    Kim, D. S.; Cho, H. S.; Park, Y. O.; Je, U. K.; Hong, D. K.; Choi, S. I.; Koo, Y. S.

    2012-02-01

    Panoramic radiography with which only structures within a certain image layer are in focus and others out of focus on the panoramic image has become a popular imaging technique especially in dentistry. However, the major drawback to the technique is a mismatch between the structures to be focused and the predefined image layer mainly due to the various shapes and sizes of dental arches and/or to malpositioning of the patient. These result in image quality typically inferior to that obtained using intraoral radiographic techniques. In this paper, to overcome these difficulties, we suggest a new panoramic reconstruction algorithm, the so-called adaptive panoramic tomography ( APT), capable of reconstructing multifocal image layers with no additional exposure. In order to verify the effectiveness of the proposed algorithm, we performed systematic simulation studies with a circular rotational movement and investigated the image performance.

  13. A retrospective radiographic evaluation of the anterior loop of the mental nerve: Comparison between panoramic radiography and cone beam computerized tomography

    PubMed Central

    Vujanovic-Eskenazi, Aleksandar; Valero-James, Jesus-Manuel; Sánchez-Garcés, María-Angeles

    2015-01-01

    Objectives: To compare the prevalence and the length of mental loop, measured with panoramic radiography (PR) and cone beam computerized tomography (CBCT). Material and Methods: PG and CBCT images where analyzed by a single calibrated examiner to determine the presence and the position of the mental foramen (MF), its distance to the lower mandible border, the anterior length of the mental loop (ML) and the bone quality in 82 PR and 82 CBCT. Results: ML was identified in 36.6 % of PR and 48.8 % of CBCT. PR showed a magnification of 1.87 when compared to CBCT. The mean of anterior extension of the inferior alveolar nerve and the distance to the inferior border of the mandible was higher for PR (2.8 mm, sd 0.91 mm on the PR , range 1.5 to 4.7 mm and 1.59, sd 0.9 on the CBCT ,range 0.4 to 4.0 mm) Conclusions: There is a magnification in PR images with respect to those of CBCT. The differences between CBCT and PR with regards to the identification and length of the ML are not statistically significant. Identification and accuracy measurements of ML did not depend on the bone quality. Considering that two dimensional imaging provides less accurate and reliable information regarding the anterior loop, a CBCT scan could be recommended when planning implant placement in the anterior region. Key words:Mental loop, mental nerve, mental canal, preoperative implant planning, panoramic tomography, cone beam computerized tomography. PMID:25549693

  14. Characteristics of Medial Depression of the Mandibular Ramus in Patients with Orthodontic Treatment Needs: A Panoramic Radiography Study

    PubMed Central

    B, Naveen Kumar; M.P.V., Prabhat; J., Nalini

    2014-01-01

    Background: Medial sigmoid depression or medial depression of the mandibular ramus (MDMR) is a known variant of the normal radiographic anatomy. The clinical importance of MDMR has been recognized, however, its prevalence and association with patients with orthodontic needs have been poorly documented. Aims and Objectives: To estimate the prevalence and characteristics of MDMR on panoramic radiographs of patients with different Angle’s molar relation. Materials and Methods: Three hundred panoramic radiographs of 100 each belonging to patients with Angle’s class I, II and III molar relationship was recruited from an orthodontic clinic. The radiographs were evaluated for presence of MDMR along with its characteristics such as site and shape. The data was entered in the proforma and subjected for statistical analysis. Results: The overall prevalence of MDMR in the present study was 23.2%. MDMR was found to be more prevalent in Class II – 28 (9.3%) followed by class III-23 (7.6%) and Class I- 19 (6.3%). There was equal distribution of MDMR with respect to site and the semilunar shape was the most common 36 (34%). All these findings were statistically non-significant. Conclusion: Although MDMR is considered as a normal radiographic finding, the present study confirms the disparity in the prevalence of MDMR in patients with dentoskeletal deformities. Thus our findings suggest the importance of recognizing this entity prior to orthognathic surgery so as to avoid untoward sequelas. PMID:25584298

  15. Type and location of findings in dental panoramic tomographs in 7-12-year-old orthodontic patients.

    PubMed

    Pakbaznejad Esmaeili, Elmira; Ekholm, Marja; Haukka, Jari; Waltimo-Sirén, Janna

    2016-05-01

    Objective The Radiation and Nuclear Safety Authority in Finland has paid attention to the large numbers of dental panoramic tomographs (DPTs), particularly in 7-12-year-old children. The majority of these radiographs are taken for orthodontic reasons. Because of the high radiosensitivity of children, the size of the irradiated field should be carefully chosen to yield the necessary diagnostic information at the lowest possible dose. The purpose of the present study was, therefore, to assess the outcome of DPTs within this age group in terms of type and location of pathological findings. It was also hypothesized that DPTs of orthodontic patients rarely display unrestored caries. Materials and methods Four hundred and forty-one DPTs, taken of 7-12-year-old children in 2010-2014, were randomly sampled. The 413 of them (94%) that had been taken for orthodontic reasons were analysed. Results All pathologic findings were restricted to the tooth-bearing area and there was no pathology in the bone structure or any incidental findings in the region of temporomandibular joint. Unlike hypothesized, 27% of the orthodontic DPTs showed caries in deciduous teeth and 16% in permanent teeth. A sub-sample of 229 DPTs, analysed for developmental dental and occlusal problems, most commonly displayed crowding (50%), positional anomalies and local problems with tooth eruption (32%), as well as hyperodontia (15%). Conclusion Inclusion of only the actual area of interest in the image field should be considered case-specifically as a means to reduce the radiation dose. PMID:26634313

  16. Establishment of diagnostic reference levels for dental intraoral radiography.

    PubMed

    Manousaridis, G; Koukorava, C; Hourdakis, C J; Kamenopoulou, V; Yakoumakis, E; Tsiklakis, K

    2013-10-01

    Diagnostic reference levels (DRLs) is a tool for the optimisation of radiological procedures. Establishment of a DRL is a requirement of national regulations. Measurements performed by the Greek Atomic Energy Commission on 529 dental intraoral radiographic facilities have been used in order to define DRLs for digital and film imaging modalities, taking into account the region of the mouth to be imaged. Thus, different DRL values have been proposed for minimum (usually incisors), maximum (usually maxillary molars) and average exposure settings, both for film and digital imaging. The results have been compared with similar studies performed in Europe and the USA and are in line with the most recent ones. PMID:23615358

  17. Relationship Between Femur Bone Mineral Density, Body Mass Index and Dental Panoramic Mandibular Cortical Width in Diagnosis of Elderly Postmenopausal Women With Osteoporosis

    PubMed Central

    Devi B.K., Yashoda; Rakesh, N.; Reddy, Sujatha S.; Santana, N.; Shetty, Naresh

    2014-01-01

    Objectives: To measure and determine mandibular cortical width (MCW) on the panoramic radiographs, to evaluate the usefulness of the method in identifying postmenopausal women with low femoral bone mineral densities (f- BMD) and to correlate the radiographic findings on panoramic radiographs with the f-BMD assessed by dual X-ray absorptiometry (DXA) to predict the efficacy of the radiographic method in diagnosing osteoporosis. Materials and Methods: One hundred and twenty postmenopausal women (60 normal and 60 osteoporotic) in the age group of 50-75 y with f-BMD assessed by DXA had undergone panoramic radiographic examination. The patients were classified as normal (T-score ≥ -1.0) and osteoporotic (T-score ≤ -2.5). MCW on panoramic radiographs was measured bilaterally at the mental foramen region with a caliper and their mean was used as the exposure measure in the analysis. Results: Student t-test showed that mean f-BMD, BMI and MCW was found be less in osteoporotic patients as compared to normal group with a statistically significant p-value < 0.001. Pearson correlation coefficient test revealed that MCW correlated positively with f-BMD and showed a significant decrease with age of the patient. Conclusion: Postmenopausal women with low f-BMD had thinner mandibular cortex at the mental foramen region when compared to normal subjects and are more susceptible to femoral neck fractures. Mandibular inferior cortical width at the mental foramen region could be used to identify postmenopausal women with low f- BMD. Hence, dental panoramic radiographs serve as a useful screening tool for early diagnosis of osteoporotic fractures. PMID:25302265

  18. A Comparison of the Accuracy of Four Age Estimation Methods Based on Panoramic Radiography of Developing Teeth

    PubMed Central

    Javadinejad, Shahrzad; Sekhavati, Hajar; Ghafari, Roshanak

    2015-01-01

    Background and aims. Tooth development is widely used in determining age and state of maturity. Dental age is of high importance in forensic and pediatric dentistry and also orthodontic treatment planning .The aim of this study was to compare the accuracy of four radiographic age estimation methods. Materials and methods. Orthopantomographic images of 537 healthy children (age: 3.9-14.5 years old) were evaluated. Dental age of the subjects was determined through Demirjian’s, Willem’s, Cameriere’s, and Smith’s methods. Differences and correlations between chronological and dental ages were assessed by paired t-tests and Pearson’s correlation analysis, respectively. Results. The mean chronological age of the subjects was 8.93 ± 2.04 years. Overestimations of age were observed following the use of Demirjian’s method (0.87 ± 1.00 years), Willem’s method (0.36 ± 0.87 years), and Smith’s method (0.06 ± 0.63 years). However, Cameriere’s method underestimated age by 0.19 ± 0.86 years. While paired t-tests revealed significant differences between the mean chronological age and ages determined by Demirjian’s, Willem’s, and Cameriere’s methods (P < 0.001), such a significant difference was absent between chronological age and dental age based on Smith’s method (P = 0.079). Pearson’s correlation analysis suggested linear correlations between chronological age and dental age determined by all four methods. Conclusion. Our findings indicated Smith’s method to have the highest accuracy among the four assessed methods. How-ever, all four methods can be used with acceptable accuracy. PMID:26236431

  19. Integrating photo-stimulable phosphor plates into dental and dental hygiene radiography curricula.

    PubMed

    Tax, Cara L; Robb, Christine L; Brillant, Martha G S; Doucette, Heather J

    2013-11-01

    It is not known whether the integration of photo-stimulable phosphor (PSP) plates into dental and dental hygiene curricula creates unique learning challenges for students. The purpose of this two-year study was to determine if dental hygiene students had more and/or different types of errors when using PSP plates compared to film and whether the PSP imaging plates had any particular characteristics that needed to be addressed in the learning process. Fifty-nine first-year dental hygiene students at one Canadian dental school were randomly assigned to two groups (PSP or film) before exposing their initial full mouth series on a teaching manikin using the parallel technique. The principal investigator determined the number and types of errors based on a specific set of performance criteria. The two groups (PSP vs. film) were compared for total number and type of errors made. Results of the study indicated the difference in the total number of errors made using PSP or film was not statistically significant; however, there was a difference in the types of errors made, with the PSP group having more horizontal errors than the film group. In addition, the study identified a number of unique characteristics of the PSP plates that required special consideration for teaching this technology. PMID:24192410

  20. Positioning errors in panoramic images in general dentistry in Sörmland County, Sweden.

    PubMed

    Ekströmer, Karin; Hjalmarsson, Lars

    2014-01-01

    The purpose of this study was to evaluate the frequency and severity of positioning errors in panoramic radiography in general dentistry. A total of 1904 digital panoramic radiographs, taken by the Public Dental Service in the county of Sörmland, Sweden, were analysed retrospectively. The study population consisted of all patients who underwent a panoramic examination during the year 2011. One experienced oral radiologist evaluated all radiographs for 10 common errors. Of the 1904 radiographs examined, 79 per cent had errors. The number of errors varied between 1-4 errors per image. No errors were found in 404 images (21%). Fifty-five images (3%) had severe errors, which made it impossible to make correct diagnostics. The most common error was the tongue not being in contact with the hard palate during exposure. However, this did not greatly affect the diagnostic usefulness of the image due to the ability to enhance the image.The patient's head was tilted too far upwards in 23 per cent of the images and the patient's head was rotated during exposure in 15 per cent. The least common error was due to patient movement during exposure (1%). Panoramic radiographs taken in general dental clinics in a Swedish county show several errors. Proper positioning of the patient is necessary to achieve panoramic images with good image quality. Some of the errors could be adjusted with the digital technique used.This allowed assessment of the images, which reduces radiation dose by avoiding retakes. PMID:26995809

  1. Curricular Guidelines for Clinical Competency by Dental Auxiliaries in Dental Radiography.

    ERIC Educational Resources Information Center

    Journal of Dental Education, 1984

    1984-01-01

    Guidelines developed for educational institutions as curriculum development aids are presented. They are the result of efforts within the American Association of Dental Schools (AADS) by the Section on Oral Radiology. Their use as course development aids is suggested by AADS policy. (MLW)

  2. Effective dose equivalent to the operator in intra-oral dental radiography

    SciTech Connect

    de Haan, R.A.; van Aken, J. )

    1990-08-01

    The effective dose equivalent to the operator in intra-oral dental radiography has been determined. The exposure from a bitewing radiograph and periapical views of the left maxillary incisors and first molar was measured at nine heights and 16 positions, all 1 m from the patient. The effective dose equivalent was determined using data from ICRP 51 (International Commission on Radiological Protection: Data for Use in Protection Against External Radiation). The values presented are related to an exposure of 1 C kg-1 (3876 R) measured free in air at the tube-end. They thus constitute ratios which are not influenced by the sensitivity of the film or other detector used and form standard tables which permit the calculation of the effective dose equivalent in clinical situations.

  3. [Panoramic radiography: why the controversy?].

    PubMed

    Bernhard, M

    1979-03-01

    Because of the confusion which exists between the panography and the orthopantomogram we like to rectify the error. With the orthopantomograph the mandible and the maxilla are taken on a single film. The radiation source is extraoral, whereas for a panography the radiation source is directed from the oral cavity towards the outside, two films are needed, one for each jaw. The orthopantomogram can be used generally in odonto-stomatology. Dosimetry was also mentioned. The results prove that for an orthopantomogram the radiation dose is four times smaller than the dose given for full mouth X-rays taken with 16 intraoral films. It appears that an orthopantomogram should be the first step for a general X-ray examination, though it does not give all informations. For details the intraoral film keeps its value. PMID:293031

  4. Correlation of panoramic radiography and cone beam CT findings in the assessment of the relationship between impacted mandibular third molars and the mandibular canal

    PubMed Central

    Neves, F S; Souza, T C; Almeida, S M; Haiter-Neto, F; Freitas, D Q; Bóscolo, F N

    2012-01-01

    Objectives The aim of this study was to assess the reliability of four panoramic radiographic findings, both individually and in association, in predicting the absence of corticalization between the mandibular canal and the third molar on cone beam CT (CBCT) images. Methods The sample consisted of 72 individuals (142 mandibular third molars) who underwent pre-operative radiographic evaluation before extraction of impacted mandibular third molars. On panoramic radiographs, the most common signs of corticalization (darkening of roots, diversion of mandibular canal, narrowing of mandibular canal and interruption of white line) and the presence or absence of corticalization between the mandibular third molar and the mandibular canal on CBCT images were evaluated. Results Darkening of roots and interruption of white line associated with the absence of corticalization between the mandibular third molar and the mandibular canal on CBCT images were statistically significant, both as isolated findings (p = 0.0001 and p = 0.0006, respectively) and in association (p = 0.002). No statistically significant association was observed for the other panoramic radiographic findings, either individually or in association (p > 0.05). Conclusion Darkening of roots and interruption of white line observed on panoramic radiographs, both as isolated findings and in association, were effective in determining the risk relationship between the tooth roots and the mandibular canal, requiring three-dimensional evaluation of the case. PMID:22282507

  5. [The dental radiograph: pitfalls and surprises].

    PubMed

    Bakx, S; Syriopoulos, K

    2015-05-01

    Guidelines allow retakes of dental radiographs of up to 10%. In the general practice the percentage of retakes is considerably higher. In intraoral radiography film positioning and faults in directing the collimator are the most common reasons for retakes. The use of film holders and correctly aiming the collimator decrease the risk of failure. In panoramic radiography the positioning of the patient in the x-ray machine and the palatoglossal air space are the main causes of failure of radiographs. A systematic approach, a thorough check of the radiation area for artefacts and the use of the available laser lines decrease the risk of a diagnostically unacceptable radiograph. PMID:26210220

  6. Evaluation of dental panoramic radiographic findings in edentulous jaws: A retrospective study of 743 patients "Radiographic features in edentulous jaws"

    PubMed Central

    Kose, Taha Emre; Cakir Karabas, Hulya; Ozcan, Ilknur

    2015-01-01

    PURPOSE The aim of this study was to determine the frequency of significant panoramic radiographic findings and eventual treatment requirements before conventional or implant supported prosthetic treatment in asymptomatic edentulous patients. MATERIALS AND METHODS A total of 743 asymptomatic edentulous patients were retrospectively evaluated using a digital panoramic system. We analyzed the radiographic findings, including impacted teeth, retained root fragments, foreign bodies, severe atrophy of the posterior maxillary alveolar bone, mucous retention cysts, soft tissue calcifications and radiopaque-radiolucent conditions. RESULTS Four-hundred-eighty-seven (65.6%) patients had no radiographic finding. A total of 331 radiographic findings were detected in 256 (34%) patients. In 52.9% (n=175) of these conditions, surgical treatment was required before application of implant-supported fixed prosthesis. However, before application of conventional removable prosthesis surgical treatment was required for 6% (n=20) of these conditions. CONCLUSION The edentulous patients who will have implant placement for implant-supported fixed prosthesis can frequently require additional surgical procedures to eliminate pathological conditions. PMID:26576254

  7. Early prediction of mandibular third molar eruption/impaction using linear and angular measurements on digital panoramic radiography: A radiographic study

    PubMed Central

    Kaur, Rachninder; Kumar, Anand C.; Garg, Ranjana; Sharma, Sugandha; Rastogi, Trisha; Gupta, Vivek Vijay

    2016-01-01

    Background: The impaction rate is higher for the third molars than for any other tooth in modern human population. This study was conducted with the aim to evaluate the validity of linear and angular measurements on the digital panoramic radiograph as a reference for early prediction of mandibular third molar eruption/impaction. Materials and Methods: Digital panoramic radiographs of 200 subjects were selected based on their status of eruption of mandibular third molars; fully erupted (Group A), partially erupted (Group B), fully developed but not erupted (Group C) and partially developed groups (Group D). Each group comprised 50 subjects with 25 males and 25 females. Nine variables (linear measurements, angles, and ratios) were determined and measured bilaterally by two observers and values were compared between the study groups and genders. Results: The data thus obtained were analyzed for comparison among all the study groups. It was found that the difference in the mean values of lower eruption space (LES) measurements, α-angle (angle between long axis of the third molar and gonial-symphyseal plane) and β-angle (angle between long axis of mandibular second and third molars) were significant (P < 0.05). The mean values of mesiodistal width, LES-ramus, LES-Xi point and β-angle were found more in males than in females. No significant difference was observed between the sides. Conclusion: α- and β-angle together with LES measurements give the accurate information on early prediction of lower third molar eruption or impaction. PMID:27433048

  8. Effect of rare earth filtration on patient exposure, dose reduction, and image quality in oral panoramic radiology

    SciTech Connect

    Tyndall, D.A.; Washburn, D.B.

    1987-01-01

    Rare earth intensifying screen material (Gd2O2S:Tb) was added to the standard Al filtration of an oral panoramic x-ray unit, resulting in a beam capable of achieving reductions in patient dose without a loss of image quality. The added rare earth filtration technique resulted in patient dose reductions of 21-56%, depending on anatomic sites, when compared to the conventional Al filtration technique. Films generated from both techniques were measured densitometrically and evaluated by a panel of practicing clinicians. Diagnostically significant differences were minimal. The results indicate that use of rare earth filters in oral panoramic radiography is an effective means of reducing exposures of dental patients to ionizing radiation.

  9. Impact of Digital Panoramic Radiograph Magnification on Vertical Measurement Accuracy

    PubMed Central

    El Hage, Marc; Bernard, Jean-Pierre; Combescure, Christophe; Vazquez, Lydia

    2015-01-01

    Objectives. The purpose of this panoramic radiography study was to assess the impact of image magnification on the accuracy of vertical measurements in the posterior mandible. Methods. Six dental implants, inserted in the posterior segments of a resin model, were used as reference objects. Two observers performed implant length measurements using a proprietary viewer with two preset image magnifications: the low (1.9 : 1) and the medium (3.4 : 1) image magnifications. They also measured the implant lengths in two Digital Imaging Communications in Medicine viewers set at low (1.9 : 1), medium (3.4 : 1), and high (10 : 1) image magnifications. Results. The error between the measured length and the real implant length was close to zero for all three viewers and image magnifications. The percentage of measurements equal to the real implant length was the highest (83.3%) for the high image magnification and below 30% for all viewers with the low image magnification. Conclusions. The high and medium image magnifications used in this study allowed accurate vertical measurements, with all three imaging programs, in the posterior segments of a mandibular model. This study suggests that a low image magnification should not be used for vertical measurements on digital panoramic radiographs when planning an implant in the posterior mandible. PMID:26557851

  10. Relationship of Elongated Styloid Process in Digital Panoramic Radiography with Carotid Intima Thickness and Carotid Atheroma in Doppler Ultrasonography in Osteoporotic Females

    PubMed Central

    Hamedani, Shahram; Dabbaghmanesh, Mohammad Hossein; Zare, Zahra; Hasani, Mahvash; Torabi Ardakani, Mahshid; Hasani, Mahsa; Shahidi, Shoaleh

    2015-01-01

    Statement of the Problem Cardiovascular disease and osteoporosis are major health dilemmas. Osteoporotic patients frequently display vascular calcification that consequently increases the cardiovascular morbidity and mortality. Purpose This study aimed to investigate the relation of osteoporosis, vascular calcification (atheroma, intima-media thickness (IMT)) and elongated styloid process (ESP) in a sample of osteoporotic and normal female individuals. Materials and Method This study recruited 78 women who were assessed for bone mass density (BMD). Sample included individuals with normal BMD (n=13, 17 %), osteopenia (n=36, 46 %), and osteoporosis (n=29, 37%). The presence of atheroma and IMT was examined using color Doppler ultrasonography (CD-US). In addition, digital panoramic radiographs (PRs) were obtained to assess ESP. Results In this study, 55 subjects (70%) with low BMD exhibited at least one side ESP. Femoral BMD decreased significantly in subjects with ESP (p= 0.03). Bilateral ESP was correlated with the presence of atheroma (p= 0.029). The CIMT was greater in patients with ESP, although the relation was not significant. Conclusion The obtained data suggest referring the aged individuals with ESP for BMD assessment and individuals with low bone mass and ESP for more cardiovascular risk assessment. PMID:26046104

  11. Preliminary Evaluation of an Educational Outcomes Assessment Process for Dental Interpretive Radiography.

    ERIC Educational Resources Information Center

    Weems, Richard A.; And Others

    1992-01-01

    A procedure for testing the ability of dental students to detect presence and depth of dental caries was evaluated. Students (n=40) from four experience groups examined radiographs obtained from a model. Results indicated that this method of assessing student competence in radiographic interpretation is valid. (MSE)

  12. Dental x-rays

    MedlinePlus

    X-ray - teeth; Radiograph - dental; Bitewings; Periapical film; Panoramic film ... dentist's office. There are many types of dental x-rays. Some are: Bitewing Periapical Palatal (also called occlusal) ...

  13. A new positioning device for extraoral radiography with conventional dental x-ray machines.

    PubMed

    Schiff, T G; McDavid, W D

    1985-06-01

    Conventional dental periapical x-ray machines are frequently used for taking extraoral radiographs. Such views as the anteroposterior, lateral skull, oblique, Caldwell, Waters, etc. require large focus-to-film distances. A positioning device that makes long-distance positioning easy and foolproof has been developed. This eliminates undesirable repetition and therefore reduces unnecessary exposure of the patient. PMID:3859829

  14. Determining the age of cats by pulp cavity/tooth width ratio using dental radiography

    PubMed Central

    Park, Kyoungsun; Ahn, Jaesang; Kang, Sunmee; Lee, Euiri; Kim, Soohyun; Park, Sangwan; Park, Sungwon; Noh, Hyunwoo

    2014-01-01

    The purpose of this study was to evaluate the effect of age on the ratio of pulp cavity/tooth width (P/T ratio) in healthy cats. The dental radiographs of 32 cats (16 males and 16 females) were generated with a digital dental X-ray unit with the animals under general anesthesia. Standardized measurement of the canine teeth was performed by drawing a line on the radiograph perpendicular to the cementoenamel junction (CEJ) of the tooth. There was an inversely proportional correlation between chronological age and the P/T ratio. Moreover, a strong Pearson squared correlation (γ2 = 0.92) was identified by the curved regression model. No significant differences in the P/T ratio based on gender or breed were found. These results suggest that determination of age by P/T ratio could be clinically useful for estimating the chronological age of cats. PMID:25234207

  15. High-yield radiography of the maxillofacial complex using the free focus and conventional imaging concepts. The resolution performance of nonscreen and screen-film combinations.

    PubMed

    Jensen, T W; Goldberg, A J; Randall, G J

    1983-09-01

    Free focus radiography with miniaturized dental x-ray machines may be a valuable source of "high-yield" diagnostic information in dentistry. This study evaluated the resolution performance of conventional image receptors, including nonscreen and screen-film combinations which were available in sizes suitable for panoramic free focus radiography or conventional extraoral radiography. Results with nonscreen films produced resolution performances ranging from about 10 lp/mm. to about 20 lp/mm. For each film tested, the performances in conventional radiography as well as in free focus radiography with the film in the buccal fold approached the maximum measurable of 20 lp/mm. In a mode of free focus radiography with the film positioned extraorally, there were significant variations in performance according to film brand. A significant reduction in resolution performance occurred when screen-film combinations were tested; resolution ranged between 4.0 lp/mm. and 7.4 lp/mm., with the better performance obtained with free focus radiography. The performance of a rare earth system was similar to other screen-film combinations tested in conventional radiography. In free focus radiography the performance of the rare earth system was slightly below the mean resolution for conventional screen-film combinations at 4.0 lp/mm. and 4.3 lp/mm. An example of a small cassette adapted for intraoral use was given. PMID:6579466

  16. Technique-dependent decrease in thyroid absorbed dose for dental radiography

    SciTech Connect

    Wood, R.E.; Bristow, R.G.; Clark, G.M.; Nussbaum, C.; Taylor, K.W.

    1989-06-01

    A LiF thermoluminescent dosimetry (TLD) system, calibrated in the tissue of interest with the beam used for experimentation, was employed to investigate dosages (muGy) to the thyroid region of an anthropomorphic phantom resultant from two dental complete-mouth radiographic procedures. Both techniques were compared in terms of dosages associated with combinations of lead apron and thyroid collar shielding while using a 70-kVp or 90-kVp x-ray beam for a 20-film complete-mouth series. Lead shielding significantly decreased the dose to the thyroid using both techniques (p less than 0.05). The use of the 90-kVp beam resulted in a significant reduction in the thyroid absorbed dose when using the bisecting angle technique (p less than 0.05) but caused a significant increase in the thyroid absorbed dose when the paralleling technique was used (p less than 0.05). The implementation of higher kilovoltage techniques in dental offices must therefore be dependent on the radiographic technique employed.

  17. Stitched large format CMOS image sensors for dental x-ray digital radiography

    NASA Astrophysics Data System (ADS)

    Liu, Xinqiao (Chiao); Fowler, Boyd; Do, Hung; Jaffe, Mark; Rassel, Richard; Leidy, Bob

    2012-10-01

    In this paper, we present a family of large format CIS's designed for dental x-ray applications. The CIS areas vary from small 31.5mm x 20.1mm, to medium 34.1mm x 26.3mm, to large 37.1mm x 26.3mm. Pixel size is 19.5um x 19.5um. The sensor family was fabricated in a 0.18um CIS process. Stitching is used in the CIS fabrication for the medium and large size sensors. We present the CIS and detector system design that includes pixel circuitry, readout circuitry, x-ray trigger mechanism, scintillator, and the camera electronics. We also present characterization results including the detector performances under both visible light and x-ray radiation.

  18. Dental radiography: tooth enamel EPR dose assessment from Rando phantom measurements

    NASA Astrophysics Data System (ADS)

    Aragno, D.; Fattibene, P.; Onori, S.; Aragno, D.; Fattibene, P.

    2000-09-01

    Electron paramagnetic resonance dosimetry of tooth enamel is now established as a suitable method for individual dose reconstruction following radiation accidents. The accuracy of the method is limited by some confounding factors, among which is the dose received due to medical x-ray irradiation. In the present paper the EPR response of tooth enamel to endoral examination was experimentally evaluated using an anthropomorphic phantom. The dose to enamel for a single exposure of a typical dental examination performed with a new x-ray generation unit working at 65 kVp gave rise to a CO2- signal of intensity similar to that induced by a dose of about 2 mGy of 60Co. EPR measurements were performed on the entire tooth with no attempt to separate buccal and lingual components. Also the dose to enamel for an orthopantomography exam was estimated. It was derived from TLD measurements as equivalent to 0.2 mGy of 60Co. In view of application to risk assessment analysis, in the present work the value for the ratio of the reference dose at the phantom surface measured with TLD to the dose at the tooth measured with EPR was determined.

  19. [A comparison between endoral radiography and electronic magnification of digital orthopantomography].

    PubMed

    Nessi, R; Lazzerini, F; Minorati, D; Blanc, M; Uslenghi, C M

    1995-09-01

    We compared the electronic magnifications obtained from digital panoramic radiographs with intraoral radiographs with a new high resolution film. Fifty-two patients were submitted to both examinations--76 comparative studies and 217 teeth studied in all. The two techniques appeared substantially comparable in terms of diagnostic effectiveness. The measurement of the alveolar ridge was strictly equivalent for the two examinations (< 1 mm disagreement in 80% of cases). The profile of lamina dura and the image of the radicular canal were better depicted with intraoral films. A useful advantage offered by digital images was the possibility of recognizing the soft tissues. In dental caries intraoral films was more effective than digital images and were correctly depicted small carious cavities (< 2 mm depth, 87 vs 74%). Digital panoramic radiography can be considered a promising alternative to panoramic film. Its electronic magnification may be a valuable diagnostic complement to intraoral films for the study of periodontal disease, but it cannot replace intraoral films for the assessment of fine dental details, small caries in particular. The new intraoral film was substantially equivalent to digital images for the assessment of bone lesions and of periodontal disease. PMID:7501826

  20. Accuracy of Panoramic Radiograph in Assessment of the Relationship Between Mandibular Canal and Impacted Third Molars

    PubMed Central

    Tantanapornkul, Weeraya; Mavin, Darika; Prapaiphittayakun, Jaruthai; Phipatboonyarat, Natnicha; Julphantong, Wanchanok

    2016-01-01

    Background: The relationship between impacted mandibular third molar and mandibular canal is important for removal of this tooth. Panoramic radiography is one of the commonly used diagnostic tools for evaluating the relationship of these two structures. Objectives: To evaluate the accuracy of panoramic radiographic findings in predicting direct contact between mandibular canal and impacted third molars on 3D digital images, and to define panoramic criterion in predicting direct contact between the two structures. Methods: Two observers examined panoramic radiographs of 178 patients (256 impacted mandibular third molars). Panoramic findings of interruption of mandibular canal wall, isolated or with darkening of third molar root, diversion of mandibular canal and narrowing of third molar root were evaluated for 3D digital radiography. Direct contact between mandibular canal and impacted third molars on 3D digital images was then correlated with panoramic findings. Panoramic criterion was also defined in predicting direct contact between the two structures. Results: Panoramic findings of interruption of mandibular canal wall, isolated or with darkening of third molar root were statistically significantly correlated with direct contact between mandibular canal and impacted third molars on 3D digital images (p < 0.005), and were defined as panoramic criteria in predicting direct contact between the two structures. Conclusion: Interruption of mandibular canal wall, isolated or with darkening of third molar root observed on panoramic radiographs were effective in predicting direct contact between mandibular canal and impacted third molars on 3D digital images. Panoramic radiography is one of the efficient diagnostic tools for pre-operative assessment of impacted mandibular third molars. PMID:27398105

  1. Cherubism: panoramic and CT features in adults

    PubMed Central

    Redfors, M; Jensen, J L; Storhaug, K; Prescott, T; Larheim, T A

    2013-01-01

    Objectives: To describe the panoramic radiographic and CT features of cherubism in an unselected series of 15 adults. Methods: In this cross-sectional study, 15 individuals aged 29–84 years with familial non-syndromal molecularly confirmed cherubism were examined with panoramic radiography and CT. Bone abnormalities were analysed and described. Results: 11 (73%) of the 15 adults had mandibular abnormalities. These abnormalities ranged from subtly detectable to severe, and were less prevalent and expansive but could be rather similar to the characteristic image features in children. Unilocular radiolucencies were more common than multilocular radiolucencies, and a specific feature of these abnormalities was that they were exclusively found in the anterior mandible. Conclusions: The radiographic and CT abnormalities of cherubism in adults were frequent and extremely heterogeneous, with some distinct features. PMID:24048692

  2. Panoramic lens applications revisited

    NASA Astrophysics Data System (ADS)

    Thibault, Simon

    2008-04-01

    During the last few years, innovative optical design strategies to generate and control image mapping have been successful in producing high-resolution digital imagers and projectors. This new generation of panoramic lenses includes catadioptric panoramic lenses, panoramic annular lenses, visible/IR fisheye lenses, anamorphic wide-angle attachments, and visible/IR panomorph lenses. Given that a wide-angle lens images a large field of view on a limited number of pixels, a systematic pixel-to-angle mapping will help the efficient use of each pixel in the field of view. In this paper, we present several modern applications of these modern types of hemispheric lenses. Recently, surveillance and security applications have been proposed and published in Security and Defence symposium. However, modern hemispheric lens can be used in many other fields. A panoramic imaging sensor contributes most to the perception of the world. Panoramic lenses are now ready to be deployed in many optical solutions. Covered applications include, but are not limited to medical imaging (endoscope, rigiscope, fiberscope...), remote sensing (pipe inspection, crime scene investigation, archeology...), multimedia (hemispheric projector, panoramic image...). Modern panoramic technologies allow simple and efficient digital image processing and the use of standard image analysis features (motion estimation, segmentation, object tracking, pattern recognition) in the complete 360° hemispheric area.

  3. Sensitometric and archival evaluation of Kodak RA films in dental automatic processing.

    PubMed

    Thunthy, K H; Yeadon, W R; Winberg, R

    1994-04-01

    The Kodak Rapid Access System is an extension of the T-grain technology (T-Mat film). Unlike the T-Mat film, the T-Mat/Rapid Access film is forehardened by the addition of more hardener to the film emulsion. It can thus be processed rapidly in a Kodak Rapid Access medical processor in only 45 seconds dry-to-dry cycle by using the Kodak X-Omat RA/30 developer that does not contain a hardener. The absence of the hardener, glutaraldehyde, in the developer also makes this solution environmentally safer. In medical radiography, the T-Mat film has been replaced by the T-Mat/Rapid Access film. However, in dental extraoral radiography the T-Mat film is still being used because the processing solutions and the comparatively low temperatures of dental automatic processors are different from those used in medical radiography. This report shows that, for panoramic and other dental extraoral radiography, T-Mat films can be replaced by T-Mat/RA films by processing them in conventional Kodak X-Omat RP solutions using a dental automatic processing cycle. The differences in the sensitometric properties of the T-Mat and T-Mat/rapid Access films were negligible and therefore clinically insignificant. All films tested well for archival quality. PMID:8015810

  4. Reliability of linear distance measurement for dental implant length with standardized periapical radiographs.

    PubMed

    Wakoh, Mamoru; Harada, Takuya; Otonari, Takamichi; Otonari-Yamamoto, Mika; Ohkubo, Mai; Kousuge, Yuji; Kobayashi, Norio; Mizuta, Shigeru; Kitagawa, Hiromi; Sano, Tsukasa

    2006-08-01

    The purpose of this study was to investigate the accuracy of distance measurements of implant length based on periapical radiographs compared with that of other modalities. We carried out an experimental trial to compare precision in distance measurement. Dental implant fixtures were buried in the canine and first molar regions. These were then subjected to periapical (PE) radiography, panoramic (PA) radiography, conventional (CV) and medical computed (CT) tomography. The length of the implant fixture on each film was measured by nine observers and degree of precision was statistically analyzed. The precision of both PE radiographs and CT tomograms was closest at the highest level. Standardized PE radiography, in particular, was superior to CT tomography in the first molar region. This suggests that standardized PE radiographs should be utilized as a reliable modality for longitudinal and linear distance measurement, depending on implant length at local implantation site. PMID:17344618

  5. A new bite block for panoramic radiographs of anterior edentulous patients: A technical report

    PubMed Central

    Park, Jong-Woong; Symkhampha, Khanthaly; Huh, Kyung-Hoe; Yi, Won-Jin; Lee, Sam-Sun; Choi, Soon-Chul

    2015-01-01

    Purpose Panoramic radiographs taken using conventional chin-support devices have often presented problems with positioning accuracy and reproducibility. The aim of this report was to propose a new bite block for panoramic radiographs of anterior edentulous patients that better addresses these two issues. Materials and Methods A new panoramic radiography bite block similar to the bite block for dentulous patients was developed to enable proper positioning stability for edentulous patients. The new bite block was designed and implemented in light of previous studies. The height of the new bite block was 18 mm and to compensate for the horizontal edentulous space, its horizontal width was 7 mm. The panoramic radiographs using the new bite block were compared with those using the conventional chin-support device. Results Panoramic radiographs taken with the new bite block showed better stability and bilateral symmetry than those taken with the conventional chin-support device. Patients also showed less movement and more stable positioning during panoramic radiography with the new bite block. Conclusion Conventional errors in panoramic radiographs of edentulous patients could be caused by unreliability of the chin-support device. The newly proposed bite block for panoramic radiographs of edentulous patients showed better reliability. Further study is required to evaluate the image quality and reproducibility of images with the new bite block. PMID:26125007

  6. Rotational panoramic radiographs-unusual triple images

    PubMed Central

    Krishnaswamy, Nathamuni-Rengarajan; Tom, Biju; Thavarajah, Rooban

    2015-01-01

    Currently clinicians advice rotational panoramic radiography (RPR) for preliminary investigation. Despite few inherent limitations, rotational panoramic radiography still remains the diagnostic tool of choice. Abnormal structures such as a supernumerary tooth or a device falling within the certain central regions in conventional RPR images may mislead the clinicians towards an inaccurate diagnosis by producing multiple ghost images. Such cases must be treated with circumspect, and apart from RPR, additional imaging modalities need be employed to provide a judicious interpretation of the clinical situation. Thus this manuscript, we present a case where a paramedian supernumerary tooth which exhibited double ghost images on a conventional RPR. This prompted us to elicit the use of a CBCT and 3 dimensional images to determine the true nature of the problem. We outline the working of the diamond principle behind a conventional RPR which cause the appearance of multiple ghost images. The discerning clinician must be cognizant of the possible positional and analytical errors which may be prevalent in a conventional RPR when viewing structures lying in the palatal region, specifically in the midline while making diagnosis. Key words:CBCT, double image, midline supernumerary, OPG. PMID:25810836

  7. Tolerances in panoramic lenses

    NASA Astrophysics Data System (ADS)

    Thibault, Simon; Dallaire, Xavier

    2014-09-01

    Almost every aspect concerning the optical design of panoramic lenses brings new challenges to optical designers. Examples of these include ray tracing programs having problems finding the entrance pupil which is moving through the field-of-view, optimization, production particularities due to the shape of the lenses, and ways of tolerancing these systems having strong distortion. This last topic will be discussed in this paper. We will start from a historical perspective on the understanding of panoramic imagery. This will lead us to the modern panoramic imager called the Panomorph lens. We will discuss the particular case of the tolerance of the front surface (most of the time a freeform surface) and the impact on the image quality, both image footprint and field curvature. We will explain the behavior using first and second order approaches.

  8. Panoramic stereo sphere vision

    NASA Astrophysics Data System (ADS)

    Feng, Weijia; Zhang, Baofeng; Röning, Juha; Zong, Xiaoning; Yi, Tian

    2013-01-01

    Conventional stereo vision systems have a small field of view (FOV) which limits their usefulness for certain applications. While panorama vision is able to "see" in all directions of the observation space, scene depth information is missed because of the mapping from 3D reference coordinates to 2D panoramic image. In this paper, we present an innovative vision system which builds by a special combined fish-eye lenses module, and is capable of producing 3D coordinate information from the whole global observation space and acquiring no blind area 360°×360° panoramic image simultaneously just using single vision equipment with one time static shooting. It is called Panoramic Stereo Sphere Vision (PSSV). We proposed the geometric model, mathematic model and parameters calibration method in this paper. Specifically, video surveillance, robotic autonomous navigation, virtual reality, driving assistance, multiple maneuvering target tracking, automatic mapping of environments and attitude estimation are some of the applications which will benefit from PSSV.

  9. Using the Monte Carlo method for assessing the tissue and organ doses of patients in dental radiography

    NASA Astrophysics Data System (ADS)

    Makarevich, K. O.; Minenko, V. F.; Verenich, K. A.; Kuten, S. A.

    2016-05-01

    This work is dedicated to modeling dental radiographic examinations to assess the absorbed doses of patients and effective doses. For simulating X-ray spectra, the TASMIP empirical model is used. Doses are assessed on the basis of the Monte Carlo method by using MCNP code for voxel phantoms of ICRP. The results of the assessment of doses to individual organs and effective doses for different types of dental examinations and features of X-ray tube are presented.

  10. Effective dose from direct and indirect digital panoramic units

    PubMed Central

    Lee, Gun-Sun; Kim, Jin-Soo; Seo, Yo-Seob

    2013-01-01

    Purpose This study aimed to provide comparative measurements of the effective dose from direct and indirect digital panoramic units according to phantoms and exposure parameters. Materials and Methods Dose measurements were carried out using a head phantom representing an average man (175 cm tall, 73.5 kg male) and a limbless whole body phantom representing an average woman (155 cm tall, 50 kg female). Lithium fluoride thermoluminescent dosimeter (TLD) chips were used for the dosimeter. Two direct and 2 indirect digital panoramic units were evaluated in this study. Effective doses were derived using 2007 International Commission on Radiological Protection (ICRP) recommendations. Results The effective doses of the 4 digital panoramic units ranged between 8.9 µSv and 37.8 µSv. By using the head phantom, the effective doses from the direct digital panoramic units (37.8 µSv, 27.6 µSv) were higher than those from the indirect units (8.9 µSv, 15.9 µSv). The same panoramic unit showed the difference in effective doses according to the gender of the phantom, numbers and locations of TLDs, and kVp. Conclusion To reasonably assess the radiation risk from various dental radiographic units, the effective doses should be obtained with the same numbers and locations of TLDs, and with standard hospital exposure. After that, it is necessary to survey the effective doses from various dental radiographic units according to the gender with the corresponding phantom. PMID:23807930

  11. Wireless networking for the dental office: current wireless standards and security protocols.

    PubMed

    Mupparapu, Muralidhar; Arora, Sarika

    2004-11-15

    Digital radiography has gained immense popularity in dentistry today in spite of the early difficulty for the profession to embrace the technology. The transition from film to digital has been happening at a faster pace in the fields of Orthodontics, Oral Surgery, Endodontics, Periodontics, and other specialties where the radiographic images (periapical, bitewing, panoramic, cephalometric, and skull radiographs) are being acquired digitally, stored within a server locally, and eventually accessed for diagnostic purposes, along with the rest of the patient data via the patient management software (PMS). A review of the literature shows the diagnostic performance of digital radiography is at least comparable to or even better than that of conventional radiography. Similarly, other digital diagnostic tools like caries detectors, cephalometric analysis software, and digital scanners were used for many years for the diagnosis and treatment planning purposes. The introduction of wireless charged-coupled device (CCD) sensors in early 2004 (Schick Technologies, Long Island City, NY) has moved digital radiography a step further into the wireless era. As with any emerging technology, there are concerns that should be looked into before adapting to the wireless environment. Foremost is the network security involved in the installation and usage of these wireless networks. This article deals with the existing standards and choices in wireless technologies that are available for implementation within a contemporary dental office. The network security protocols that protect the patient data and boost the efficiency of modern day dental clinics are enumerated. PMID:15558101

  12. Agreement Between Panoramic and Lateral Cephalometric Radiographs for Measuring the Gonial Angle

    PubMed Central

    Zangouei-Booshehri, Maryam; Aghili, Hossein-Agha; Abasi, Mojtaba; Ezoddini-Ardakani, Fatemeh

    2012-01-01

    Background The gonial angle is one of the most important measurements required for orthodontic treatment and orthognathic surgery. It is difficult to determine the accurate measurement of each gonial angle on cephalometric radiographs because of superimposition of the left and right angles. Objectives The aim of the present study was to determine the right and left gonial angles on panoramic radiographs and to compare them with an evaluated cephalometric sample. Patients and Methods A total of 80 panoramic and 80 cephalometric radiographs were obtained from 6 to 12-year-old children and the gonial angle was determined by the tangent of the inferior border of the mandible and the most distal aspect of the ascending ramus and the condyleon both panoramic and cephalometric radiographs. We used Pearson’s correlation coefficient and paired t-test for comparison. Results The mean gonial angle was 127.07 ± 6.10 and 127.5 ± 6.67 degrees on panoramic and cephalometric radiographs, respectively. There was no statistically significant difference between the measured gonial angles on panoramic and cephalometric radiographs and also no difference between the right and left (both Ps = 0.18) Conclusion The value of the gonial angle measured on panoramic radiography was the same as that measured on the routinely used cephalometric radiography. PMID:23407613

  13. Use of extraoral periapical radiography in Indian population: technique and case reports.

    PubMed

    Kumar, Rahul; Khambete, Neha

    2013-01-01

    Performing intraoral radiography in certain patients is difficult as these patients are unable to tolerate intraoral film placement. To assist such patients a new technique has been innovated using extraoral film placement. Use of this technique has been documented in Caucasian and Taiwanese populations. In this paper we report use of this technique for Indian population. We have done about 40 cases using this technique and have found the average angulation for maxillary (-25+/-5 degrees) and mandibular (-15+/-5 degrees) teeth for Indian population. We recommend use of this technique in the personal dental clinics where panoramic radiographic machines are not readily available. Here we report the technique and cases where diagnostic imaging was performed in patients using the extraoral periapical technique. PMID:23965461

  14. Are Panoramic Radiographs Reliable to Diagnose Mild Alveolar Bone Resorption?

    PubMed Central

    Semenoff, Larissa; Semenoff, Tereza Aparecida Delle; Pedro, Fabio Luiz Miranda; Volpato, Evaristo Ricci; Machado, Maria Aparecida de Andrade Moreira; Borges, Álvaro Henrique; Semenoff-Segundo, Alex

    2011-01-01

    It is extremely important to assess variations between the most used radiographs in dental practice, since minimum distortion on obtained images may change diagnosis, treatment plan, and prognosis for the patient. For this, the distance between the enamel-cementum junction and the alveolar bone crest was measured on conventional and digitized periapical, bitewing, and panoramic radiographs and compared among them. From a total of 1484 records, 39 sets of radiographs that fulfilled the inclusion criteria of the study sample were selected. The measurements were grouped according to the intensity of bone loss. Statistically significant difference was found in the averages of the measurements assessed in radiographs with absence of bone loss between conventional panoramic and periapical radiographs, between digitized panoramic and periapical radiographs and between digitized bitewing and panoramic radiographs. By analyzing the results of this work and considering the research protocol used, one can conclude that small losses in height of alveolar bone crest observed in panoramic radiographs should be cautiously evaluated, as they may be overestimated. PMID:21991470

  15. Are panoramic radiographs reliable to diagnose mild alveolar bone resorption?

    PubMed

    Semenoff, Larissa; Semenoff, Tereza Aparecida Delle; Pedro, Fabio Luiz Miranda; Volpato, Evaristo Ricci; Machado, Maria Aparecida de Andrade Moreira; Borges, Alvaro Henrique; Semenoff-Segundo, Alex

    2011-01-01

    It is extremely important to assess variations between the most used radiographs in dental practice, since minimum distortion on obtained images may change diagnosis, treatment plan, and prognosis for the patient. For this, the distance between the enamel-cementum junction and the alveolar bone crest was measured on conventional and digitized periapical, bitewing, and panoramic radiographs and compared among them. From a total of 1484 records, 39 sets of radiographs that fulfilled the inclusion criteria of the study sample were selected. The measurements were grouped according to the intensity of bone loss. Statistically significant difference was found in the averages of the measurements assessed in radiographs with absence of bone loss between conventional panoramic and periapical radiographs, between digitized panoramic and periapical radiographs and between digitized bitewing and panoramic radiographs. By analyzing the results of this work and considering the research protocol used, one can conclude that small losses in height of alveolar bone crest observed in panoramic radiographs should be cautiously evaluated, as they may be overestimated. PMID:21991470

  16. [Aplication of demineralized human bone matrix in the surgical dental fusion treatment. Report of a case].

    PubMed

    Mora-Rincones, Oscar A; Corona-Rodríguez, Julio C; Díaz-Carvajal, Alvaro L; Franco-Carrero, Isabel C

    2008-06-01

    The purpose of this work is to present a surgical alternative in the treatment of the dental fusions through the placement of demineralized human bone matrix (DHBM) (Grafton Putty)*, immediately after the separation and extraction of the fused tooth to the permanent one. The dental fusion is a dental anomaly of union, that consists in the union of two dental germs during development. It could happen at any of the dental germ evolution stages from the dental sheet or from more advanced processes of differentiation. For the clinical treatment, an allograft of DHBM with osteoinductive and osteoconductive properties was used. This had several factors of bone growth, it allowed the gradual growth of a new bone that helped to correct the bone defects post-extraction and to cover the exposed distal wall of the remaining permanent tooth. The clinic evaluation and the periapical and panoramic radiographies images were used for the clinical control. It can be concluded that the surgical separation and the extraction of the tooth with less anatomical likeness to the contralateral and the placement of the DHBM, represent a surgical treatment alternative of the dental fusion. PMID:18717269

  17. Comparison of the reproducibility of panoramic radiographs between dentulous and edentulous patients

    PubMed Central

    Park, Jong-Woong; Huh, Kyung-Hoe; Yi, Won-Jin; Lee, Sam-Sun; Choi, Soon-Chul

    2014-01-01

    Purpose This study was performed to evaluate the reproducibility of panoramic radiographs of dentulous and edentulous patients. Materials and Methods The reproducibility of panoramic radiographs was evaluated using the panoramic radiographs acquired from 30 anterior dentulous patients by using a common biting positioning device (dentulous group) and 30 anterior edentulous patients by using chin-support devices to take a panoramic radiograph (edentulous group), respectively; these patients had undergone 3 or more panoramic radiographs. The widths and angles between the designated landmarks were measured on the panoramic radiographs, and the reproducibility was evaluated using the intraclass correlation coefficient (ICC) and the coefficient of variation. Results In the dentulous and edentulous groups, the ICCs of the mandibular ramus and mandibular angle areas were higher than the condylar head and zygomatic areas. The mandibular ramus and angle areas showed statistically lower mean coefficients of variation than the condylar head and zygomatic areas in the dentulous group. The mandibular angle area showed a significantly lower mean coefficient of variation than the zygomatic area in the edentulous group. By comparing the two groups, each ICC of the edentulous group was lower than that of the dentulous group, and the mean coefficients of variation of the mandibular ramus area, zygomatic area, left condylar inclination, and ramus ratio between the right and the left in the edentulous group were significantly higher than those in the dentulous group. Conclusion Biting positioning for dentulous patients provided better positioning reproducibility than chin-support positioning when performing panoramic radiography for edentulous patients. PMID:24944958

  18. Digital radiography: an overview.

    PubMed

    Parks, Edwin T; Williamson, Gail F

    2002-11-15

    Since the discovery of X-rays in 1895, film has been the primary medium for capturing, displaying, and storing radiographic images. It is a technology that dental practitioners are the most familiar and comfortable with in terms of technique and interpretation. Digital radiography is the latest advancement in dental imaging and is slowly being adopted by the dental profession. Digital imaging incorporates computer technology in the capture, display, enhancement, and storage of direct radiographic images. Digital imaging offers some distinct advantages over film, but like any emerging technology, it presents new and different challenges for the practitioner to overcome. This article presents an overview of digital imaging including basic terminology and comparisons with film-based imaging. The principles of direct and indirect digital imaging modalities, intraoral and extraoral applications, image processing, and diagnostic efficacy will be discussed. In addition, the article will provide a list of questions dentists should consider prior to purchasing digital imaging systems for their practice. PMID:12444400

  19. Cerebellopontine angle mass mimicking lingual nerve injury after dental implant placement: a case report.

    PubMed

    Momota, Y; Kani, K; Takano, H; Azuma, M

    2015-09-01

    This is a rare case report of a cerebellopontine angle (CPA) mass mimicking lingual nerve injury after a dental implant placement. Lingual nerve injury is a common complication following dental implant placement. CPA masses are likely to cause symptomatic trigeminal neuralgia, and thus can mimic and be easily confused with oral diseases. We experienced a case of CPA mass mimicking lingual nerve injury after dental implant placement. The patient was a 57-year-old Japanese female who complained of glossalgia. She underwent dental implant placement in the mandible before visiting our clinic. Panoramic x-ray radiography revealed no abnormalities; the salivary flow rate by gum test was 7.0 ml/10 min. She was diagnosed with lingual nerve injury and secondary burning mouth syndrome. Vitamin B12 and oral moisturizer did not provide relief; furthermore, numbness in the lower lip emerged. A Semmes Weinstein test demonstrated elevation of her sensitivity threshold. Finally, magnetic resonance imaging revealed a 20-mm diameter mass in the CPA. The patient is now being followed under conservative management. Our experience underscores the importance of including CPA mass in the differential diagnosis of dental diseases. PMID:25280059

  20. Diagnostic quality versus patient exposure with five panoramic screen-film combinations

    SciTech Connect

    D'Ambrosio, J.A.; Schiff, T.G.; McDavid, W.D.; Langland, O.E.

    1986-04-01

    Five film-screen combinations were used to make five density-matched panoramic radiographs of a tissue-equivalent phantom skull using the Midwest/Morita Panoral x-ray machine. The radiographs were evaluated as to their diagnostic quality by twenty dental radiologists. The results demonstrate that proper screen-film selection can significantly reduce patient exposure without compromising diagnostic quality.

  1. Digital panoramic and extraoral imaging.

    PubMed

    Dove, S B; McDavid, W D

    1993-10-01

    Intraoral, panoramic, and extraoral radiographs are the primary means of diagnosing hard-tissue disorders of the dentomaxillofacial region. These imaging methods require the use of x-ray film and subsequent chemical processing to produce diagnostic images. A goal of recent research has been the replacement of this film-based technology with computer-based devices that use electronic or storage phosphor receptors to record the x-ray image in a digital format. This article discusses some of these emerging technologies and their potential effect on the future of panoramic and extraoral radiology. PMID:8224331

  2. Tonsillolith: A Panoramic Radiograph Presentation

    PubMed Central

    Babu B., Balaji; Tejasvi M.L., Avinash; Avinash, C.K. Anulekha; B., Chittaranjan

    2013-01-01

    Tonsilloliths are calcifications within a tonsillar crypt, involve primarily the palatine tonsil caused by dystrophic calcification as a result of chronic inflammation. Tonsilloliths are very uncommon and are microscopic. Tonsillar concretions sometimes produce symptoms which include non-specific chronic halitosis, irritable cough, dysphagia, otalgia and foreign body-like sensation or foul taste. Patients with tonsillolithiasis may also be asymptomatic, with their lesions being discovered incidentally on panoramic radiographs. This article presents an unusual case of multiple bilateral and asymptomatic tonsilloliths which were found during a routine panoramic radiographic examination. PMID:24298535

  3. Panoramic cone beam computed tomography

    SciTech Connect

    Chang Jenghwa; Zhou Lili; Wang Song; Clifford Chao, K. S.

    2012-05-15

    Purpose: Cone-beam computed tomography (CBCT) is the main imaging tool for image-guided radiotherapy but its functionality is limited by a small imaging volume and restricted image position (imaged at the central instead of the treatment position for peripheral lesions to avoid collisions). In this paper, the authors present the concept of ''panoramic CBCT,'' which can image patients at the treatment position with an imaging volume as large as practically needed. Methods: In this novel panoramic CBCT technique, the target is scanned sequentially from multiple view angles. For each view angle, a half scan (180 deg. + {theta}{sub cone} where {theta}{sub cone} is the cone angle) is performed with the imaging panel positioned in any location along the beam path. The panoramic projection images of all views for the same gantry angle are then stitched together with the direct image stitching method (i.e., according to the reported imaging position) and full-fan, half-scan CBCT reconstruction is performed using the stitched projection images. To validate this imaging technique, the authors simulated cone-beam projection images of the Mathematical Cardiac Torso (MCAT) thorax phantom for three panoramic views. Gaps, repeated/missing columns, and different exposure levels were introduced between adjacent views to simulate imperfect image stitching due to uncertainties in imaging position or output fluctuation. A modified simultaneous algebraic reconstruction technique (modified SART) was developed to reconstruct CBCT images directly from the stitched projection images. As a gold standard, full-fan, full-scan (360 deg. gantry rotation) CBCT reconstructions were also performed using projection images of one imaging panel large enough to encompass the target. Contrast-to-noise ratio (CNR) and geometric distortion were evaluated to quantify the quality of reconstructed images. Monte Carlo simulations were performed to evaluate the effect of scattering on the image quality and

  4. Incidental Finding of a Foreign Object on a Panoramic Radiograph.

    PubMed

    Schafer, Tara; Riggs, Bruce; Murakaru, June; Kalathingal, Sajitha

    2015-01-01

    This study's purpose was to describe a case involving the discovery of a foreign body in the ear canal of an eight-year-old boy, revealed during a recall evaluation to a dental clinic. A panoramic radiograph revealed a radiopaque object in the area of the external auditory meatus. The patient's mother reported one incidence of reported ear pain that resolved spontaneously, but the patient denied placing any object into his ear both in our clinic and at the time he reported ear pain to his mother. The patient was referred to an otolaryngologist, and the object was removed. PMID:26531089

  5. Panoramic Imaging and Holographic Interferometry Using a Panoramic Annular Lens.

    NASA Astrophysics Data System (ADS)

    Puliparambil, Joseph Thomas

    1992-01-01

    Ideally, a device for making measurements of the inner surface of a cavity should be rugged, compact, and capable of obtaining an unobstructed, complete, and comprehensive image of the cavity space in every direction. The first attempt to patent a system for panoramic imaging was made by Mangin in 1878 and since that time several other devices have been patented. Most of these devices depend on a scanning system or on a complex set of lenses and mirrors and as such they are not very practical for use. However, in 1984 Dr. Pal Greguss invented a simple lens known as a Panoramic Annular Lens (PAL) capable of giving a full 360 degree surround image of the area around the lens. This lens can be utilized along with digital cameras and computer programs to inspect and measure the interior walls of cavities. If a cavity can be regarded as a cylindrical rather than a spherical volume, the image information can be transformed, using stretching methods, onto a flat surface creating a two-dimensional representation of a three-dimensional cylindrical surface. This phenomenon called Flat Cylindrical Perspective (FCP) forms the basis for the image produced by a PAL. To apply standard methods of analysis on an image and also for visual interpretation, image processing algorithms were developed to linearize a PAL image. These programs can be used for endoscopy which is a technique for imaging the inner part of a volume or cavity. Such techniques have applications in the fields of medicine, civil engineering and aerospace; indeed, anywhere tubes and pipes are involved. Holographic interferometry has become an important diagnostic tool in non-destructive testing, but due to lack of panoramic imaging systems this work could not be effectively used for the analysis of cavities. Now, the PAL can be used for panoramic holographic interferometry which can be used to measure submicron deformations of cavity walls caused by small perturbations in temperature, pressured and mechanical loads

  6. Experiments in interactive panoramic cinema

    NASA Astrophysics Data System (ADS)

    Fisher, Scott S.; Anderson, Steve; Ruiz, Susana; Naimark, Michael; Hoberman, Perry; Bolas, Mark; Weinberg, Richard

    2005-03-01

    For most of the past 100 years, cinema has been the premier medium for defining and expressing relations to the visible world. However, cinematic spectacles delivered in darkened theaters are predicated on a denial of both the body and the physical surroundings of the spectators who are watching it. To overcome these deficiencies, filmmakers have historically turned to narrative, seducing audiences with compelling stories and providing realistic characters with whom to identify. This paper describes several research projects in interactive panoramic cinema that attempt to sidestep the narrative preoccupations of conventional cinema and instead are based on notions of space, movement and embodied spectatorship rather than traditional storytelling. Example projects include interactive works developed with the use of a unique 360 degree camera and editing system, and also development of panoramic imagery for a large projection environment with 14 screens on 3 adjacent walls in a 5-4-5 configuration with observations and findings from an experiment projecting panoramic video on 12 of the 14, in a 4-4-4 270 degree configuration.

  7. Age estimation based on Kvaal's technique using digital panoramic radiographs

    PubMed Central

    Mittal, Samta; Nagendrareddy, Suma Gundareddy; Sharma, Manisha Lakhanpal; Agnihotri, Poornapragna; Chaudhary, Sunil; Dhillon, Manu

    2016-01-01

    Introduction: Age estimation is important for administrative and ethical reasons and also because of legal consequences. Dental pulp undergoes regression in size with increasing age due to secondary dentin deposition and can be used as a parameter of age estimation even beyond 25 years of age. Kvaal et al. developed a method for chronological age estimation based on the pulp size using periapical dental radiographs. There is a need for testing this method of age estimation in the Indian population using simple tools like digital imaging on living individuals not requiring extraction of teeth. Aims and Objectives: Estimation of the chronological age of subjects by Kvaal's method using digital panoramic radiographs and also testing the validity of regression equations as given by Kvaal et al. Materials and Methods: The study sample included a total of 152 subjects in the age group of 14-60 years. Measurements were performed on the standardized digital panoramic radiographs based on Kvaal's method. Different regression formulae were derived and the age was assessed. The assessed age was then correlated to the actual age of the patient using Student's t-test. Results: No significant difference between the mean of the chronological age and the estimated age was observed. However, the values of the mean age estimated by using regression equations as given previously in the study of Kvaal et al. significantly underestimated the chronological age in the present study sample. Conclusion: The results of the study give an inference for the feasibility of this technique by calculation of regression equations on digital panoramic radiographs. However, it negates the applicability of same regression equations as given by Kvaal et al. on the study population.

  8. Digital radiography.

    PubMed

    Mattoon, J S

    2006-01-01

    Digital radiography has been used in human medical imaging since the 1980s with recent and rapid acceptance into the veterinary profession. Using advanced image capture and computer technology, radiographic images are viewed on a computer monitor. This is advantageous because radiographic images can be adjusted using dedicated computer software to maximize diagnostic image quality. Digital images can be accessed at computer workstations throughout the hospital, instantly retrieved from computer archives, and transmitted via the internet for consultation or case referral. Digital radiographic data can also be incorporated into a hospital information system, making record keeping an entirely paperless process. Digital image acquisition is faster when compared to conventional screen-film radiography, improving workflow and patient throughput. Digital radiography greatly reduces the need for 'retake' radiographs because of wide latitude in exposure factors. Also eliminated are costs associated with radiographic film and x-ray film development. Computed radiography, charged coupled devices, and flat panel detectors are types of digital radiography systems currently available. PMID:16971994

  9. [Digital radiography in tomography of the facial bones].

    PubMed

    Ibing, H P; Vogel, H; Biebesheimer, V

    1988-09-01

    In 14 patients the x-ray findings of dental, mandibular and maxillary roentgen diagnosis were compared with conventional tomography and tomography by digital radiography. All details important for diagnosis were shown by both techniques. Tomography by digital radiography offered a more convenient approach and pictures easier to be interpreted than pictures by conventional tomography. PMID:3175474

  10. Effectiveness of the thyroid shield in dental radiology

    SciTech Connect

    Sikorski, P.A.; Taylor, K.W.

    1984-08-01

    The effectiveness of the thyroid shield in reducing patient exposure during routine dental radiographic examinations was studied. A nonscreen film and two film-screen combinations were used as dosimeters and to show the spatial distribution of x-ray exposure. The error in the absolute accuracy of the film dosimeter and the error in the reproducibility of the film-screen combinations were less than +/- 10%. Measurements of thyroid exposure and exposure distribution, with and without the shield, were made on a Rando phantom and on patients. In the phantom study, the reduction by the shield of exposure to the thyroid from primary beam and from scatter was found to be highly dependent on the position of the primary beam relative to the thyroid gland but independent of kVp. Exposure reduction by the shield varied from 5% to 56% for a complete-mouth survey, 2% to 18% for a bitewing survey, and 10% to 79% for a panoramic survey. In the patient study, thyroid skin exposures measured on adults were 33% to 84% lower in offices in which the shield was used as compared to offices in which it was not used. Thyroid skin exposures measured on children were 63% to 92% lower. In accordance with the ALARA principle, these results support the routine use of the thyroid shield for all dental radiography.

  11. Skull Radiography

    MedlinePlus

    What you need to know about… Skull Radiography X-ray images of the skull are taken when it is necessary to see the cranium, facial bones or jaw bones. ... Among other things, x-ray exams of the skull can show fractures. Patient Preparation Before the examination, ...

  12. Endodontic radiography.

    PubMed

    Nixon, P P; Robinson, P B

    1997-05-01

    The ability to take radiographs of good diagnostic quality is an essential prerequisite for successful root canal therapy. However, the operator also has a responsibility to limit the radiation dose to the patient. This article reviews the radiography required for root canal treatment with these criteria in mind. PMID:9515363

  13. A Comparison of Web Page and Slide/Tape for Instruction in Periapical and Panoramic Radiographic Anatomy.

    ERIC Educational Resources Information Center

    Ludlow, John B.; Platin, Enrique

    2000-01-01

    Compared self-guided slide/tape (ST) and Web page (WP) instruction in normal radiographic anatomy of periapical and panoramic images using objective test performance and subjective preferences of 74 freshman dental students. Test performance was not different between image types or presentation technologies, but students preferred WP for…

  14. Performance analysis of panoramic infrared systems

    NASA Astrophysics Data System (ADS)

    Furxhi, Orges; Driggers, Ronald G.; Holst, Gerald; Krapels, Keith

    2014-05-01

    Panoramic imagers are becoming more commonplace in the visible part of the spectrum. These imagers are often used in the real estate market, extreme sports, teleconferencing, and security applications. Infrared panoramic imagers, on the other hand, are not as common and only a few have been demonstrated. A panoramic image can be formed in several ways, using pan and stitch, distributed aperture, or omnidirectional optics. When omnidirectional optics are used, the detected image is a warped view of the world that is mapped on the focal plane array in a donut shape. The final image on the display is the mapping of the omnidirectional donut shape image back to the panoramic world view. In this paper we analyze the performance of uncooled thermal panoramic imagers that use omnidirectional optics, focusing on range performance.

  15. Virtual environments from panoramic images

    NASA Astrophysics Data System (ADS)

    Chapman, David P.; Deacon, Andrew

    1998-12-01

    A number of recent projects have demonstrated the utility of Internet-enabled image databases for the documentation of complex, inaccessible and potentially hazardous environments typically encountered in the petrochemical and nuclear industries. Unfortunately machine vision and image processing techniques have not, to date, enabled the automatic extraction geometrical data from such images and thus 3D CAD modeling remains an expensive and laborious manual activity. Recent developments in panoramic image capture and presentation offer an alternative intermediate deliverable which, in turn, offers some of the benefits of a 3D model at a fraction of the cost. Panoramic image display tools such as Apple's QuickTime VR (QTVR) and Live Spaces RealVR provide compelling and accessible digital representations of the real world and justifiably claim to 'put the reality in Virtual Reality.' This paper will demonstrate how such technologies can be customized, extended and linked to facility management systems delivered over a corporate intra-net to enable end users to become familiar with remote sites and extract simple dimensional data. In addition strategies for the integration of such images with documents gathered from 2D or 3D CAD and Process and Instrumentation Diagrams (P&IDs) will be described as will techniques for precise 'As-Built' modeling using the calibrated images from which panoramas have been derived and the use of textures from these images to increase the realism of rendered scenes. A number of case studies relating to both nuclear and process engineering will demonstrate the extent to which such solution are scaleable in order to deal with the very large volumes of image data required to fully document the large, complex facilities typical of these industry sectors.

  16. Digital Radiography

    NASA Technical Reports Server (NTRS)

    1986-01-01

    System One, a digital radiography system, incorporates a reusable image medium (RIM) which retains an image. No film is needed; the RIM is read with a laser scanner, and the information is used to produce a digital image on an image processor. The image is stored on an optical disc. System allows the radiologist to "dial away" unwanted images to compare views on three screens. It is compatible with existing equipment and cost efficient. It was commercialized by a Stanford researcher from energy selective technology developed under a NASA grant.

  17. Endoscopic measurements using a panoramic annular lens

    NASA Technical Reports Server (NTRS)

    Gilbert, John A.; Matthys, Donald R.

    1992-01-01

    The objective of this project was to design, build, demonstrate, and deliver a prototype system for making measurements within cavities. The system was to utilize structured lighting as the means for making measurements and was to rely on a stationary probe, equipped with a unique panoramic annular lens, to capture a cylindrical view of the illuminated cavity. Panoramic images, acquired with a digitizing camera and stored in a desk top computer, were to be linearized and analyzed by mouse-driven interactive software.

  18. Electron radiography

    SciTech Connect

    Merrill, Frank E.; Morris, Christopher

    2005-05-17

    A system capable of performing radiography using a beam of electrons. Diffuser means receive a beam of electrons and diffuse the electrons before they enter first matching quadrupoles where the diffused electrons are focused prior to the diffused electrons entering an object. First imaging quadrupoles receive the focused diffused electrons after the focused diffused electrons have been scattered by the object for focusing the scattered electrons. Collimator means receive the scattered electrons and remove scattered electrons that have scattered to large angles. Second imaging quadrupoles receive the collimated scattered electrons and refocus the collimated scattered electrons and map the focused collimated scattered electrons to transverse locations on an image plane representative of the electrons' positions in the object.

  19. ZACD: A Retrograde Panoramic Analysis among Indian Population with New System of Classification

    PubMed Central

    Kaur, Prabhpreet; Kaur, Kirandeep

    2016-01-01

    Introduction Zygomatic Air Cell Defect (ZACD) has been considered as a normal radiographic variant with a spare knowledge. This should be judged before any surgical procedure of the temporal region as lack of which can lead to infections of cranium and may other complications. Aim The present study was undertaken to estimate the prevalence and characteristics of ZACD and to propose a classification for the same using digital panoramic radiography. Materials and Methods A total of 6825 digital panoramic radiographs were evaluated retrospectively of subjects aged between 4-90 years from both genders. The radiographs were evaluated by 4 (four) oral radiologists and the ZACD was recorded only when the decision was indisputable. Results Out of 6825 digital panoramic radiographs evaluated ZACD was noticed in 133 subjects with an overall prevalence of 1.94%. A male predilection was noted in the present study with the maximum prevalence during the second, third and fourth decade of life and as the age increases its prevalence decreases. Most commonly it was found to be unilateral and the unilocular presentation being more common. Conclusion Most of the finding of the present study is in acceptance with those conducted previously, but some of the finding contradicts those in the previous ones. It can be because of low sample size of the previous studies. Moreover this study gives a new system to classify these defects to help diagnose the nature of the defect. PMID:26894181

  20. Use of Digital Panoramic Radiographs in the Study of Styloid Process Elongation

    PubMed Central

    Lins, Carla Cabral dos Santos Accioly; Tavares, Renan Macêdo Cutrim; da Silva, Camila Caroline

    2015-01-01

    This work aimed to evaluate the occurrence of suggestive images of styloid process elongation in panoramic radiographs, noting their frequency according to sex, age, and location, as well as measure and classify the types and patterns of calcification of elongated styloid processes. 2,500 panoramic radiographs were evaluated in a Radiology Clinic in Recife, PE, Brazil, performed between 2008 and 2010, with the age ranging from 25 to 80 years old. 560 of the radiographs analyzed fulfilled the inclusion criteria. Of this total, 216 (38.57%) presented suggestive images of the styloid process elongation, 45 (20.8%) belonging to male and 171 (79.2%) to female, and 84.7% were bilateral. After all measurements, mean values of 35.5 mm (left side) and 37.6 mm (right side) were obtained and these differences were statistically significant (p < 0.001). The most common type of stretching found was elongated (type I) with 73.1%, and the pattern of calcification was partially calcified (62.5%). It was found that the elongation of the styloid process is an anatomical variation, which must be taken into account by dentists, and because panoramic radiography is a technique of easy approach and low cost and routine, it can be used to aid in the diagnosis of elongated styloid process. PMID:26290756

  1. Use of Digital Panoramic Radiographs in the Study of Styloid Process Elongation.

    PubMed

    Lins, Carla Cabral Dos Santos Accioly; Tavares, Renan Macêdo Cutrim; da Silva, Camila Caroline

    2015-01-01

    This work aimed to evaluate the occurrence of suggestive images of styloid process elongation in panoramic radiographs, noting their frequency according to sex, age, and location, as well as measure and classify the types and patterns of calcification of elongated styloid processes. 2,500 panoramic radiographs were evaluated in a Radiology Clinic in Recife, PE, Brazil, performed between 2008 and 2010, with the age ranging from 25 to 80 years old. 560 of the radiographs analyzed fulfilled the inclusion criteria. Of this total, 216 (38.57%) presented suggestive images of the styloid process elongation, 45 (20.8%) belonging to male and 171 (79.2%) to female, and 84.7% were bilateral. After all measurements, mean values of 35.5 mm (left side) and 37.6 mm (right side) were obtained and these differences were statistically significant (p < 0.001). The most common type of stretching found was elongated (type I) with 73.1%, and the pattern of calcification was partially calcified (62.5%). It was found that the elongation of the styloid process is an anatomical variation, which must be taken into account by dentists, and because panoramic radiography is a technique of easy approach and low cost and routine, it can be used to aid in the diagnosis of elongated styloid process. PMID:26290756

  2. Panoramic thermal imaging: challenges and tradeoffs

    NASA Astrophysics Data System (ADS)

    Aburmad, Shimon

    2014-06-01

    Over the past decade, we have witnessed a growing demand for electro-optical systems that can provide continuous 3600 coverage. Applications such as perimeter security, autonomous vehicles, and military warning systems are a few of the most common applications for panoramic imaging. There are several different technological approaches for achieving panoramic imaging. Solutions based on rotating elements do not provide continuous coverage as there is a time lag between updates. Continuous panoramic solutions either use "stitched" images from multiple adjacent sensors, or sophisticated optical designs which warp a panoramic view onto a single sensor. When dealing with panoramic imaging in the visible spectrum, high volume production and advancement of semiconductor technology has enabled the use of CMOS/CCD image sensors with a huge number of pixels, small pixel dimensions, and low cost devices. However, in the infrared spectrum, the growth of detector pixel counts, pixel size reduction, and cost reduction is taking place at a slower rate due to the complexity of the technology and limitations caused by the laws of physics. In this work, we will explore the challenges involved in achieving 3600 panoramic thermal imaging, and will analyze aspects such as spatial resolution, FOV, data complexity, FPA utilization, system complexity, coverage and cost of the different solutions. We will provide illustrations, calculations, and tradeoffs between three solutions evaluated by Opgal: A unique 3600 lens design using an LWIR XGA detector, stitching of three adjacent LWIR sensors equipped with a low distortion 1200 lens, and a fisheye lens with a HFOV of 180º and an XGA sensor.

  3. Unusual ghost image in a panoramic radiograph.

    PubMed

    Venkatraman, Sreenivasan; Gowda, J S; Kamarthi, N

    2011-09-01

    A panoramic radiograph was taken for a 9-year-old female patient with her earrings on; thus, artefactual shadows were cast on the radiograph. In addition to the two real images of the earrings, three additional images were seen corresponding to ghost images of the earrings. They were unusual not only in appearance but also because there were three in number. This paper discusses the cause of such images as it revisits the principles of panoramic radiology with respect to ghost images. PMID:21831982

  4. Unusual ghost image in a panoramic radiograph

    PubMed Central

    Venkatraman, S; Gowda, JS; Kamarthi, N

    2011-01-01

    A panoramic radiograph was taken for a 9-year-old female patient with her earrings on; thus, artefactual shadows were cast on the radiograph. In addition to the two real images of the earrings, three additional images were seen corresponding to ghost images of the earrings. They were unusual not only in appearance but also because there were three in number. This paper discusses the cause of such images as it revisits the principles of panoramic radiology with respect to ghost images. PMID:21831982

  5. The effects of image compression on quantitative measurements of digital panoramic radiographs

    PubMed Central

    Apaydın, Burcu; Yılmaz, Hasan-Hüseyin

    2012-01-01

    Objectives: The aims of this study were to explore how image compression affects density, fractal dimension, linear and angular measurements on digital panoramic images and assess inter and intra-observer repeatability of these measurements. Study Design: Sixty-one digital panoramic images in TIFF format (Tagged Image File Format) were compressed to JPEG (Joint Photographic Experts Group) images. Two observers measured gonial angle, antegonial angle, mandibular cortical width, coronal pulp width of maxillary and mandibular first molar, tooth length of maxillary and mandibular first molar on the left side of these images twice. Fractal dimension of the selected regions of interests were calculated and the density of each panoramic radiograph as a whole were also measured on TIFF and JPEG compressed images. Intra-observer and inter-observer consistency was evaluated with Cronbach’s alpha. Paired samples t-test and Kolmogorov-Smirnov test was used to evaluate the difference between the measurements of TIFF and JPEG compressed images. Results: The repeatability of angular measurements had the highest Cronbach’s alpha value (0.997). There was statistically significant difference for both of the observers in mandibular cortical width (MCW) measurements (1st ob. p: 0.002; 2nd ob. p: 0.003), density (p<0.001) and fractal dimension (p<0.001) between TIFF and JPEG images. There was statistically significant difference for the first observer in antegonial angle (1st ob p< 0.001) and maxillary molar coronal pulp width (1st ob. p<0.001) between JPEG and TIFF files. Conclusions: The repeatability of angular measurements is better than linear measurements. Mandibular cortical width, fractal dimension and density are affected from compression. Observer dependent factors might also cause statistically significant differences between the measurements in TIFF and JPEG images. Key words:Digital panoramic radiography, image compression, linear measurements, angular measurements

  6. Study of edge detection task in dental panoramic radiographs.

    PubMed

    Gráfová, L; Kasparová, M; Kakawand, S; Procházka, A; Dostálová, T

    2013-01-01

    The purpose of this study is (1) to introduce a new approach for edge detection in orthopantograms (OPGs) and an improved automatic parameter selector for common edge detectors, (2) to present a comparison between our novel approach with common edge detectors and (3) to provide faster outputs without compromising quality. A new approach for edge detection based on statistical measures was introduced: (1) a set of N edge detection results is calculated from a given input image and a selected type of edge detector, (2) N correspondence maps are constructed from N edge detection results, (3) probabilities and average probabilities are computed, (4) an overall correspondence is evaluated for each correspondence map and (5) the correspondence map providing the best overall correspondence is taken as the result of edge detection procedure. A comparison with common edge detectors (the Roberts, Prewitt, Sobel, Laplacian of the Gaussian and Canny methods) with various parameter settings (304 combinations for each test image) was carried out. The methods were assessed objectively [edge mismatch error (EME), modified Hausdorff distance (MHD) and principal component analysis] and subjectively by experts in dentistry and based on time demands. The suitability of the new approach for edge detection in OPGs was confirmed by experts. The current conventional methods in edge detection in OPGs are inadequate (none of the tested methods reach an EME value or MHD value below 0.1). Our proposed approach for edge detection shows promising potential for its implementation in clinical dentistry. It enhances the accuracy of OPG interpretation and advances diagnosis and treatment planning. PMID:23640989

  7. The implementation of digital sensors in maxillofacial radiography

    NASA Astrophysics Data System (ADS)

    van der Stelt, Paul F.

    2001-03-01

    Systems for intra-oral digital radiography in dentistry can be divided into two main groups: direct sensor systems and semi-direct or indirect sensor systems. Direct imaging is performed by a two-dimensional array of sensor elements. The size of a typical intra-oral CCD-sensor is approximately from 18 mm×24 mm to 30 mm×40 mm; the active area is somewhat smaller, because of the thickness of the packaging of the sensor. CCD-based imaging is now also available for panoramic and cephalometric radiography. Indirect (semi-direct) imaging is based on storage phosphor plates (SPP) imaging. The plate is positioned in the mouth of the patient behind the teeth, and exposed to radiation. The positioning of the sensor plate resembles very much the way conventional radiographic films are handled. SPP technology is also available for panoramic and cephalometric imaging. The purpose of radiography is to provide information to solve a particular diagnostic task. It is therefore very likely that the role of dedicated diagnostic software will become essential in the near future. The importance of dedicated software for diagnostic imaging will increase. As a result of worldwide research, more procedures will become available, for research as well as for use in general practice.

  8. Ultrasound screening for asymptomatic carotid stenosis in subjects with calcifications in the area of the carotid arteries on panoramic radiographs: a cross-sectional study

    PubMed Central

    2011-01-01

    Background Directed ultrasonic screening for carotid stenosis is cost-effective in populations with > 5% prevalence of the diagnosis. Occasionally, calcifications in the area of the carotid arteries are incidentally detected on odontological panoramic radiographs. We aimed to determine if directed screening for carotid stenosis with ultrasound is indicated in individuals with such calcifications. Methods This was a cross-sectional study. Carotid ultrasound examinations were performed on consecutive persons, with findings of calcifications in the area of the carotid arteries on panoramic radiography that were otherwise eligible for asymptomatic carotid endarterectomy. Results Calcification in the area of the carotid arteries was seen in 176 of 1182 persons undergoing panoramic radiography. Of these, 117 fulfilled the inclusion criterion and were examined with carotid ultrasound. Eight persons (6.8%; 95% CI 2.2-11.5%) had a carotid stenosis - not significant over the 5% pre-specified threshold (p = 0.232, Binomial test). However, there was a significant sex difference (p = 0.008), as all stenoses were found in men. Among men, 12.5% (95%CI 4.2-20.8%) had carotid stenosis - significantly over the 5% pre-specified threshold (p = 0.014, Binomial test). Conclusions The incidental finding of calcification in the area of the carotid arteries on panoramic radiographs should be followed up with carotid screening in men that are otherwise eligible for asymptomatic carotid endarterectomy. Trial Registration The study was registered at http://www.clinicaltrials.gov; NCT00514644 PMID:21752238

  9. INDUSTRIAL RADIOGRAPHY INSTRUCTOR'S GUIDE.

    ERIC Educational Resources Information Center

    Bureau of Adult, Vocational, and Technical Education (DHEW/OE), Washington, DC. Div. of Vocational and Technical Education.

    THIS LABORATORY GUIDE WAS DEVELOPED FOR AN 80-HOUR COURSE IN INDUSTRIAL RADIOGRAPHY FOR HIGH SCHOOL GRADUATES TRAINING TO BECOME BEGINNING RADIOGRAPHERS. IT IS USED IN CONJUNCTION WITH TWO OTHER VOLUMES--(1) INDUSTRIAL RADIOGRAPHY INSTRUCTOR'S GUIDE, AND (2) INUDSTRIAL RADIOGRAPHY MANUAL. THE PROGRAM WAS DEVELOPED BY A COMMITTEE OF REPRESENTATIVES…

  10. Mobile Panoramic Video Applications for Learning

    ERIC Educational Resources Information Center

    Multisilta, Jari

    2014-01-01

    The use of videos on the internet has grown significantly in the last few years. For example, Khan Academy has a large collection of educational videos, especially on STEM subjects, available for free on the internet. Professional panoramic video cameras are expensive and usually not easy to carry because of the large size of the equipment.…

  11. Results on Panoramic Spectroscopy of Mrk 171

    NASA Astrophysics Data System (ADS)

    Hakopian, S. A.; Balayan, S. K.; Movsessian, T. A.

    2014-07-01

    Observations of Mrk 171, aimed at conduction of panoramic spectroscopy, were undertaken with the Byurakan 2.6-m telescope using spectrograph ``VAGR''. Within the two components of the galaxy, Mrk171W and Mrk171E, there were differentiated eight condensations of starforming activiity, i.e. HII-regions, and no sign of AGN activity was revealed inspite of existing suggestions.

  12. Reliability of Panoramic Radiographs in the Localization of Mandibular Foramen

    PubMed Central

    Patil, Karthikeya; Guledgud, Mahima V

    2015-01-01

    Objective The present study evaluated the reliability and accuracy of panoramic radiographs in the localization of mandibular foramen. Materials and Methods Twenty five Indian dry human adult mandibles constituted the study material. Ten measurements were carried on each of them to evaluate the location of mandibular foramen with respect to adjacent anatomic landmarks. Panoramic radiographs were then made of the mandibles. Same distances were measured on the traced images of the radiographs. Paired t-test and Pearson’s correlation test were applied to evaluate the accuracy and reliability of panoramic radiographs in localization of mandibular foramen. Results The mean distances measured on dry mandibles and panoramic radiographs showed statistically significant difference (p<0.05). There was strong positive correlation between the measurements on dry mandible and panoramic radiographs. Conclusion The panoramic radiographs can serve as a guide in locating the anterosuperior point of mandibular foramen on panoramic radiographs. PMID:26155559

  13. Dental Amalgam

    MedlinePlus

    ... Products and Medical Procedures Dental Devices Dental Amalgam Dental Amalgam Share Tweet Linkedin Pin it More sharing options Linkedin Pin it Email Print Dental amalgam is a dental filling material which is ...

  14. Correlation of the Radiographic and Morphological Features of the Dental Follicle of Third Molars with Incomplete Root Formation

    PubMed Central

    de OLIVEIRA, David Moraes; de Souza ANDRADE, Emanuel Sávio; da SILVEIRA, Márcia Maria Fonseca; CAMARGO, Igor Batista

    2008-01-01

    The objective of this study was to determine the correlation of the radiographic and morphological features of the dental follicle of unerupted third molars with incomplete root formation. A cross-sectional study was carried out with 56 patients (105 teeth) aged 13 to 24 years. Panoramic radiography was used to determine the stage of root formation to locate and measure pericoronal radiolucency. The width of the dental follicle ranged from 0.0 to 4.0 mm, the distal face being the one most frequently involved, and stage 7 of root formation showing the highest incidence. An inactive enamel reduced epithelium and inactive epithelium remnant also showed a high incidence. Dense connective tissue showed a high incidence, chronic inflammation was infrequent and calcification was a common finding. There was a significant association between the progression of the rhizogenesis and the transformation of the enamel reduced epithelium into a stratified squamous epithelium. No significant association was found between rhizogenesis and the other morphological findings or between the latter and the width of the pericoronal space. It was concluded that there was no clinically significant correlation between the radiographic and morphological features. Every asymptomatic unerupted third molar should be followed up and the follicular tissue analyzed. PMID:18311329

  15. Prevalence of Calcified Carotid Artery on Panoramic Radiographs in Postmenopausal Women

    PubMed Central

    Taheri, Jamileh Beigom; Moshfeghi, Mahkameh

    2009-01-01

    Background and aims This study was designed to evaluate the prevalence of calcified carotid artery in 50 year-old and older postmenopausal dental outpatients for early diagnosis of individuals at risk of stroke. Materials and methods This is a descriptive study of 200 panoramic radiographs. These radiographs included post-menopausal women referring to the Department of Oral Medicine at Shahid Beheshti Faculty of Dentistry during 2006-2007. The x-ray machine, developer and film type were the same for all the radiographs. Statistical analysis included chi-square test and Fisher’s exact test. Results We found 22 calcified carotid arteries. The left and right carotid arteries were involved in 7 and 9 cases, respec-tively. In 6 cases both carotid arteries were calcified. Four individuals had no vascular risk factor excluding age and others had at least one risk factor. We found significant statistical correlation between hypertension, past history of myocardial infarction, and hypercholesterolemia with calcified carotid artery on panoramic radiographs. Conclusion Under the limitations of the present study, prevalence of calcified carotid arteries is 11.0 % in 50 year-old and older postmenopausal dental outpatients. PMID:23230481

  16. The use of radiography in the diagnosis of oral conditions in children and adolescents.

    PubMed

    Fogarty, W P; Drummond, B K; Brosnan, M G

    2015-12-01

    Radiography can serve as a useful aid in the diagnosis of numerous oral conditions, with a place in nearly all of the disciplines of dentistry. As such it can have a beneficial role in caring for the oral health of children and adolescents. The following review discusses the use of radiography in the diagnosis of oral conditions in children and adolescents, with particular reference to the diagnosis of dental caries, dental trauma, growth and development and in other dental scenarios, along with the importance of incidental findings. The risks associated with radiation exposure from the use of radiography are discussed, how these need to be balanced with the possible benefits associated with such use, as well as how risks could be minimised. Summary recommendations are also presented, providing an overview of the use of radiography for oral diagnosis in various clinical scenarios for children and adolescents. PMID:26761981

  17. Free-focus radiography using conventional films: Radiation exposures in a simulated clinical study

    SciTech Connect

    Jensen, T.W.; Randall, G.J.; Goldberg, A.J.

    1980-07-01

    This study compared air exposures during conventional dental and maxillofacial radiography and similar views using free-focus radiography with conventional image receptors. The results show that periapical type surveys on nonscreen film placed extraorally or in the buccal fold may be carried out with an exposure to the surface tissues, which is similar to or less than conventional dental radiography. Extraoral survey type radiographs of the jaws may be carried out with significantly less surface exposure than lateral oblique views of the jaws. The least exposure was required, when the film was placed in the buccla fold instead of against the face during free-focus radiography. The exposures with film screen combinations were reduced by an order of magnitude when compared to the nonscreen techniques. Proper filtration of the beam of the miniaturized x-ray machines radiography in dentistry may thus be desirable and applications in other parts of the body encouraged.

  18. Free-focus radiography using conventional films--radiation exposures in a simulated clinical study.

    PubMed

    Jensen, T W; Randall, G J; Goldberg, A J

    1980-01-01

    This study compared air exposures during conventional dental and maxillofacial radiography and similar views using free-focus radiography with conventional image receptors. The results show that periapical type surveys on nonscreen film placed extraorally or in the buccal fold may be carried out with an exposure to the surface tissues, which is similar to or less than conventional dental radiography. Extraoral survey type radiographs of the jaws may be carried out with significantly less surface exposure than lateral oblique views of the jaws. The least exposure was required, when the film was placed in the buccla fold instead of against the face during free-focus radiography. The exposures with film screen combinations were reduced by an order of magnitude when compared to the nonscreen techniques. Proper filtration of the beam of the miniaturized x-ray machines radiography in dentistry may thus be desirable and applications in other parts of the body encouraged. PMID:7393160

  19. Changes in jawbones of male patients with chronic renal failure on digital panoramic radiographs

    PubMed Central

    Dagistan, Saadettin; Miloglu, Ozkan; Caglayan, Fatma

    2016-01-01

    Objective: To compare the existence of gonial cortical bone thickness, antegonial index, mandibular canal bone resorption and gonial angle values and pathologies like ground-glass appearance in jawbones and brown tumor in male patients undergoing dialysis due to chronic renal failure and men from the healthy control group on panoramic radiographs. Materials and Methods: Panoramic radiographs were taken from 80 male individuals in total (40 normal and 40 dialysis patients). Values obtained from the right and left sides of the mandible were summed and their means were calculated. Gonial cortical thickness, antegonial index and gonial angle values were assessed with the Student's t-test, mandibular canal wall resorption with the Chi-square test, and pathologies such as ground-glass appearance and Brown tumor as “available” or “not available.” Results: Statistically significant differences were observed among the antegonial index (P < 0.001), gonial cortical bone thickness (P < 0.001), and gonial angle (P < 0.001) values of study and control groups. Besides, mandibular canal wall resorption (P < 0.001) was also statistically significant. In the study group, pathologies with ground-glass appearance were encountered in mandible, but no radiographic findings were observed similar to brown tumor. Conclusions: Compared to the control group, decreases were found in gonial cortical bone thicknesses, antegonial index values, mandibular canal wall resorption, and gonial angle values of the patients receiving dialysis treatment due to chronic renal failure. Although it is not statistically significant, pathology with ground-glass appearance was detected in a patient, but no pathologies like brown tumor were observed. These findings from patients with chronic renal failure must be evaluated in panoramic radiography. PMID:27011742

  20. [Metric and angular variables of the mandibular ramus on panoramic radiographs, as indicators for chronologic age].

    PubMed

    Espina-Fereira, Angela; Ortega, Ana Isabel; Barrios, Fernando Alonso; Maldonado, Yadelsy Jackelina; Fereira, José Luis

    2007-12-01

    This paper had as goals to identify the presence of age indicators in the mandibular ramus and to study their applicability in estimating the chronological age of children between the ages of 6 and 12 years. For this, a sample of 128 individuals (70 males and 58 females) was selected, all without chronic or acute sicknesses. An evaluation was made of the metric and angular variables of the mandibular ramus on panoramic radiographs of the oral cavity. The Greulich-Pyle method was applied to estimate the skeletal age, and the Demirjian et al. method was applied to estimate the dental age. A positive correlation, statistically significant, could be observed between the metric variables studied and the chronological age; nevertheless, the angular variables did not show correlation with the chronological age. Regression models were built using metric variables of the mandibular ramus in order to estimate the age, which made a significant contribution to the calculation of the age. A consistent subestimation of the skeletal age and an overestimation of the dental age were found in both sexes. It was evident that a combination of the dental age, the skeletal age and the metric variables obtained in the mandibular ramus, increases the precision for calculating the chronological age, when compared to separate-made estimations of the dental and skeletal age. The proposed regression models can be used for estimating the age of cadavers in advanced states of decomposition and in living individuals without valid identification documents. PMID:18271388

  1. Endoscopic inspection using a panoramic annular lens

    NASA Technical Reports Server (NTRS)

    Gilbert, John A.; Matthys, Donald R.

    1991-01-01

    The objective of this one year study was to design, build, and demonstrate a prototype system for cavity inspection. A cylindrical view of the cavity interior was captured in real time through a compound lens system consisting of a unique panoramic annular lens and a collector lens. Images, acquired with a digitizing camera and stored in a desktop computer, were manipulated using image processing software to aid in visual inspection and qualitative analysis. A detailed description of the lens and its applications is given.

  2. Mars Cameras Make Panoramic Photography a Snap

    NASA Technical Reports Server (NTRS)

    2008-01-01

    If you wish to explore a Martian landscape without leaving your armchair, a few simple clicks around the NASA Web site will lead you to panoramic photographs taken from the Mars Exploration Rovers, Spirit and Opportunity. Many of the technologies that enable this spectacular Mars photography have also inspired advancements in photography here on Earth, including the panoramic camera (Pancam) and its housing assembly, designed by the Jet Propulsion Laboratory and Cornell University for the Mars missions. Mounted atop each rover, the Pancam mast assembly (PMA) can tilt a full 180 degrees and swivel 360 degrees, allowing for a complete, highly detailed view of the Martian landscape. The rover Pancams take small, 1 megapixel (1 million pixel) digital photographs, which are stitched together into large panoramas that sometimes measure 4 by 24 megapixels. The Pancam software performs some image correction and stitching after the photographs are transmitted back to Earth. Different lens filters and a spectrometer also assist scientists in their analyses of infrared radiation from the objects in the photographs. These photographs from Mars spurred developers to begin thinking in terms of larger and higher quality images: super-sized digital pictures, or gigapixels, which are images composed of 1 billion or more pixels. Gigapixel images are more than 200 times the size captured by today s standard 4 megapixel digital camera. Although originally created for the Mars missions, the detail provided by these large photographs allows for many purposes, not all of which are limited to extraterrestrial photography.

  3. Trauma and Mobile Radiography

    SciTech Connect

    Drafke, M.W.

    1989-01-01

    Trauma and Mobile Radiography focuses on the radiography of trauma patients and of patients confined to bed. This book offers students a foundation in the skills they need to produce quality radiograms without causing additional injury or pain to the patient. Features of this new book include: coverage of the basics of radiography and patient care, including monitoring of heavily sedated, immobile, and accident patients. Information on the injuries associated with certain types of accidents, and methods for dealing with these problems. Detailed explanation of the positioning of each anatomical area. A Quick Reference Card with information on evaluating, monitoring and radiographing trauma patients.

  4. Survey of radiographic requirements and techniques in United States dental assisting programs, 1982

    SciTech Connect

    Farman, A.G.; Grammer, S.; Hunter, N.; Baker, C.

    1983-10-01

    A survey of dental assisting programs revealed little standardization of student requirements for dental radiography in the United States. Areas for concern were: the high proportion of programs in which classmates exposed one another to ionizing radiation for training purposes; and the continued use of closed cones in some cases. Preclinical laboratories in radiography were, on average, of considerably longer duration than those previously reported for dental students. Conversely, clinical requirements in intraoral techniques were less for dental assisting students than is the case for dental students. Available methods of reducing patient exposure to ionizing radiation are not being fully implemented.

  5. A Taxonomy of Functions of Dental X-Ray Technologists.

    ERIC Educational Resources Information Center

    Doty, Charles R.; And Others

    The taxonomy of the functions of dental x-ray technologists presented in this report resulted from a dental radiography curriculum development project undertaken at Middlesex County College (MCC) in 1981. After an introductory section citing arguments for creating taxonomies of objectives, the report explains the impetus for the curriculum…

  6. High energy neutron radiography

    SciTech Connect

    Gavron, A.; Morley, K.; Morris, C.; Seestrom, S.; Ullmann, J.; Yates, G.; Zumbro, J.

    1996-06-01

    High-energy spallation neutron sources are now being considered in the US and elsewhere as a replacement for neutron beams produced by reactors. High-energy and high intensity neutron beams, produced by unmoderated spallation sources, open potential new vistas of neutron radiography. The authors discuss the basic advantages and disadvantages of high-energy neutron radiography, and consider some experimental results obtained at the Weapons Neutron Research (WNR) facility at Los Alamos.

  7. Dental Sealants

    MedlinePlus

    ... Data & Statistics > Find Data by Topic > Dental Sealants Dental Sealants Main Content Dental sealants are thin plastic coatings that protect the chewing surfaces of children’s back teeth from tooth decay. Overall, the prevalence of sealants ...

  8. 8. VIEW OF RADIOGRAPHY EQUIPMENT, TEST METHODS INCLUDED RADIOGRAPHY AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. VIEW OF RADIOGRAPHY EQUIPMENT, TEST METHODS INCLUDED RADIOGRAPHY AND BETA BACKSCATTERING. (7/13/56) - Rocky Flats Plant, Non-Nuclear Production Facility, South of Cottonwood Avenue, west of Seventh Avenue & east of Building 460, Golden, Jefferson County, CO

  9. Panoramic view from bluff south of Grand Coulee Dam; this ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Panoramic view from bluff south of Grand Coulee Dam; this segment of the panorama shows the westernmost extend of Franklin D. Roosevelt Lake and part of Grand Coulee Dam, looking north. - Columbia Basin Project, Grand Coulee, Grant County, WA

  10. PANORAMIC VIEW OF SHIPYARD NO. 3, LOOKING SOUTHEAST. FIRST AID ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    PANORAMIC VIEW OF SHIPYARD NO. 3, LOOKING SOUTHEAST. FIRST AID STATION AT CENTER LEFT AND FORGE SHOP AT RIGHT - Rosie the Riveter National Historical Park, Richmond Shipyard No. 3, Point Potrero, Richmond, Contra Costa County, CA

  11. 63. PANORAMIC VIEW OF HEADWORKS FROM WEST SIDE OF RIVER, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    63. PANORAMIC VIEW OF HEADWORKS FROM WEST SIDE OF RIVER, LOOKING UPSTREAM, Prints No. 173, 174 and 175, November 1903 - Electron Hydroelectric Project, Along Puyallup River, Electron, Pierce County, WA

  12. Dental Procedures.

    PubMed

    Ramponi, Denise R

    2016-01-01

    Dental problems are a common complaint in emergency departments in the United States. There are a wide variety of dental issues addressed in emergency department visits such as dental caries, loose teeth, dental trauma, gingival infections, and dry socket syndrome. Review of the most common dental blocks and dental procedures will allow the practitioner the opportunity to make the patient more comfortable and reduce the amount of analgesia the patient will need upon discharge. Familiarity with the dental equipment, tooth, and mouth anatomy will help prepare the practitioner for to perform these dental procedures. PMID:27482994

  13. The Neutron Radiography Reactor (NRAD)

    SciTech Connect

    Imel, G.R.; McClellan, G.C.; Pruett, D.P.

    1990-01-01

    The Neutron Radiography Reactor (NRAD) operated by Argonne National Laboratory is described in this paper. NRAD was designed to allow radiography of highly absorbing reactor fuel assemblies in the vertical position on the routine basis. 7 figs.

  14. Versatile 360-deg panoramic optical system for autonomous robots

    NASA Astrophysics Data System (ADS)

    Barton, George G.; Feldman, Sidney; Beckstead, Jeffrey A.; Nordhauser, Sidney R.

    1999-01-01

    Autonomous mobile robots require wide angle vision for navigation and threat detection and analysis, best served with full panoramic vision. The panoramic optical element is a unique inexpensive first surface reflective aspheric convex cone. This cone can be sized and configured for any vertical FOV desired. The cone acts as a negative optical element generating a panoramic virtual image. When this virtual image is viewed through a standard camera lens it produces at the lenses focal pane a panoramic toroidal image with a translational linearity of > 99 percent. One of three image transducers can be used to convert the toroidal panoramic image to a video signal. Raster scanned CCDs, radially scanned Vidicons and linear CCD arrays on a mechanically rotated state, each have their own particular advantage. Field object distances can be determined in two ways. If the robot is moving the range can be calculated by the size change of a field object versus the distance traversed in a specific time interval. By vertically displacing the panoramic camera by several inches a quasibinocular system is created and the range determined by simple math. Ranging thus produces the third dimension.

  15. 360-deg panoramic camera using a mirror rotation mechanism

    NASA Astrophysics Data System (ADS)

    Nakao, Toshiyasu; Kashitani, Atsushi

    2000-12-01

    In this paper, we describe a new panoramic camera that incorporates a 2-axes mirror rotation mechanism and image mosaicing software to get high-resolution panoramic images in a short time. The mirror is located in front of the camera via the mirror rotation mechanism to move the camera's view. Partial images taken with the mirror rotation are merged into a high-resolution panoramic image by mosaicing software. The 2-axes mirror rotation mechanism consist of a mirror pedestal and a cam. The image mosaicing software projects each partial image onto a projection surface around the rotation center of the mirror. In that process, the projection center is shifted from the original principal point of the lens or the viewpoint to the mirror rotation center, and the projection positions for each pixel of partial images are calculated by using the limiting point. With these features, our panoramic camera has four advantages: (1) accurate, continuous, high-resolution, large and endless (360 degrees wide) panoramic images; (2) short panoramic image acquisition time with fast mirror rotation; (3) small body size; and (4) endless (360 degrees wide) fast mirror rotation. We also describe its prototype and its application to the Internet broadcasting of a tennis game.

  16. A rare syndrome with unusual dental findings: Oculo-facio-cardio-dental syndrome

    PubMed Central

    Verma, Geeta; Singh, Gulshan Kumar; Tandon, Pradeep; Verma, Sneh Late

    2014-01-01

    Radiculomegaly of a tooth is a rare condition. When it is associated with other dental abnormalities, facial dysmorphism and congenital cataracts, the condition is named as oculofaciocardiodental (OFCD) syndrome. This is an X-linked dominant trait, reported only in women, suggesting that it is lethal in males. The most consistent and pathognomic dental finding of OFCD is radiculomegaly (extremely long roots), particularly of the canines and occasionally of other teeth including premolars and incisors, which can easily be diagnosed on dental panoramic radiographs by a dentist or an orthodontist. Till date, 21 cases have been reported worldwide. The aim of this report is to present a new case of a 24 year old female affected by this syndrome and to evaluate it from a dental perspective to call the attention of dentists to this rare anomaly. PMID:25328326

  17. Real-time radiography

    SciTech Connect

    Bossi, R.H.; Oien, C.T.

    1981-02-26

    Real-time radiography is used for imaging both dynamic events and static objects. Fluorescent screens play an important role in converting radiation to light, which is then observed directly or intensified and detected. The radiographic parameters for real-time radiography are similar to conventional film radiography with special emphasis on statistics and magnification. Direct-viewing fluoroscopy uses the human eye as a detector of fluorescent screen light or the light from an intensifier. Remote-viewing systems replace the human observer with a television camera. The remote-viewing systems have many advantages over the direct-viewing conditions such as safety, image enhancement, and the capability to produce permanent records. This report reviews real-time imaging system parameters and components.

  18. Panoramic night vision goggle flight test results

    NASA Astrophysics Data System (ADS)

    Franck, Douglas L.; Geiselman, Eric E.; Craig, Jeffrey L.

    2000-06-01

    The Panoramic Night Vision Goggle (PNVG) has begun operational test and evaluation with its 100-degree horizontal by 40-degree vertical field of view (FOV) on different aircraft and at different locations. Two configurations of the PNVG are being evaluated. The first configuration design (PNVG I) is very low in profile and fits underneath a visor. PNVG I can be retained by the pilot during ejection. This configuration is interchangeable with a day helmet mounted tracker and display through a standard universal connector. The second configuration (PNVG II) resembles the currently fielded 40-degree circular FOV Aviator Night Vision Imaging Systems (ANVIS) and is designed for non-ejection seat aircraft and ground applications. Pilots completed subjective questionnaires after each flight to compare the capability of the 100-degree horizontal by 40-degree vertical PNVG to the 40-degree circular ANVIS across different operational tasks. This paper discusses current findings and pilot feedback from the flight trials objectives of the next phase of the PNVG program are also discussed.

  19. Rank distributions: a panoramic macroscopic outlook.

    PubMed

    Eliazar, Iddo I; Cohen, Morrel H

    2014-01-01

    This paper presents a panoramic macroscopic outlook of rank distributions. We establish a general framework for the analysis of rank distributions, which classifies them into five macroscopic "socioeconomic" states: monarchy, oligarchy-feudalism, criticality, socialism-capitalism, and communism. Oligarchy-feudalism is shown to be characterized by discrete macroscopic rank distributions, and socialism-capitalism is shown to be characterized by continuous macroscopic size distributions. Criticality is a transition state between oligarchy-feudalism and socialism-capitalism, which can manifest allometric scaling with multifractal spectra. Monarchy and communism are extreme forms of oligarchy-feudalism and socialism-capitalism, respectively, in which the intrinsic randomness vanishes. The general framework is applied to three different models of rank distributions-top-down, bottom-up, and global-and unveils each model's macroscopic universality and versatility. The global model yields a macroscopic classification of the generalized Zipf law, an omnipresent form of rank distributions observed across the sciences. An amalgamation of the three models establishes a universal rank-distribution explanation for the macroscopic emergence of a prevalent class of continuous size distributions, ones governed by unimodal densities with both Pareto and inverse-Pareto power-law tails. PMID:24580176

  20. Rank distributions: A panoramic macroscopic outlook

    NASA Astrophysics Data System (ADS)

    Eliazar, Iddo I.; Cohen, Morrel H.

    2014-01-01

    This paper presents a panoramic macroscopic outlook of rank distributions. We establish a general framework for the analysis of rank distributions, which classifies them into five macroscopic "socioeconomic" states: monarchy, oligarchy-feudalism, criticality, socialism-capitalism, and communism. Oligarchy-feudalism is shown to be characterized by discrete macroscopic rank distributions, and socialism-capitalism is shown to be characterized by continuous macroscopic size distributions. Criticality is a transition state between oligarchy-feudalism and socialism-capitalism, which can manifest allometric scaling with multifractal spectra. Monarchy and communism are extreme forms of oligarchy-feudalism and socialism-capitalism, respectively, in which the intrinsic randomness vanishes. The general framework is applied to three different models of rank distributions—top-down, bottom-up, and global—and unveils each model's macroscopic universality and versatility. The global model yields a macroscopic classification of the generalized Zipf law, an omnipresent form of rank distributions observed across the sciences. An amalgamation of the three models establishes a universal rank-distribution explanation for the macroscopic emergence of a prevalent class of continuous size distributions, ones governed by unimodal densities with both Pareto and inverse-Pareto power-law tails.

  1. Flash Proton Radiography

    NASA Astrophysics Data System (ADS)

    Merrill, Frank E.

    Protons were first investigated as radiographic probes as high energy proton accelerators became accessible to the scientific community in the 1960s. Like the initial use of X-rays in the 1800s, protons were shown to be a useful tool for studying the contents of opaque materials, but the electromagnetic charge of the protons opened up a new set of interaction processes which complicated their use. These complications in combination with the high expense of generating protons with energies high enough to penetrate typical objects resulted in proton radiography becoming a novelty, demonstrated at accelerator facilities, but not utilized to their full potential until the 1990s at Los Alamos. During this time Los Alamos National Laboratory was investigating a wide range of options, including X-rays and neutrons, as the next generation of probes to be used for thick object flash radiography. During this process it was realized that the charge nature of the protons, which was the source of the initial difficulty with this idea, could be used to recover this technique. By introducing a magnetic imaging lens downstream of the object to be radiographed, the blur resulting from scattering within the object could be focused out of the measurements, dramatically improving the resolution of proton radiography of thick systems. Imaging systems were quickly developed and combined with the temporal structure of a proton beam generated by a linear accelerator, providing a unique flash radiography capability for measurements at Los Alamos National Laboratory. This technique has now been employed at LANSCE for two decades and has been adopted around the world as the premier flash radiography technique for the study of dynamic material properties.

  2. Electronic system for digital acquisition of rotational panoramic radiographs

    SciTech Connect

    McDavid, W.D.; Dove, S.B.; Welander, U.; Tronje, G. )

    1991-04-01

    A prototype system for digital panoramic imaging of the maxillofacial complex has been developed. In this system x-ray film is replaced by an electronic sensor that delivers the image information to a computer for storage in digital format. The images, which are similar to conventional panoramic radiographs, are displayed on a high-resolution video monitor and may be stored on optical disk for future use. Hard-copy output is also available. The present prototype system has been installed on an Orthopantomograph model OP10 panoramic x-ray machine is programmed for operation with this machine, but in principle the system can be installed on any such device. The system may be incorporated into the design of future panoramic x-ray systems or may be used to retrofit panoramic x-ray systems now using photographic film to record the radiographic image. Greater sensitivity of electronic sensors should make possible a reduction of x-ray dose to the patient, compared with film-based systems.

  3. Digital panoramic polarimeter for remote investigatirn of an optical parameter of celestial bodies

    NASA Astrophysics Data System (ADS)

    Vidmachenko, A. P.; Delec, A. S.; Nevodovskiy, PV.; Andruk, V. M.

    2003-09-01

    Digital panoramic polarimeter is an astronomical television device with panoramic high-sensitivity receiver "superisokone", LI-804 and mechanical block which consist of the polaroid modulator and large rotating achromatic phase-shift plate.

  4. Comparison of the diagnostic accuracy of direct digital radiography system, filtered images, and subtraction radiography

    PubMed Central

    Takeshita, Wilton Mitsunari; Vessoni Iwaki, Lilian Cristina; Da Silva, Mariliani Chicarelli; Filho, Liogi Iwaki; Queiroz, Alfredo De Franco; Geron, Lucas Bachegas Gomes

    2013-01-01

    Background: To compare the diagnostic accuracy of three different imaging systems: Direct digital radiography system (DDR-CMOS), four types of filtered images, and a priori and a posteriori registration of digital subtraction radiography (DSR) in the diagnosis of proximal defects. Materials and Methods: The teeth were arranged in pairs in 10 blocks of vinyl polysiloxane, and proximal defects were performed with drills of 0.25, 0.5, and 1 mm diameter. Kodak RVG 6100 sensor was used to capture the images. A posteriori DSR registrations were done with Regeemy 0.2.43 and subtraction with Image Tool 3.0. Filtered images were obtained with Kodak Dental Imaging 6.1 software. Images (n = 360) were evaluated by three raters, all experts in dental radiology. Results: Sensitivity and specificity of the area under the receiver operator characteristic (ROC) curve (Az) were higher for DSR images with all three drills (Az = 0.896, 0.979, and 1.000 for drills 0.25, 0.5, and 1 mm, respectively). The highest values were found for 1-mm drills and the lowest for 0.25-mm drills, with negative filter having the lowest values of all (Az = 0.631). Conclusion: The best method of diagnosis was by using a DSR. The negative filter obtained the worst results. Larger drills showed the highest sensitivity and specificity values of the area under the ROC curve. PMID:24124300

  5. Apparatus for proton radiography

    DOEpatents

    Martin, Ronald L.

    1976-01-01

    An apparatus for effecting diagnostic proton radiography of patients in hospitals comprises a source of negative hydrogen ions, a synchrotron for accelerating the negative hydrogen ions to a predetermined energy, a plurality of stations for stripping extraction of a radiography beam of protons, means for sweeping the extracted beam to cover a target, and means for measuring the residual range, residual energy, or percentage transmission of protons that pass through the target. The combination of information identifying the position of the beam with information about particles traversing the subject and the back absorber is performed with the aid of a computer to provide a proton radiograph of the subject. In an alternate embodiment of the invention, a back absorber comprises a plurality of scintillators which are coupled to detectors.

  6. Quantitative film radiography

    SciTech Connect

    Devine, G.; Dobie, D.; Fugina, J.; Hernandez, J.; Logan, C.; Mohr, P.; Moss, R.; Schumacher, B.; Updike, E.; Weirup, D.

    1991-02-26

    We have developed a system of quantitative radiography in order to produce quantitative images displaying homogeneity of parts. The materials that we characterize are synthetic composites and may contain important subtle density variations not discernible by examining a raw film x-radiograph. In order to quantitatively interpret film radiographs, it is necessary to digitize, interpret, and display the images. Our integrated system of quantitative radiography displays accurate, high-resolution pseudo-color images in units of density. We characterize approximately 10,000 parts per year in hundreds of different configurations and compositions with this system. This report discusses: the method; film processor monitoring and control; verifying film and processor performance; and correction of scatter effects.

  7. Cosmic Ray Scattering Radiography

    NASA Astrophysics Data System (ADS)

    Morris, C. L.

    2015-12-01

    Cosmic ray muons are ubiquitous, are highly penetrating, and can be used to measure material densities by either measuring the stopping rate or by measuring the scattering of transmitted muons. The Los Alamos team has studied scattering radiography for a number of applications. Some results will be shown of scattering imaging for a range of practical applications, and estimates will be made of the utility of scattering radiography for nondestructive assessments of large structures and for geological surveying. Results of imaging the core of the Toshiba Nuclear Critical Assembly (NCA) Reactor in Kawasaki, Japan and simulations of imaging the damaged cores of the Fukushima nuclear reactors will be presented. Below is an image made using muons of a core configuration for the NCA reactor.

  8. Panoramic Epipolar Image Generation for Mobile Mapping System

    NASA Astrophysics Data System (ADS)

    Chen, T.; Yamamoto, K.; Chhatkuli, S.; Shimamura, H.

    2012-07-01

    The notable improvements on performance and low cost of digital cameras and GPS/IMU devices have caused MMSs (Mobile Mapping Systems) to be gradually becoming one of the most important devices for mapping highway and railway networks, generating and updating road navigation data and constructing urban 3D models over the last 20 years. Moreover, the demands for large scale visual street-level image database construction by the internet giants such as Google and Microsoft have made the further rapid development of this technology. As one of the most important sensors, the omni-directional cameras are being commonly utilized on many MMSs to collect panoramic images for 3D close range photogrammetry and fusion with 3D laser point clouds since these cameras could record much visual information of the real environment in one image at field view angle of 360° in longitude direction and 180° in latitude direction. This paper addresses the problem of panoramic epipolar image generation for 3D modelling and mapping by stereoscopic viewing. These panoramic images are captured with Point Grey's Ladybug3 mounted on the top of Mitsubishi MMS-X 220 at 2m intervals along the streets in urban environment. Onboard GPS/IMU, speedometer and post sequence image analysis technology such as bundle adjustment provided high accuracy position and attitude data for these panoramic images and laser data, this makes it possible to construct the epipolar geometric relationship between any two adjacent panoramic images and then the panoramic epipolar images could be generated. Three kinds of projection planes: sphere, cylinder and flat plane are selected as the epipolar images' planes. In final we select the flat plane and use its effective parts (middle parts of base line's two sides) for epipolar image generation. The corresponding geometric relations and results will be presented in this paper.

  9. Digital radiography in space.

    PubMed

    Hart, Rob; Campbell, Mark R

    2002-06-01

    With the permanent habitation of the International Space Station, the planning of longer duration exploration missions, and the possibility of space tourism, it is likely that digital radiography will be needed in the future to support medical care in space. Ultrasound is currently the medical imaging modality of choice for spaceflight. Digital radiography in space is limited because of prohibitive launch costs (in the region of $20,000/kg) that severely restrict the volume, weight, and power requirements of medical care hardware. Technological increases in radiography, a predicted ten-fold decrease in future launch costs, and an increasing clinical need for definitive medical care in space will drive efforts to expand the ability to provide medical care in space including diagnostic imaging. Normal physiological responses to microgravity, in conjunction with the high-risk environment of spaceflight, increase the risk of injury and could imply an extended recovery period for common injuries. The advantages of gravity on Earth, such as the stabilization of patients undergoing radiography and the drainage of fluids, which provide radiographic contrast, are unavailable in space. This creates significant difficulties in patient immobilization and radiographic positioning. Gravity-dependent radiological signs, such as lipohemarthrosis in knee and shoulder trauma, air or fluid levels in pneumoperitoneum, pleural effusion, or bowel obstruction, and the apical pleural edge in pneumothorax become unavailable. Impaired healing processes such as delayed callus formation following fracture will have implications on imaging, and recovery time lines are unknown. The confined nature of spacecraft and the economic impossibility of launching lead-based personal protective equipment present significant challenges to crew radiation safety. A modified, free-floating radiographic C-arm device equipped with a digital detector and utilizing teleradiology support is proposed as a

  10. Particle Beam Radiography

    NASA Astrophysics Data System (ADS)

    Peach, Ken; Ekdahl, Carl

    2014-02-01

    Particle beam radiography, which uses a variety of particle probes (neutrons, protons, electrons, gammas and potentially other particles) to study the structure of materials and objects noninvasively, is reviewed, largely from an accelerator perspective, although the use of cosmic rays (mainly muons but potentially also high-energy neutrinos) is briefly reviewed. Tomography is a form of radiography which uses multiple views to reconstruct a three-dimensional density map of an object. There is a very wide range of applications of radiography and tomography, from medicine to engineering and security, and advances in instrumentation, specifically the development of electronic detectors, allow rapid analysis of the resultant radiographs. Flash radiography is a diagnostic technique for large high-explosive-driven hydrodynamic experiments that is used at many laboratories. The bremsstrahlung radiation pulse from an intense relativistic electron beam incident onto a high-Z target is the source of these radiographs. The challenge is to provide radiation sources intense enough to penetrate hundreds of g/cm2 of material, in pulses short enough to stop the motion of high-speed hydrodynamic shocks, and with source spots small enough to resolve fine details. The challenge has been met with a wide variety of accelerator technologies, including pulsed-power-driven diodes, air-core pulsed betatrons and high-current linear induction accelerators. Accelerator technology has also evolved to accommodate the experimenters' continuing quest for multiple images in time and space. Linear induction accelerators have had a major role in these advances, especially in providing multiple-time radiographs of the largest hydrodynamic experiments.

  11. Patient care in radiography

    SciTech Connect

    Ehrlich, R.A.; McCloskey, E.D.

    1989-01-01

    This book focuses on patient care procedures for radiographers. The authors focus on the role of the radiographer as a member of the health care team. The authors report on such topics as communication in patient care: safety, medico-legal considerations, transfer and positioning; physical needs; infection control; medication; CPR standards, acute situations; examination of the GI tract; contrast media; special imaging techniques and bedside radiography.

  12. Dental Hygienists

    MedlinePlus

    ... anatomy, patient management, and periodontics, which is the study of gum disease. High school students interested in becoming dental hygienists should take courses in biology, chemistry, and math. Most dental hygiene programs also require applicants to have completed at ...

  13. Dental sealants

    MedlinePlus

    ... this page: //medlineplus.gov/ency/patientinstructions/000779.htm Dental sealants To use the sharing features on this ... case a sealant needs to be replaced. How Dental Sealants Are Applied Your dentist applies sealants on ...

  14. Panoramic dynamic data acquisition system based on unmanned helicopter

    NASA Astrophysics Data System (ADS)

    Yao, Yigang; Zhao, Shuguang; Lin, Zhaorong; Wen, Gaojin; Zhang, Qian; Zhang, Weiwei

    2012-10-01

    In recent years, the archaeological tourism has rapidly been developed all over the world, and it has become more and more popular. However, the scope of the human activities has been restricted by complicated geographical terrain, and the popularization of archaeological tourism has been hampered. For the purpose of solving the above problem, the archaeological tourism system of the panoramic dynamic data acquisition system based on unmanned helicopter is designed, and we got the image of the Chinese Ming Dynasty Great Wall realtime 360˚ panoramic dynamic monitor. The applying of this system will increase the scope of the archaeological tourism activities.

  15. Fringe projection profilometry for panoramic 3D reconstruction

    NASA Astrophysics Data System (ADS)

    Almaraz-Cabral, César-Cruz; Gonzalez-Barbosa, José-Joel; Villa, Jesús; Hurtado-Ramos, Juan-Bautista; Ornelas-Rodriguez, Francisco-Javier; Córdova-Esparza, Diana-Margarita

    2016-03-01

    In this paper, we introduce a panoramic profilometric system to reconstruct inner cylindrical environments. The system projects circular fringes and uses a temporal phase unwrapping technique. The recovered phase map is used to reconstruct objects placed on the inner cylindrical surface. We derived a phase to depth conversion formula for this system. The use of fringe projection allows dense reconstructions. The panoramic system is composed by a digital projector, two parabolic mirrors and a CCD camera. All these components share a common axis with a reference cylinder. This paper presents results for distinct objects.

  16. Dental implants in bilateral bifid canal and compromised interocclusal space using cone beam computerized tomography

    PubMed Central

    Ahmed, Nizar; Arunachalam, Lalitha Tanjore; Jacob, Caroline Annette; Kumar, Suresh Anand

    2016-01-01

    Knowledge of various anatomic landmarks is pivotal for important success. Bifid canals pose a challenge and can lead to difficulties while performing implant surgery in the mandible. Bifid canals can be diagnosed with panoramic radiography and more accurately with cone beam computerized tomography (CBCT). This case report details the placement of the implant in a patient with bilateral bifid canal and compromised interocclusal space, which was successfully treated using CBCT. PMID:27433073

  17. Dental implants in bilateral bifid canal and compromised interocclusal space using cone beam computerized tomography.

    PubMed

    Ahmed, Nizar; Arunachalam, Lalitha Tanjore; Jacob, Caroline Annette; Kumar, Suresh Anand

    2016-01-01

    Knowledge of various anatomic landmarks is pivotal for important success. Bifid canals pose a challenge and can lead to difficulties while performing implant surgery in the mandible. Bifid canals can be diagnosed with panoramic radiography and more accurately with cone beam computerized tomography (CBCT). This case report details the placement of the implant in a patient with bilateral bifid canal and compromised interocclusal space, which was successfully treated using CBCT. PMID:27433073

  18. Regulatory aspects of neutron radiography

    NASA Astrophysics Data System (ADS)

    Hammer, J.

    1999-11-01

    While full legislation for industrial radiography with gamma and X-rays already exists in many countries, the situation is different for neutron radiography. Therefore, the licensing for equipment and procedures in this field has to be based on basic principles of national and international rules. This contribution will explain how the regulatory body in Switzerland deals with neutron radiography installations in order to maintain national standards of health and safety.

  19. Lower Gastrointestinal (GI) Tract X-Ray (Radiography)

    MedlinePlus

    ... Resources Professions Site Index A-Z X-ray (Radiography) - Lower GI Tract Lower gastrointestinal tract radiography or ... Radiography? What is Lower GI Tract X-ray Radiography (Barium Enema)? Lower gastrointestinal (GI) tract radiography, also ...

  20. Dental OCT

    NASA Astrophysics Data System (ADS)

    Colston, Bill W.; Sathyam, Ujwal S.; Dasilva, Luiz B.; Everett, Matthew J.; Stroeve, Pieter; Otis, L. L.

    1998-09-01

    We present here the first in vivo optical coherence tomography (OCT) images of human dental tissue. A novel dental optical coherence tomography system has been developed. This system incorporates the interferometer sample arm and transverse scanning optics into a handpiece that can be used intraorally to image human dental tissues. The average imaging depth of this system varied from 3 mm in hard tissues to 1.5 mm in soft tissues. We discuss the application of this imaging system for dentistry and illustrate the potential of our dental OCT system for diagnosis of periodontal disease, detection of caries, and evaluation of dental restorations.

  1. The Mars NetLander panoramic camera

    NASA Astrophysics Data System (ADS)

    Jaumann, Ralf; Langevin, Yves; Hauber, Ernst; Oberst, Jürgen; Grothues, Hans-Georg; Hoffmann, Harald; Soufflot, Alain; Bertaux, Jean-Loup; Dimarellis, Emmanuel; Mottola, Stefano; Bibring, Jean-Pierre; Neukum, Gerhard; Albertz, Jörg; Masson, Philippe; Pinet, Patrick; Lamy, Philippe; Formisano, Vittorio

    2000-10-01

    The panoramic camera (PanCam) imaging experiment is designed to obtain high-resolution multispectral stereoscopic panoramic images from each of the four Mars NetLander 2005 sites. The main scientific objectives to be addressed by the PanCam experiment are (1) to locate the landing sites and support the NetLander network sciences, (2) to geologically investigate and map the landing sites, and (3) to study the properties of the atmosphere and of variable phenomena. To place in situ measurements at a landing site into a proper regional context, it is necessary to determine the lander orientation on ground and to exactly locate the position of the landing site with respect to the available cartographic database. This is not possible by tracking alone due to the lack of on-ground orientation and the so-called map-tie problem. Images as provided by the PanCam allow to determine accurate tilt and north directions for each lander and to identify the lander locations based on landmarks, which can also be recognized in appropriate orbiter imagery. With this information, it will be further possible to improve the Mars-wide geodetic control point network and the resulting geometric precision of global map products. The major geoscientific objectives of the PanCam lander images are the recognition of surface features like ripples, ridges and troughs, and the identification and characterization of different rock and surface units based on their morphology, distribution, spectral characteristics, and physical properties. The analysis of the PanCam imagery will finally result in the generation of precise map products for each of the landing sites. So far comparative geologic studies of the Martian surface are restricted to the timely separated Mars Pathfinder and the two Viking Lander Missions. Further lander missions are in preparation (Beagle-2, Mars Surveyor 03). NetLander provides the unique opportunity to nearly double the number of accessible landing site data by providing

  2. Measurement accuracy and reliability of tooth length on conventional and CBCT reconstructed panoramic radiographs

    PubMed Central

    Flores-Mir, Carlos; Rosenblatt, Mark R; Major, Paul W.; Carey, Jason P.; Heo, Giseon

    2014-01-01

    INTRODUCTION: This in vivo study assessed accuracy and reliability of tooth length measurements obtained from conventional panoramic radiographs and CBCT panoramic reconstructions to that of a digital caliper (gold standard). METHODS: The sample consisted of subjects who had CBCT and conventional panoramic radiographic imaging and who required maxillary premolar extraction for routine orthodontic treatment. A total of 48 teeth extracted from 26 subjects were measured directly with digital calipers. Radiographic images were scanned and digitally measured in Dolphin 3D software. Accuracy of tooth length measurements made by CBCT panoramic reconstructions, conventional panoramic radiographs and digital caliper (gold standard) were compared to each other by repeated measures one-way ANOVA with Bonferroni correction and by single measures intraclass correlation coefficient. RESULTS: Repeated root length measures with digital calipers, panoramic radiographs and CBCT constructed panoramic-like images were all individually highly reliable. Compared to the caliper (gold standard), tooth measurements obtained from conventional panoramic radiographs were on average 6.3 mm (SD = 2.0 mm) longer, while tooth measurements from CBCT panoramic reconstructions were an average of 1.7 mm (SD = 1.2 mm) shorter. CONCLUSIONS: In comparison to actual tooth lengths, conventional panoramic radiographs were relatively inaccurate, overestimating the lengths by 29%, while CBCT panoramic reconstructions underestimated the lengths by 4%. PMID:25715716

  3. 8. SECOND IMAGE OF THE PANORAMIC SERIES LOOKING WEST FROM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. SECOND IMAGE OF THE PANORAMIC SERIES LOOKING WEST FROM THE UPHILL SIDE OF THE MILL. THE ORE RECEIVING HOUSE AND THE ORE DELIVERY TRESTLE IS IMAGE RIGHT, THE MILL BUILDING AND ANCILLARY STRUCTURE ARE IMAGE CENTER AND THE TOWN OF BODIE IS IMAGE BACKGROUND RIGHT. - Standard Gold Mill, East of Bodie Creek, Northeast of Bodie, Bodie, Mono County, CA

  4. Designing 3 Dimensional Virtual Reality Using Panoramic Image

    NASA Astrophysics Data System (ADS)

    Wan Abd Arif, Wan Norazlinawati; Wan Ahmad, Wan Fatimah; Nordin, Shahrina Md.; Abdullah, Azrai; Sivapalan, Subarna

    The high demand to improve the quality of the presentation in the knowledge sharing field is to compete with rapidly growing technology. The needs for development of technology based learning and training lead to an idea to develop an Oil and Gas Plant Virtual Environment (OGPVE) for the benefit of our future. Panoramic Virtual Reality learning based environment is essential in order to help educators overcome the limitations in traditional technical writing lesson. Virtual reality will help users to understand better by providing the simulations of real-world and hard to reach environment with high degree of realistic experience and interactivity. Thus, in order to create a courseware which will achieve the objective, accurate images of intended scenarios must be acquired. The panorama shows the OGPVE and helps to generate ideas to users on what they have learnt. This paper discusses part of the development in panoramic virtual reality. The important phases for developing successful panoramic image are image acquisition and image stitching or mosaicing. In this paper, the combination of wide field-of-view (FOV) and close up image used in this panoramic development are also discussed.

  5. First of three panoramic views of North Base as seen ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    First of three panoramic views of North Base as seen from top of Building 4500, Control Tower. View looks southwest (220°) at taxiway, hangars, apron, and edge of Rogers Dry Lake. Buildings in distance in left of view are part of Edwards Air Force Base's Main Base. - Edwards Air Force Base, North Base, North Base Road, Boron, Kern County, CA

  6. 60. PANORAMIC VIEW OF DOWNSTREAM FACE. No date, but believed ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    60. PANORAMIC VIEW OF DOWNSTREAM FACE. No date, but believed to be just subsequent to construction. Photograph by C.G. Duffey, Long Beach, California. (38' x 11' framed print). - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

  7. Panoramic view from bluff south of Grand Coulee Dam; this ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Panoramic view from bluff south of Grand Coulee Dam; this segment of the panorama shows the terminus of the concrete-lined feeder canal and entrance to Banks Lake at the head of the Grand Coulee. Note the earthen embankment at the easternmost section of Banks Lake, looking northwest. - Columbia Basin Project, Grand Coulee, Grant County, WA

  8. Motorized Panoramic Camera Mount - Calibration and Image Capture

    NASA Astrophysics Data System (ADS)

    Kauhanen, H.; Rönnholm, P.; Lehtola, V. V.

    2016-06-01

    interesting applications. Among the large variation of panoramic camera systems, we have focused on concentric panoramic imaging with a frame camera. In order to establish the concentric image acquisition, the camera mount must be calibrated so that the projection centre of the camera is located at the rotation centre of the mount. For this purpose, we developed a novel mount calibration method, which allows an accurate recovery of the rotation centre in two image acquisition steps. In addition, we have built a motorized camera mount that can self-calibrate the camera position within the mount, given the previously solved rotation centre, and then be used to automatically capture panoramic images. Hence, we have streamlined the previously laborious manual phase of iterative position calibration, but also automated the capturing of panoramic images. For validation purposes, reference results from a conventional manual mount are provided. In the case of non-motorized mount, the average distance between the projection centre of the camera and the rotation centre of the mount was 0.253 mm and the standard deviation was 0.161 mm. For the motorized mount, the corresponding average distance and standard deviation were 0.549 mm and 0.404 mm, respectively.

  9. Panoramic view from bluff south of Grand Coulee Dam; this ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Panoramic view from bluff south of Grand Coulee Dam; this segment of the panorama shows Crescent Bay Lake (in the foreground), the southern limits of the town of Grand Coulee, and Grand Coulee Dam, looking north. - Columbia Basin Project, Grand Coulee, Grant County, WA

  10. Panoramic view from bluff south of Grand Coulee Dam; this ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Panoramic view from bluff south of Grand Coulee Dam; this segment of the panorama shows the terminus of the concrete-lined feeder canal and entrance to Banks Lake at the head of the Grand Coulee. The southernmost limits of the town of Grand Coulee are seen in the middle. - Columbia Basin Project, Grand Coulee, Grant County, WA

  11. Right panel of panoramic overview of Beaver River Bridge and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Right panel of panoramic overview of Beaver River Bridge and New Brighton, looking SE from Patternson Heights, abuts PA-511-1. - Pittsburgh, Fort Wayne & Chicago Railway, Beaver River Bridge, Spanning Beaver River along line of Second Avenue, New Brighton, Beaver County, PA

  12. Left panel of panoramic overview of Beaver River Bridge and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Left panel of panoramic overview of Beaver River Bridge and New Brighton, looking NE from Patterson Heights, abuts PA-511-2 - Pittsburgh, Fort Wayne & Chicago Railway, Beaver River Bridge, Spanning Beaver River along line of Second Avenue, New Brighton, Beaver County, PA

  13. 2. Photocopy of section of panoramic map of 'Savannah, Georgia ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Photocopy of section of panoramic map of 'Savannah, Georgia 1891' showing Savannah Repair Shops; drawn and published by Augustus Koch, Morning-News Lithograph, Savannah, GA. - Central of Georgia Railway, Savannah Repair Shops & Terminal Facilities, Bounded by West Broad, Jones, West Boundary & Hull Streets, Savannah, Chatham County, GA

  14. 13. TWOSHOT PANORAMIC VIEW OF EAST TERMINAL PIER, GRAIN ELEVATOR, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. TWO-SHOT PANORAMIC VIEW OF EAST TERMINAL PIER, GRAIN ELEVATOR, AND GRAIN GALLERIES AT OFFICIAL OPENING OF TERMINAL, September l, 1922 (Original negative destroyed; print in Barge Canal Construction Photographs, Box 12, Series 501, Accession No. 336-85) - New York Barge Canal, Gowanus Bay Terminal Pier, East of bulkhead supporting Columbia Street, Brooklyn, Kings County, NY

  15. Design of a novel panoramic lens without central blindness

    NASA Astrophysics Data System (ADS)

    Gong, Chen; Cheng, Dewen; Xu, Chen; Wang, Yongtian

    2015-08-01

    The panoramic lenses are getting more and more popular in recent years. However, these lenses have the drawback of obscuring the rays of the coaxial fields, thus cause blind area in the center field of vision. We present a novel panoramic system consisting of two optical channels to overcome this issue, the system has a field of view (FOV) reaching 200 in vertical and 360 in horizontal direction without blindness area. The two channels have different focal lengths, providing design flexibility to meet application requirements where the center FOV or the marginal FOV is of more interest. The system has no half-reflecting surfaces to ensure high transmission ratio, but this feature greatly increase the design difficulty. The distortion of the novel lens is much smaller than traditional panoramic lenses since the distortion has two node points. Due to the ability of information acquisition in real-time and wide-angle, the novel panoramic lens would be very useful for a variety of real-world applications such as surveillance, short-throw projector and pilotless automobile.

  16. Monocular catadioptric panoramic depth estimation via caustics-based virtual scene transition.

    PubMed

    He, Yu; Wang, Lingxue; Cai, Yi; Xue, Wei

    2016-09-01

    Existing catadioptric panoramic depth estimation systems usually require two panoramic imaging subsystems to achieve binocular disparity. The system structures are complicated and only sparse depth maps can be obtained. We present a novel monocular catadioptric panoramic depth estimation method that achieves dense depth maps of panoramic scenes using a single unmodified conventional catadioptric panoramic imaging system. Caustics model the reflection of the curved mirror and establish the distance relationship between the virtual and real panoramic scenes to overcome the nonlinear problem of the curved mirror. Virtual scene depth is then obtained by applying our structure classification regularization to depth from defocus. Finally, real panoramic scene depth is recovered using the distance relationship. Our method's effectiveness is demonstrated in experiments. PMID:27607512

  17. Panoramic radiographic study of mental foramen in selected dravidians of south Indian population: A hospital based study

    PubMed Central

    Gupta, Vaibhav; Pitti, Parag

    2015-01-01

    Background This study aimed at documenting information on appearance, size, horizontal and vertical locations of Mental Foramen (MF) in Panoramic Radiograph. We also analyzed the age and gender differences with radiographic appearance and location of MF. We evaluated these findings in our population and co-relate with results of previous studies. Material and Methods 1662 panoramic radiographs were evaluated, of which 245 fulfilled the inclusion criteria. Each radiograph was traced to record the horizontal and vertical locations. The size of MF was recorded using digital caliper and its appearance was determined by visual examination. Chi-square and t-test were employed. Results The most common appearance of MF was continuous type and the tests showed significant difference with age and gender. The most frequent horizontal location of MF was “location c” with no statistical significant difference with age and gender. The MF was most commonly positioned mesially in relation to the apex of second premolar with no significant differences with gender. The vertical location of the foramen varied drastically with no statistical significant difference in both sides. The difference in dimensions on the left and right sides were not statistically significant. Conclusions Determining the morphological appearance and positional variation of MF is important for isolation of mental nerves and vessels when administering local anesthesia and performing surgeries. We therefore stress the importance of accurate radiographic identification of MF and interpretation. Our research findings can be used as reference material by the dental practitioners of South India while performing clinical procedures that involve MF. Key words:Mental foramen, mental nerve, panoramic radiograph, mandible. PMID:26535088

  18. Comparison of two panoramic front unit arrangements in design of a super wide angle panoramic annular lens.

    PubMed

    Zhou, Xiangdong; Bai, Jian; Wang, Chen; Hou, Xiyun; Wang, Kaiwei

    2016-04-20

    In this paper, a new panoramic annular lens (PAL) with a super wide angle of (30°-120°)×360° is introduced that consists of two parts: a panoramic front unit (PFU) and a relay lens. First, two PFU arrangements referring to the block structured panoramic front unit (BSPFU) and the shell structured panoramic front unit are compared and analyzed in terms of their field curvature correction ability and structural feasibility for obtaining a wide angle PAL. From the comparison, the BSPFU arrangement turns out to be more promising for its good field curvature correction, structure compactness, and convenience for manufacture and assembly. Second, a relay lens composed of six lenses with three Qbfs aspheres has been designed to match the BSPFU. Finally, image performance analysis of the optimized super wide angle PAL is presented. The results show that the designed PAL equipped with a BSPFU and a Qbfs aspherized relay lens achieves good performance under a super wide field of view of (30°-120°)×360°. PMID:27140091

  19. Accuracy of direct digital radiography for detecting occlusal caries in primary teeth compared with conventional radiography and visual inspection: an in vitro study

    PubMed Central

    Dias da Silva, P R; Martins Marques, M; Steagall, W; Medeiros Mendes, F; Lascala, C A

    2010-01-01

    Objectives The diagnosis of caries lesions is still a matter of concern in dentistry. The diagnosis of dental caries by digital radiography has a number of advantages over conventional radiography; however, this method has not been explored fully in the field of paediatric dentistry. This in vitro research evaluated the accuracy of direct digital radiography compared with visual inspection and conventional radiography in the diagnosis of occlusal caries lesions in primary molars. Methods 50 molars were selected and evaluated under standardized conditions by 2 previously calibrated examiners according to 3 diagnostic methods (visual inspection, conventional radiography and direct digital radiography). Direct digital radiographs were obtained with the Dixi3 system (Planmeca, Helsinki, Finland) and the conventional radiographs with InSight film (Kodak Eastman Co., Rochester, NY). The images were scored and a reference standard was obtained histologically. The interexaminer reliability was calculated using Cohen's kappa test and the specificity, sensitivity and accuracy of the methods were calculated. Results Examiner reliability was good. For lesions limited to the enamel, visual inspection showed significantly higher sensitivity and accuracy than both radiographic methods, but no significant difference was found in specificity. For teeth with dentinal caries, no significant differences were found for any parameter when comparing visual and radiographic evaluation. Conclusions Although less accurate than the visual method for detecting caries lesions confined to the enamel, the direct digital radiographic method is as effective as conventional radiographic examination and visual inspection of primary teeth with occlusal caries when the dentine is involved. PMID:20729186

  20. Scatter in Cargo Radiography

    SciTech Connect

    Erin A. Miller; Joseph A. Caggiano; Robert C. Runkle; Timothy A. White; Aaron M. Bevill

    2011-03-01

    As a complement to passive detection systems, radiographic inspection of cargo is an increasingly important tool for homeland security because it has the potential to detect highly attenuating objects associated with special nuclear material or surrounding shielding, in addition to screening for items such as drugs or contraband. Radiographic detection of such threat objects relies on high image contrast between regions of different density and atomic number (Z). Threat detection is affected by scatter of the interrogating beamin the cargo, the radiographic system itself, and the surrounding environment, which degrades image contrast. Here, we estimate the extent to which scatter plays a role in radiographic imaging of cargo containers. Stochastic transport simulations were performed to determine the details of the radiography equipment and surrounding environment, which are important in reproducing measured data and to investigate scatter magnitudes for typical cargo. We find that scatter plays a stronger role in cargo radiography than in typicalmedical imaging scenarios, even for low-density cargo, with scatter-toprimary ratios ranging from 0.14 for very low density cargo, to between 0.20 and 0.40 for typical cargo, and higher yet for dense cargo.

  1. Optimisation in general radiography

    PubMed Central

    Martin, CJ

    2007-01-01

    Radiography using film has been an established method for imaging the internal organs of the body for over 100 years. Surveys carried out during the 1980s identified a wide range in patient doses showing that there was scope for dosage reduction in many hospitals. This paper discusses factors that need to be considered in optimising the performance of radiographic equipment. The most important factor is choice of the screen/film combination, and the preparation of automatic exposure control devices to suit its characteristics. Tube potential determines the photon energies in the X-ray beam, with the selection involving a compromise between image contrast and the dose to the patient. Allied to this is the choice of anti-scatter grid, as a high grid ratio effectively removes the larger component of scatter when using higher tube potentials. However, a high grid ratio attenuates the X-ray beam more heavily. Decisions about grids and use of low attenuation components are particularly important for paediatric radiography, which uses lower energy X-ray beams. Another factor which can reduce patient dose is the use of copper filtration to remove more low-energy X-rays. Regular surveys of patient dose and comparisons with diagnostic reference levels that provide a guide representing good practice enable units for which doses are higher to be identified. Causes can then be investigated and changes implemented to address any shortfalls. Application of these methods has led to a gradual reduction in doses in many countries. PMID:21614270

  2. Image Acquisition and Quality in Digital Radiography.

    PubMed

    Alexander, Shannon

    2016-09-01

    Medical imaging has undergone dramatic changes and technological breakthroughs since the introduction of digital radiography. This article presents information on the development of digital radiography and types of digital radiography systems. Aspects of image quality and radiation exposure control are highlighted as well. In addition, the article includes related workplace changes and medicolegal considerations in the digital radiography environment. PMID:27601691

  3. Panoramic Measures for Oral Bone Mass in Detecting Osteoporosis

    PubMed Central

    Calciolari, E.; Donos, N.; Park, J.C.; Petrie, A.; Mardas, N.

    2015-01-01

    Different quantitative and qualitative indices calculated on oral panoramic radiographs have been proposed as useful tools to screen for reduced skeletal bone mineral density (BMD). Our aim was to systematically review the literature on linear and qualitative panoramic measures and to assess the accuracy of these indices by performing a meta-analysis of their sensitivity and specificity. The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement was followed. Fifty studies were included in the qualitative appraisal and 19 were considered for meta-analysis. The methodological quality of the retrieved studies, assessed with the QUADAS-2 tool, was on average low. Three indices were reported by most of the studies: mandibular cortical width, panoramic mandibular index, and the Klemetti index. Mandibular cortical width presented with a better accuracy in excluding osteopenia/osteoporosis (specificity), since patients with a cortical width more than 4 mm had a normal BMD in 90% of the cases. Almost all studies used a cutoff of 0.3 for the panoramic mandibular index, resulting in an estimated sensitivity and specificity in detecting reduced BMD, respectively, of 0.723 (SE 0.160; 95% confidence interval [CI], 0.352–0.926) and 0.733 (SE 0.066; 95% CI, 0.587–0.841). The presence of any kind of mandibular cortical erosion gave an estimated sensitivity and specificity in detecting reduced BMD, respectively, of 0.789 (SE 0.031; 95% CI, 0.721–0.843) and 0.562 (SE 0.047; 95% CI, 0.47–0.651) and a sensitivity and specificity in detecting osteoporosis, respectively, of 0.806 (SE 0.105; 95% CI, 0.528–0.9200) and 0.643 (SE 0.109; 95% CI, 0.417–0.820). The mandibular cortical width, panoramic mandibular index, and Klemetti index are overall useful tools that potentially could be used by dentists to screen for low BMD. Their limitations are mainly related to the experience/agreement between different operators and the different image quality

  4. Filters For Chest Radiography

    NASA Astrophysics Data System (ADS)

    Ramanathan, N.; Paron, J.

    1980-08-01

    The objective of low dose radiography is achieved by a judicious combination of proper kV selection, fast film-screen systems and beam filtration. A systematic study of filters was undertaken to evaluate the improvements that can be realized in terms of patient Entrance Skin Exposures (ESE) for chest radiographs. The Picker CD 135 Generator and the Automatic Chest Filmer with dynamic phototiming were used for the study. The kV dependence of ESE with various amounts of zinc and aluminum filtration is presented. The effect of filtration on image contrast is discussed. The variations of ESE with phantom thickness under different filtration conditions are also considered. It was found that the ESE can be reduced by as much as a factor of 1.8 ± .1 with no significant increase in tube loading.

  5. Multiple-image radiography

    NASA Astrophysics Data System (ADS)

    Wernick, Miles N.; Wirjadi, Oliver; Chapman, Dean; Zhong, Zhong; Galatsanos, Nikolas P.; Yang, Yongyi; Brankov, Jovan G.; Oltulu, Oral; Anastasio, Mark A.; Muehleman, Carol

    2003-12-01

    Conventional radiography produces a single image of an object by measuring the attenuation of an x-ray beam passing through it. When imaging weakly absorbing tissues, x-ray attenuation may be a suboptimal signature of disease-related information. In this paper we describe a new phase-sensitive imaging method, called multiple-image radiography (MIR), which is an improvement on a prior technique called diffraction-enhanced imaging (DEI). This paper elaborates on our initial presentation of the idea in Wernick et al (2002 Proc. Int. Symp. Biomed. Imaging pp 129-32). MIR simultaneously produces several images from a set of measurements made with a single x-ray beam. Specifically, MIR yields three images depicting separately the effects of refraction, ultra-small-angle scatter and attenuation by the object. All three images have good contrast, in part because they are virtually immune from degradation due to scatter at higher angles. MIR also yields a very comprehensive object description, consisting of the angular intensity spectrum of a transmitted x-ray beam at every image pixel, within a narrow angular range. Our experiments are based on data acquired using a synchrotron light source; however, in preparation for more practical implementations using conventional x-ray sources, we develop and evaluate algorithms designed for Poisson noise, which is characteristic of photon-limited imaging. The results suggest that MIR is capable of operating at low photon count levels, therefore the method shows promise for use with conventional x-ray sources. The results also show that, in addition to producing new types of object descriptions, MIR produces substantially more accurate images than its predecessor, DEI. MIR results are shown in the form of planar images of a phantom and a biological specimen. A preliminary demonstration of the use of MIR for computed tomography is also presented.

  6. Revealing of HII-regions in Galaxies with Panoramic Spectroscopy

    NASA Astrophysics Data System (ADS)

    Hakopian, S. A.; Balayan, S. K.

    2016-06-01

    Observations intended to investigation and revealing of nodes of processes of nuclear and starforming activity in galaxies were performed via panoramic spectroscopy. Data obtained on Mrk 1050 revealed evidence of starforming activity also outside the central engine of high surface brightness. Two small HII-regions, being likely a part of the chain, are located in the part of the spiral branch coming from the nucleus part.

  7. Panoramic view of the electrical Department & Boiler House Complex, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Panoramic view of the electrical Department & Boiler House Complex, looking southwest from the roof of the lower shops. Originally constructed in 1888, only sections of original walls remain. In the right foreground is the no. 2 steel foundry, originally constructed in 1888 and converted many times as different furnaces were added. Behind the buildings (to the south and west) is the Stony Creek River. - Johnson Steel Street Rail Company, Electrical Department & Boiler House, 525 Central Avenue, Johnstown, Cambria County, PA

  8. Panoramic Okavango Swamp, Botswana and Fires in Angola, Africa

    NASA Technical Reports Server (NTRS)

    1991-01-01

    In this panoramic view of the Okavango Swamp, Botswana, (19.0S, 22.0E), the Okavango River, seen in sunglint, flows into a topographic trough to form an inland delta. Water, trapped in the meandering delta distributaries is evaporated or transpired by vegetation. In Angola to the north, the many fires of the seasonal burning of savannah vegetation for land clearing, in preparation for agriculture, has filled the atmosphere with haze and smoke.

  9. Panoramic view from bluff south of Grand Coulee Dam; this ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Panoramic view from bluff south of Grand Coulee Dam; this segment of the panorama shows the western end of Crescent Bay Lake (in the foreground), the western limits of the town of Grand Coulee, part of Grand Coulee's transformer yard (center in the distance), and the concrete-lined feeder canal that extends to Banks Lake, looking northwest. - Columbia Basin Project, Grand Coulee, Grant County, WA

  10. Photocopy of panoramic photograph entitled "Ground Breaking, April 27, 1918, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Photocopy of panoramic photograph entitled "Ground Breaking, April 27, 1918, U.S.A. General Hospital no. 21…". Photograph by Rocky Mountain photo and is in the Fitzsimons Army Medical Center Public Affairs Office, building 120. Photograph in public domain as it is not copyrighted. - Fitzsimons General Hospital, Bounded by East Colfax to south, Peoria Street to west, Denver City/County & Adams County Line to north, & U.S. Route 255 to east, Aurora, Adams County, CO

  11. Dental radiology.

    PubMed

    Woodward, Tony M

    2009-02-01

    Dental radiology is the core diagnostic modality of veterinary dentistry. Dental radiographs assist in detecting hidden painful pathology, estimating the severity of dental conditions, assessing treatment options, providing intraoperative guidance, and also serve to monitor success of prior treatments. Unfortunately, most professional veterinary training programs provide little or no training in veterinary dentistry in general or dental radiology in particular. Although a technical learning curve does exist, the techniques required for producing diagnostic films are not difficult to master. Regular use of dental x-rays will increase the amount of pathology detected, leading to healthier patients and happier clients who notice a difference in how their pet feels. This article covers equipment and materials needed to produce diagnostic intraoral dental films. A simplified guide for positioning will be presented, including a positioning "cheat sheet" to be placed next to the dental x-ray machine in the operatory. Additionally, digital dental radiograph systems will be described and trends for their future discussed. PMID:19410234

  12. Dental Hygienist.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. Center on Education and Training for Employment.

    This document, which is designed for use in developing a tech prep competency profile for the occupation of dental hygienist, lists technical competencies and competency builders for 13 units pertinent to the health technologies cluster in general and 9 units specific to the occupation of dental hygienist. The following skill areas are covered in…

  13. Assessment of skeletal and dental ages of children and adolescents with type 1 diabetes mellitus.

    PubMed

    Bezerra, Ilana Sanamaika Queiroga; Topolski, Francielle; França, Suzana Nesi; Brücker, Márcia Rejane; Fernandes, Ângela

    2015-01-01

    The present study aimed to assess the skeletal and dental ages of type 1 diabetes mellitus (T1DM) patients. Therefore, panoramic and hand-wrist radiographs of 82 patients, aged between 5 and 15 years, were collected and divided into case and control groups. The case group consisted of 41 panoramic and 41 hand-wrist radiographs of T1DM patients, whereas the control group consisted of 41 panoramic and 41 hand-wrist radiographs of patients without T1DM. Skeletal age was assessed according to the method of Greulich and Pyle (1999), whereas dental age was assessed according to the method of Nolla (1960). Chi-square tests revealed no statistically significant differences between skeletal and dental ages between the case and control groups (p > 0.05). However, in the case group, the skeletal age of females was greater than that of age-matched males (p = 0.005). Considering that skeletal and dental growth of the case and control groups were closely related, clinical interventions involving orthodontics and dentomaxillofacial orthopedics should be equally performed both for healthy and specific patient groups, such as those with T1DM. PMID:25627889

  14. [The place of radiography in endodontic treatment carried out in general practice in Dakar].

    PubMed

    Gaye, F; Mbaye, M; Faye, B; Diallo, B

    2002-03-01

    An investigation conducted over dental surgeons of 52 dental offices in Dakar and it's near suburb (40 from private sector and 12 from public and quasi-public) has shown that the use of retro-alveolar radiography during endodontic treatment was not systematic, due to the price of retro-alveolar film, waste of time and relative facility of the endodontic treatment of monoradicular teeth. The preparatory negative is favored (32.70%) particularly by private dental surgeons, who use two retro-alveolar films for endodontic treatment: pre and post operative radiography (30%). The immediate post operator control is executed only in case of post-operator pains by public and quasi-public dental surgeons (16.67%) with one retro-alveolar film on average for the endodontic treatment; at term any radiographic control is done. Three retro-alveolar films per endodontic treatment were exceptionally used (9.61%) and offset incidences (15%) are not much used as well as support-films (angulators). The retro-alveolar radiography is still a reliable guide for a clinical success in endodontic treatment with a minimum of three retro-alveolar films and offset incidences. PMID:12061249

  15. Infraorbital ethmoid (Haller's) cells: a panoramic radiographic study

    PubMed Central

    Raina, A; Guledgud, M V; Patil, K

    2012-01-01

    Objective Haller's cells or infraorbital ethmoid cells refer to the ethmoidal pneumatization of the superior aspect of the maxillary sinus and floor of the orbit. The clinical importance of these entities initiated this study with an aim to determine the prevalence and characteristics of Haller's cells on panoramic radiographs. Methods The study group comprised 600 healthy adults of both genders with an age range of 18–60 years. One panoramic radiograph for each of the patients was made and interpreted for the presence of Haller's cells. The data collected were subjected to statistical analysis: frequencies/percentages, descriptive statistics, χ2 test and cross-tabulation (contingency table analysis) to obtain the results. Results Haller's cells were noted in 96 patients, accounting for a prevalence of 16%. Of these patients, 77.1% were unilateral while 22.9% were bilateral. Among 96 cases, a total of 204 cells were found. The majority of the cells were round or ovoid in shape. The unilocular type of Haller's cells occurring unilaterally was statistically significant. Conclusion This study has attempted to explore the characteristics of Haller's cells on panoramic radiographs. A description of Haller's cells on these radiographs may prove vital in enumerating the differential diagnosis for patients afflicted with intractable orofacial pain and reduce the risk of untoward intraoperative complications during endonasal procedures. PMID:22241882

  16. Prevelance of Haller’s Cells: A Panoramic Radiographic Study

    PubMed Central

    Gupta, Sarika; Patil, Neelkant; Kulkarni, Venkatesh V; Singh, Meenakshi; Laller, Sanjeev

    2014-01-01

    Background: Infraorbital ethmoid cells, also known as Haller’s cells can be seen on panoramic radiographs. These help in identification of various pathologies and patient symptoms. Objective: To determine the prevelance and characteristic of Haller’s cells on panoramic radiographs. Infraorbital ethmoid cells are extensions of ethmoid air cells into areas of orbit and maxillary sinus. Materials and Methods: This study comprised of 1000 panoramic radiographs of healthy adults of the age 18-80 years. Each radiograph was interpreted for the presence of haller’s cells. The data collected were then tabulated and subjected to descriptive statistics and chi-square test. Results: Haller’s cells were observed in 19.2% patients. Majority of cells were present unilaterally (176 cells) while only 15 were seen bilaterally. Maximum cells were oval in shape, unilocular and single in number. Conclusion: Presence of haller’s cells helps in enumerating the differential diagnosis for orofacial pain and in avoiding surgical complications in endonasal procedures. PMID:25386500

  17. Effects of Edentulism on Mandibular Morphology: Evaluation of Panoramic Radiographs

    PubMed Central

    Okşayan, Rıdvan; Asarkaya, Bayram; Palta, Nizamettin; Şimşek, İrfan; Sökücü, Oral; İşman, Eren

    2014-01-01

    Purpose. The objective of this study was to evaluate morphological changes of the mandible in edentulous and dentate subjects using panoramic radiographs. Materials and Methods. Panoramic radiographs were divided into the following three groups: Group I (completely edentulous group), Group II (old dentate group) and Group III (young dentate group). The research parameters of gonial angle, condylar height, ramus height, ramus notch depth, and antegonial notch depth were measured on panoramic radiographs. The Kruskal-Wallis statistical test was used to determine significant differences in mandibular morphological parameters among the three groups. The Mann-Whitney U test was used to compare the subgroups. Results. Significant differences were found only in ramus height between three groups. According to the Mann-Whitney U test, a significant difference was exhibited among Groups I and II in the ramus height parameter. No significant differences were found in the gonial angle, condylar height, ramus notch depth, or antegonial notch depth when comparing the young dentate, old dentate, and completely edentulous subjects. Conclusions. Significant differences were found only in ramus height between the groups. Ramus height may be an indicator that changed by years and tooth loss. It must be considered that ramus height can be decreased in edentulism. PMID:25202718

  18. Radiographic diagnosis of dental restoration misfit: a systematic review.

    PubMed

    Liedke, G S; Spin-Neto, R; da Silveira, H E D; Wenzel, A

    2014-12-01

    The objective of this study was to perform a systematic review on the use of radiographic methods for the diagnosis of misfit in dental prostheses and restorations. The MEDLINE bibliographic database was searched from 1950 to February 2014 for reports on the radiographic diagnosis of misfits. The search strategy was limited to English-language publications using the following combined MeSH terms in the search strategy: (Dental Restoration OR Dental Prosthesis OR Crown OR Inlays OR Dental Abutments) and (Dental Leakage OR Prosthesis Fitting OR Dental Marginal Adaptation OR Surface Properties) and (Radiography, Dental OR Radiography, Dental, Digital OR Cone-Beam Computed Tomography). Twenty-eight publications were identified and read in full text, and 14 studies fulfilled criteria for inclusion. Information regarding the use of radiographic methods for the diagnosis of misfits in dental prosthesis and restorations, and in which the methodology/results comprised information regarding how the sample was collected/prepared, the method, imaging protocol, presence of a reference test and the outcomes were evaluated. QUADAS criteria was used to rate the studies in high, moderate or low quality. The evidence supporting the use of radiographic methods for the diagnosis of misfits in dental prosthesis and restorations is limited to low-/moderate-quality studies. The well-established intra-oral orthogonal projection is still under investigation and considered the most appropriate method, both when evaluating the relation between dental restoration to tooth and abutment to implant. Studies using digital radiographs have not evaluated the effect of image post-processing, and tomography has not been evaluated. PMID:25142004

  19. Dental OCT

    NASA Astrophysics Data System (ADS)

    Wilder-Smith, Petra; Otis, Linda; Zhang, Jun; Chen, Zhongping

    This chapter describes the applications of OCT for imaging in vivo dental and oral tissue. The oral cavity is a diverse environment that includes oral mucosa, gingival tissues, teeth and their supporting structures. Because OCT can image both hard and soft tissues of the oral cavity at high resolution, it offers the unique capacity to identity dental disease before destructive changes have progressed. OCT images depict clinically important anatomical features such as the location of soft tissue attachments, morphological changes in gingival tissue, tooth decay, enamel thickness and decay, as well as the structural integrity of dental restorations. OCT imaging allows for earlier intervention than is possible with current diagnostic modalities.

  20. Upper Gastrointestinal (GI) Tract X-Ray (Radiography)

    MedlinePlus

    ... Resources Professions Site Index A-Z X-ray (Radiography) - Upper GI Tract Upper gastrointestinal tract radiography or ... X-ray? What is Upper Gastrointestinal (GI) Tract Radiography? Upper gastrointestinal tract radiography, also called an upper ...

  1. Assessment of quality and interpretation of panoramic radiographs obtained in the Lao People's Democratic Republic as part of a teleradiology collaboration with Japan.

    PubMed

    Matsumoto, Kunihito; Vongsa, Souksavanh; Nakajima, Ichiro; Ejima, Ken-Ichiro; Kohinata, Kiyomi; Suzuki, Toshihiro; Hosono, Shigeharu; Aboshi, Hirofumi; Kuwata, Fumiyuki; Otsuka, Kichibee

    2015-09-01

    As part of quality assessment of a teleradiology program we evaluated the validity of patient information received, the quality of panoramic radiography imaging in Laos, and the ability of a Laotian radiologist to detect temporomandibular joint abnormalities. The amount of patient information gathered from 2,021 scans of panoramic radiographs was evaluated by triage before image diagnosis. Among the radiographs from 2,021 patients, primary triage indicated that there was insufficient information for 794 (39.3%) patients. Secondary triage to assess imaging failure included 1,227 radiographs, four of which were excluded from imaging diagnosis because of unacceptable image flaws. In total, 2,446 joints from 1,223 radiographs were evaluated for temporomandibular joint abnormalities in order to compare the image interpretation abilities of Laotian and Japanese radiologists. The kappa coefficient was 0.836 (P < 0.01) for the agreement between the two observers in detecting temporomandibular joint abnormalities on radiographs. We conclude that additional efforts are needed in order to overcome the challenges of maintaining quality in imaging techniques and diagnoses in Laos. PMID:26369488

  2. Angular signal radiography.

    PubMed

    Li, Panyun; Zhang, Kai; Bao, Yuan; Ren, Yuqi; Ju, Zaiqiang; Wang, Yan; He, Qili; Zhu, Zhongzhu; Huang, Wanxia; Yuan, Qingxi; Zhu, Peiping

    2016-03-21

    Microscopy techniques using visible photons, x-rays, neutrons, and electrons have made remarkable impact in many scientific disciplines. The microscopic data can often be expressed as the convolution of the spatial distribution of certain properties of the specimens and the inherent response function of the imaging system. The x-ray grating interferometer (XGI), which is sensitive to the deviation angle of the incoming x-rays, has attracted significant attention in the past years due to its capability in achieving x-ray phase contrast imaging with low brilliance source. However, the comprehensive and analytical theoretical framework is yet to be presented. Herein, we propose a theoretical framework termed angular signal radiography (ASR) to describe the imaging process of the XGI system in a classical, comprehensive and analytical manner. We demonstrated, by means of theoretical deduction and synchrotron based experiments, that the spatial distribution of specimens' physical properties, including absorption, refraction and scattering, can be extracted by ASR in XGI. Implementation of ASR in XGI offers advantages such as simplified phase retrieval algorithm, reduced overall radiation dose, and improved image acquisition speed. These advantages, as well as the limitations of the proposed method, are systematically investigated in this paper. PMID:27136780

  3. The use of a radiopaque contrast medium in endodontic radiography.

    PubMed

    Shearer, A C; Wasti, F; Wilson, N H

    1996-03-01

    A series of in vitro studies were carried out to investigate the use and application of a radiopaque contrast medium in conventional periapical dental radiography for the diagnosis and evaluation of root canal systems. The water-soluble radiopaque contrast medium was introduced into the root canals of 30 first permanent maxillary and 30 first permanent mandibular molar teeth. The radiographic images of these teeth with and without radiopaque contrast medium in the root canal systems were compared and contrasted. Further comparisons were made with the same teeth rendered transparent. The results indicate that by standardizing the diagnostic criteria the inter-examiner reliability was in good agreement; it was independent of the radiographic technique used. The validity of the radiographs was enhanced by the use of the radiopaque contrast medium. The results confirm that, with the use of a radiopaque contrast medium, images of root canal systems are easier to read and interpret than plain radiographic images of root canal systems. The use of radiopaque contrast medium in endodontic radiography may be a valuable aid in the diagnosis and evaluation of root canal systems. This system would complement rather than replace plain radiography. PMID:9206431

  4. Dental Fluorosis

    MedlinePlus

    ... when children regularly consume fluoride during the teeth-forming years, age 8 and younger. Most dental fluorosis ... over a long period when the teeth are forming under the gums. Only children aged 8 years ...

  5. Dental Implants

    MedlinePlus Videos and Cool Tools

    ... facts so you can make an informed decision as to whether dental implants are right for your ... the jaw bone. It’s obviously not the same as the original connection , but functions just the same. ...

  6. Dental Caries (Tooth Decay)

    MedlinePlus

    ... Find Data by Topic > Dental Caries (Tooth Decay) Dental Caries (Tooth Decay) Main Content Dental caries (tooth decay) remains the most prevalent chronic ... important source of information on oral health and dental care in the United States since the early ...

  7. Dental MRI using wireless intraoral coils

    PubMed Central

    Ludwig, Ute; Eisenbeiss, Anne-Katrin; Scheifele, Christian; Nelson, Katja; Bock, Michael; Hennig, Jürgen; von Elverfeldt, Dominik; Herdt, Olga; Flügge, Tabea; Hövener, Jan-Bernd

    2016-01-01

    Currently, the gold standard for dental imaging is projection radiography or cone-beam computed tomography (CBCT). These methods are fast and cost-efficient, but exhibit poor soft tissue contrast and expose the patient to ionizing radiation (X-rays). The need for an alternative imaging modality e.g. for soft tissue management has stimulated a rising interest in dental magnetic resonance imaging (MRI) which provides superior soft tissue contrast. Compared to X-ray imaging, however, so far the spatial resolution of MRI is lower and the scan time is longer. In this contribution, we describe wireless, inductively-coupled intraoral coils whose local sensitivity enables high resolution MRI of dental soft tissue. In comparison to CBCT, a similar image quality with complementary contrast was obtained ex vivo. In-vivo, a voxel size of the order of 250∙250∙500 μm3 was achieved in 4 min only. Compared to dental MRI acquired with clinical equipment, the quality of the images was superior in the sensitive volume of the coils and is expected to improve the planning of interventions and monitoring thereafter. This method may enable a more accurate dental diagnosis and avoid unnecessary interventions, improving patient welfare and bringing MRI a step closer to becoming a radiation-free alternative for dental imaging. PMID:27021387

  8. CANDLE Syndrome: orodfacial manifestations and dental implications.

    PubMed

    Roberts, T; Stephen, L; Scott, C; di Pasquale, T; Naser-Eldin, A; Chetty, M; Shaik, S; Lewandowski, L; Beighton, P

    2015-01-01

    A South African girl with CANDLE Syndrome is reported with emphasis on the orodental features and dental management. Clinical manifestations included short stature, wasting of the soft tissue of the arms and legs, erythematous skin eruptions and a prominent abdomen due to hepatosplenomegaly. Generalized microdontia, confirmed by tooth measurement and osteopenia of her jaws, confirmed by digitalized radiography, were previously undescribed syndromic components. Intellectual impairment posed problems during dental intervention. The carious dental lesions and poor oral hygiene were treated conservatively under local anaesthetic. Prophylactic antibiotics were administered an hour before all procedures.Due to the nature of her general condition, invasive dental procedures were minimal. Regular follow-ups were scheduled at six monthly intervals. During this period, her overall oral health status had improved markedly.The CANDLE syndrome is a rare condition with grave complications including immunosuppression and diabetes mellitus. As with many genetic disorders, the dental manifestations are often overshadowed by other more conspicuous and complex syndromic features. Recognition of both the clinical and oral changes that occur in the CANDLE syndrome facilitates accurate diagnosis and appropriate dental management of this potentially lethal condition. PMID:26711936

  9. Dental MRI using wireless intraoral coils.

    PubMed

    Ludwig, Ute; Eisenbeiss, Anne-Katrin; Scheifele, Christian; Nelson, Katja; Bock, Michael; Hennig, Jürgen; von Elverfeldt, Dominik; Herdt, Olga; Flügge, Tabea; Hövener, Jan-Bernd

    2016-01-01

    Currently, the gold standard for dental imaging is projection radiography or cone-beam computed tomography (CBCT). These methods are fast and cost-efficient, but exhibit poor soft tissue contrast and expose the patient to ionizing radiation (X-rays). The need for an alternative imaging modality e.g. for soft tissue management has stimulated a rising interest in dental magnetic resonance imaging (MRI) which provides superior soft tissue contrast. Compared to X-ray imaging, however, so far the spatial resolution of MRI is lower and the scan time is longer. In this contribution, we describe wireless, inductively-coupled intraoral coils whose local sensitivity enables high resolution MRI of dental soft tissue. In comparison to CBCT, a similar image quality with complementary contrast was obtained ex vivo. In-vivo, a voxel size of the order of 250∙250∙500 μm(3) was achieved in 4 min only. Compared to dental MRI acquired with clinical equipment, the quality of the images was superior in the sensitive volume of the coils and is expected to improve the planning of interventions and monitoring thereafter. This method may enable a more accurate dental diagnosis and avoid unnecessary interventions, improving patient welfare and bringing MRI a step closer to becoming a radiation-free alternative for dental imaging. PMID:27021387

  10. Dental MRI using wireless intraoral coils

    NASA Astrophysics Data System (ADS)

    Ludwig, Ute; Eisenbeiss, Anne-Katrin; Scheifele, Christian; Nelson, Katja; Bock, Michael; Hennig, Jürgen; von Elverfeldt, Dominik; Herdt, Olga; Flügge, Tabea; Hövener, Jan-Bernd

    2016-03-01

    Currently, the gold standard for dental imaging is projection radiography or cone-beam computed tomography (CBCT). These methods are fast and cost-efficient, but exhibit poor soft tissue contrast and expose the patient to ionizing radiation (X-rays). The need for an alternative imaging modality e.g. for soft tissue management has stimulated a rising interest in dental magnetic resonance imaging (MRI) which provides superior soft tissue contrast. Compared to X-ray imaging, however, so far the spatial resolution of MRI is lower and the scan time is longer. In this contribution, we describe wireless, inductively-coupled intraoral coils whose local sensitivity enables high resolution MRI of dental soft tissue. In comparison to CBCT, a similar image quality with complementary contrast was obtained ex vivo. In-vivo, a voxel size of the order of 250•250•500 μm3 was achieved in 4 min only. Compared to dental MRI acquired with clinical equipment, the quality of the images was superior in the sensitive volume of the coils and is expected to improve the planning of interventions and monitoring thereafter. This method may enable a more accurate dental diagnosis and avoid unnecessary interventions, improving patient welfare and bringing MRI a step closer to becoming a radiation-free alternative for dental imaging.

  11. Measuring image quality in overlapping areas of panoramic composed images

    NASA Astrophysics Data System (ADS)

    Mitjà, Carles; Bover, Toni; Escofet, Jaume

    2012-06-01

    Several professional photographic applications uses the merging of consecutive overlapping images in order to obtain bigger files by means of stitching techniques or extended field of view (FOV) for panoramic images. All of those applications share the fact that the final composed image is obtained by overlapping the neighboring areas of consecutive individual images taken as a mosaic or a series of tiles over the scene, from the same point of view. Any individual image taken with a given lens can carry residual aberrations and several of them will affect more probably the borders of the image frame. Furthermore, the amount of distortion aberration present in the images of a given lens will be reversed in position for the two overlapping areas of a pair of consecutive takings. Finally, the different images used in composing the final one have corresponding overlapping areas taken with different perspective. From all the previously stated can be derived that the software employed must remap all the pixel information in order to resize and match image features in those overlapping areas, providing a final composed image with the desired perspective projection. The work presented analyse two panoramic format images taken with a pair of lenses and composed by means of a state of the art stitching software. Then, a series of images are taken to cover an FOV three times the original lens FOV, the images are merged by means of a software of common use in professional panoramic photography and the final image quality is evaluated through a series of targets positioned in strategic locations over the whole taking field of view. That allows measuring the resulting Resolution and Modulation Transfer Function (MTF). The results are shown compared with the previous measures on the original individual images.

  12. 9. THIRD IMAGE OF THE PANORAMIC SERIES WITH CONSIDERABLE OVERLAP. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. THIRD IMAGE OF THE PANORAMIC SERIES WITH CONSIDERABLE OVERLAP. A SETTLING TANK, SMOKESTACK FROM THE MILL'S BOILER ROOM, MILL ANNEX AND OTHER MILL OUT BUILDINGS ARE IN THE MIDDLE RIGHT OF THE IMAGE THE SUPERINTENDENTS HOUSE IS IN THE MIDDLE LEFT OF THE IMAGE SPANNING FROM LEFT TO RIGHT IN THE BACKGROUND IS THE TOWN OF BODIE. IN THE FAR BACKGROUND LEFT IS THE ROAD THAT IS THE ACCESS PARK. - Standard Gold Mill, East of Bodie Creek, Northeast of Bodie, Bodie, Mono County, CA

  13. Panoramic View of the Andes Mountains, Chile and Argentina

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This panoramic view of the Andes Mountains of Chile and Argentina (24.5S, 69.5W) is dominated by the yellows and browns of the coastal Atacama Desert and the full width of the Andes altiplano, about 300 miles. Winter snow can be seen capping the 22,000 to 23,000 ft. peaks of the Andes. Wisps of cirrus clouds lie over the altiplano and offshore fog obscures the coast. In the distance, the low Chaco Plain appears green with pastures and agriculture.

  14. Photocopy of left half of panoramic photograph marked "C 1928 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Photocopy of left half of panoramic photograph marked "C 1928 Goldbeck". Photograph appears to have been taken from 1919 water tower, no longer extant, looking southwest with a rotating camera to encompass the entire installation. Photograph in the Fitzsimons Army Medical Center Directorate of Public Works conference room, building 118. This photograph is in the public domain as it was never actually registered with the Copyright Office. - Fitzsimons General Hospital, Bounded by East Colfax to south, Peoria Street to west, Denver City/County & Adams County Line to north, & U.S. Route 255 to east, Aurora, Adams County, CO

  15. 7. THE BEGINNING OF A PANORAMIC SERIES VIEW LOOKING WEST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. THE BEGINNING OF A PANORAMIC SERIES VIEW LOOKING WEST NORTHWEST FROM THE UPHILL SIDE OF THE MILL. THE ORE RECEIVING HOUSE IS IN THE IMAGE CENTER, THE ORE DELIVERY TRESTLE EXTENDS FROM THE RECEIVING HOUSE TO THE MILL BUILDING IN THE BACKGROUND LEFT. IN THE MID-GROUND LEFT IS A CYLINDRICAL STRUCTURE BELIEVE TO BE A SETTLING TANK FROM A LATER CHEMICAL RETREATMENT OF THE TAILINGS IN THE FOREGROUND RIGHT IS AN EXTANT ORE BUCKET. - Standard Gold Mill, East of Bodie Creek, Northeast of Bodie, Bodie, Mono County, CA

  16. Second of three panoramic views of North Base as seen ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Second of three panoramic views of North Base as seen from top of Building 4500, Control Tower. View looks west (268°) at North Base complex. In foreground is taxiway, with Building 4456 (Fire House No. 4) at right. Building 4452 (Utility Vault) appears in extreme left foreground, with Building 4412 (Liquid Oxygen Repair Facility) and Building 4410 (Liquid Oxygen Storage) in extreme left background. In view over Building 4456 is the "loop" bound by Third, Fourth, A, and B Streets. Concrete slabs are all that remain of military housing constructed in the 1940s. - Edwards Air Force Base, North Base, North Base Road, Boron, Kern County, CA

  17. Fast and thermal neutron radiography

    NASA Astrophysics Data System (ADS)

    Cremer, Jay T.; Piestrup, Melvin A.; Wu, Xizeng

    2005-09-01

    There is a need for high brightness neutron sources that are portable, relatively inexpensive, and capable of neutron radiography in short imaging times. Fast and thermal neutron radiography is as an excellent method to penetrate high-density, high-Z objects, thick objects and image its interior contents, especially hydrogen-based materials. In this paper we model the expected imaging performance characteristics and limitations of fast and thermal radiography systems employing a Rose Model based transfer analysis. For fast neutron detection plastic fiber array scintllators or liquid scintillator filled capillary arrays are employed for fast neutron detection, and 6Li doped ZnS(Cu) phosphors are employed for thermal neutron detection. These simulations can provide guidance in the design, construction, and testing of neutron imaging systems. In particular we determined for a range of slab thickness, the range of thicknesses of embedded cracks (air-filled or filled with material such as water) which can be detected and imaged.

  18. Normal and pathological anatomy of the TMJ viewed by computerized panoramic arthroscopic images.

    PubMed

    Wang, Xudong; Yang, Chi; Goddard, Greg; Qiu, Weiliu

    2003-07-01

    The individual single images obtained to document TMJ arthroscopy are often difficult to interpret. The aim of this paper is to make available a new computer-aided image process system to reformat the panoramic arthroscopic images of the temporomandibular joint (TMJ). Arthroscopic images were input directly into a computer and memorized into a magneto optical disk. Using Photoshop 5.0 (Adobe Systems, Inc., Mountain View, CA) software for Windows 98 (Microsoft Corp., King County, WA) the images were edited and adjusted to compound sagittal and/or coronal panoramic images of normal articular surfaces as well as pathology of TMJ disorders. Normal TMJ sagittal and coronal two-dimensional composite panoramic arthroscopic images were achieved. The panoramic images of some intracapsular disorders (including disk displacement, osteoarthrosis, adhesion, and disk perforation) were also obtained. The computerized arthroscopic panoramic images are a new technique that may aid in the understanding of TMJ anatomy and TMJ disorders. PMID:12889676

  19. Quality assurance in orthodontic radiography.

    PubMed

    Brown, J E

    1995-02-01

    The implementation of a Quality Assurance (QA) programme in orthodontic radiography is designed to improve the quality of the resultant radiographs and to reduce the number of repeat exposures. This is particularly desirable in orthodontic practice where the majority of patients are young and therefore more at risk from the detrimental effects of X-rays. A programme is described and QA tests are given that may be applied in the surgery. Particular emphasis is placed on QA measures for extraoral radiography, since this is frequently undertaken in the treatment of the orthodontic patient. PMID:7786872

  20. Mosquitoes, flies and dental cavities: Dr. Howard Riley Raper's public campaign to prevent toothache.

    PubMed

    Christen, Arden G; Christen, Joan A

    2010-01-01

    Dr. Howard Riley Raper (1886-1978) was an early oral health pioneer and dental roentgenology faculty member of the Indiana Dental College (IDC) who single-handedly introduced key concepts in radiology to dentistry. Due to his efforts, IDC became in 1910-11 the first dental school to have a regular course in dental radiology. Virtually all American dental schools soon added this subject to their regular curriculum. Raper's text, Elementary and Dental Radiography (1913) became the first comprehensive student textbook of dental X-ray diagnosis. In his 1933 Blue Book entitled, The New Aim in the Care of the Teeth, Raper elaborated upon his mission to prevent caries, by comparing the insidious damages of tooth decay with the threat of insect-borne disease. PMID:20968230

  1. Panoramic, large-screen, 3-D flight display system design

    NASA Technical Reports Server (NTRS)

    Franklin, Henry; Larson, Brent; Johnson, Michael; Droessler, Justin; Reinhart, William F.

    1995-01-01

    The report documents and summarizes the results of the required evaluations specified in the SOW and the design specifications for the selected display system hardware. Also included are the proposed development plan and schedule as well as the estimated rough order of magnitude (ROM) cost to design, fabricate, and demonstrate a flyable prototype research flight display system. The thrust of the effort was development of a complete understanding of the user/system requirements for a panoramic, collimated, 3-D flyable avionic display system and the translation of the requirements into an acceptable system design for fabrication and demonstration of a prototype display in the early 1997 time frame. Eleven display system design concepts were presented to NASA LaRC during the program, one of which was down-selected to a preferred display system concept. A set of preliminary display requirements was formulated. The state of the art in image source technology, 3-D methods, collimation methods, and interaction methods for a panoramic, 3-D flight display system were reviewed in depth and evaluated. Display technology improvements and risk reductions associated with maturity of the technologies for the preferred display system design concept were identified.

  2. High-resolution panoramic images with megapixel MWIR FPA

    NASA Astrophysics Data System (ADS)

    Leboucher, Vincent; Aubry, Gilles

    2014-06-01

    In the continuity of its current strategy, HGH maintains a deep effort in developing its most recent product family: the infrared (IR) panoramic 360-degree surveillance sensors. During the last two years, HGH optimized its prototype Middle Wave IR (MWIR) panoramic sensor IR Revolution 360 HD that gave birth to Spynel-S product. Various test campaigns proved its excellent image quality. Cyclope, the software associated with Spynel, benefitted from recent image processing improvements and new functionalities such as target geolocalization, long range sensor slue to cue and facilitated forensics analysis. In the frame of the PANORAMIR project sustained by the DGA (Délégation Générale de l'Armement), HGH designed a new extra large resolution sensor including a MWIR megapixel Focal Plane Array (FPA) detector (1280×1024 pixels). This new sensor is called Spynel-X. It provides outstanding resolution 360-degree images (with more than 100 Mpixels). The mechanical frame of Spynel (-S and -X) was designed with the collaboration of an industrial design agency. Spynel got the "Observeur du Design 2013" label.

  3. Three-dimensional panoramic terrain reconstruction from aerial imagery

    NASA Astrophysics Data System (ADS)

    Yang, Ahua; Li, Xuejun; Xie, Jianwei; Wei, Yong

    2013-01-01

    A complete solution for effectively, automatically, and accurately reconstructing the three-dimensional (3-D) panoramic terrain from aerial imagery is presented. With enough premeasured and identified georeferences, we first estimate every camera's accurate intrinsic and extrinsic parameters by implementing bundle adjustment, which is introduced in detail. Afterward, the adjacent relationship of imagery is acquired from the cameras' position parameters. In addition, the formulas for corresponding area prediction and image rectification are derived according to the camera parameters. Subsequently, feature-based matching is conducted between adjacent image pairs to provide much more constraints for bundle adjustment. Area-based matching is applied to pairs of horizontal epipolar imagery for dense correspondence to produce dense spatial point cloud. Eventually, the mosaicked digital ortho map and digital elevation model of the whole imaging area are produced automatically by a series of steps including spatial intersection, Tin generation, differential correction, and color blending. Experimental results show that the root mean square (RMS) residual errors of check points in planimetry and altitude are, respectively, 0.039 and 0.170 m, demonstrating the high accuracy of camera orientation. The visualized panoramic 3-D realistic scene validates the feasibility and effectiveness of the proposed solution.

  4. Observing implantable collamer lens dislocation by panoramic ultrasound biomicroscopy

    PubMed Central

    Shi, M; Kong, J; Li, X; Yan, Q; Zhang, J

    2015-01-01

    Purpose Observe the image characteristics and dislocation of implantable collamer lenses (ICL) following their use to correct high myopia. Methods A total of 127 patients (242 eyes); 64 females (50.3%) and 63 males (49.7%) were included in this retrospective study with ICL V4 implantation and mean spherical equivalent −9.08±2.04 diopters (D). Panoramic ultrasound biomicroscopy (UBM) was utilized to observe anterior segment morphology and ICL location at various follow-up periods (1 week preoperative, followed by 1, 3, 6, and yearly postoperative). Results Twenty-eight ICL eyes (11.2%) were noted to have abnormal postoperative positioning. The central vault of 12 eyes was too high with ICL decentration, mean central vault 1.14±0.39 mm; 10 eyes were too low but without ICL decentration, mean central vault 0.13±0.11 mm. The remaining subjects were only ICL decentration without abnormal central vault, mean central vault was 0.54±0.28 mm. Conclusions This study shows the abnormal characteristics regarding ICL locations. The ICL dislocation closely correlates with the central vault. The ICL dislocation is the primary cause of several postoperative complications. Panoramic UBM is one of the most effective imaging means to observe the ICL positioning and its stability after implantable surgery. PMID:25613840

  5. Using Vertical Panoramic Images to Record a Historic Cemetery

    NASA Astrophysics Data System (ADS)

    Tommaselli, A. M. G.; Polidori, L.; Hasegawa, J. K.; Camargo, P. O.; Hirao, H.; Moraes, M. V. A.; Rissate, E. A., Jr.; Henrique, G. R.; Abreu, P. A. G.; Berveglieri, A.; Marcato, J., Jr.

    2013-07-01

    In 1919, during colonization of the West Region of São Paulo State, Brazil, the Ogassawara family built a cemetery and a school with donations received from the newspaper Osaka Mainichi Shimbum, in Osaka, Japan. The cemetery was closed by President Getúlio Vargas in 1942, during the Second World War. The architecture of the Japanese cemetery is a unique feature in Latin America. Even considering its historical and cultural relevance, there is a lack of geometric documentation about the location and features of the tombs and other buildings within the cemetery. As an alternative to provide detailed and fast georeferenced information about the area, it is proposed to use near vertical panoramic images taken with a digital camera with fisheye lens as the primary data followed by bundle adjustment and photogrammetric restitution. The aim of this paper is to present a feasibility study on the proposed technique with the assessment of the results with a strip of five panoramic images, taken over some graves in the Japanese cemetery. The results showed that a plant in a scale of 1 : 200 can be produced with photogrammetric restitution at a very low cost, when compared to topographic surveying or laser scanning. The paper will address the main advantages of this technique as well as its drawbacks, with quantitative analysis of the results achieved in this experiment.

  6. A PANORAMIC VIEW OF THE MILKY WAY ANALOG NGC 891

    SciTech Connect

    Mouhcine, M.; Ibata, R.; Rejkuba, M.

    2010-05-01

    Recent panoramic observations of the dominant spiral galaxies of the Local Group have revolutionized our view of how these galaxies assemble their mass. However, it remains completely unclear whether the properties of the outer regions of the Local Group large spirals are typical. Here, we present the first panoramic view of a spiral galaxy beyond the Local Group, based on the largest, contiguous, ground-based imaging survey to date resolving the stellar halo of the nearest prime analog of the Milky Way, NGC 891 (D {approx} 10 Mpc). The low surface brightness outskirts of this galaxy are populated by multiple, coherent, and vast substructures over the {approx}90 kpc x 90 kpc extent of the survey. These include a giant stream, the first to be resolved into stars beyond the Local Group using ground-based facilities, that loops around the parent galaxy up to distances of {approx}50 kpc. The bulge and the disk of the galaxy are found to be surrounded by a previously undetected large, flat, and thick cocoon-like stellar structure at vertical and radial distances of up to {approx}15 kpc and {approx}40 kpc, respectively.

  7. Enhanced surveillance system based on panomorph panoramic lenses

    NASA Astrophysics Data System (ADS)

    Thibault, Simon

    2007-04-01

    Modern surveillance and security systems demand a technological approach because only technology can provide highly efficient vigilance, a certainty of detection and a fast response 100% of the time. Recent developments, including new wide-angle lenses, advanced cameras, IP networks and video analysis technology, provide significant improvements in system performance and flexibility. This paper presents a new advanced surveillance system featuring a panoramic Panomorph lens for event detection, recognition and identification over a 360-degree area with 100% coverage. This innovative approach provides enhanced performance with better pixel/cost ratio. Intelligent video technology enables the video camera to be "more" than just a video camera; it allows the panoramic image to follow events (such as moving objects or unauthorized behavior) in real time, which in turn allows the operator to focus his/her activity on a narrow field pan/tilt camera without losing any information in the field. Adding incremental capabilities such as a Panomorph lens-based imager to an existing surveillance video system can provide improvements in operational efficiency and effectiveness. Foreseen applications are in the fields of border surveillance, high-security environments, aerospace and defense, mass transit, public security and wherever the need for total awareness is a prerequisite.

  8. Dental Calculus Arrest of Dental Caries

    PubMed Central

    Keyes, Paul H.; Rams, Thomas E.

    2016-01-01

    Background An inverse relationship between dental calculus mineralization and dental caries demineralization on teeth has been noted in some studies. Dental calculus may even form superficial layers over existing dental caries and arrest their progression, but this phenomenon has been only rarely documented and infrequently considered in the field of Cariology. To further assess the occurrence of dental calculus arrest of dental caries, this study evaluated a large number of extracted human teeth for the presence and location of dental caries, dental calculus, and dental plaque biofilms. Materials and methods A total of 1,200 teeth were preserved in 10% buffered formal saline, and viewed while moist by a single experienced examiner using a research stereomicroscope at 15-25× magnification. Representative teeth were sectioned and photographed, and their dental plaque biofilms subjected to gram-stain examination with light microscopy at 100× magnification. Results Dental calculus was observed on 1,140 (95%) of the extracted human teeth, and no dental carious lesions were found underlying dental calculus-covered surfaces on 1,139 of these teeth. However, dental calculus arrest of dental caries was found on one (0.54%) of 187 evaluated teeth that presented with unrestored proximal enamel caries. On the distal surface of a maxillary premolar tooth, dental calculus mineralization filled the outer surface cavitation of an incipient dental caries lesion. The dental calculus-covered carious lesion extended only slightly into enamel, and exhibited a brown pigmentation characteristic of inactive or arrested dental caries. In contrast, the tooth's mesial surface, without a superficial layer of dental calculus, had a large carious lesion going through enamel and deep into dentin. Conclusions These observations further document the potential protective effects of dental calculus mineralization against dental caries.

  9. Age estimation by modified Demirjian's method (2004) and its applicability in Tibetan young adults: A digital panoramic study

    PubMed Central

    Bijjaragi, Shobha C; Sangle, Varsha A; Saraswathi, FK; Patil, Veerendra S; Ashwini Rani, SR; Bapure, Sunil K

    2015-01-01

    Context: Estimation of the age is a procedure adopted by anthropologists, archeologists and forensic scientists. Different methods have been undertaken. However none of them meet the standards as Demirjian's method since 1973. Various researchers have applied this method, in both original and modified form (Chaillet and Demirjian in 2004) in different ethnic groups and the results obtained were not satisfactory. Aims: To determine the applicability and accuracy of modified Demirjian's method of dental age estimation (AE) in 8–18 year old Tibetan young adults to evaluate the interrelationship between dental and chronological age and the reliability between intra- and inter observer relationship. Settings and Design: Clinical setting and computerized design. Subjects and Methods: A total of 300 Tibetan young adults with an age range from 8 to 18 years were recruited in the study. Digital panoramic radiographs (DPRs) were evaluated as per the modified Demirjian's method (2004). Statistical Analysis Used: Pearson correlation, paired t-test, linear regression analysis. Results: Inter -and intraobserver reliability revealed a strong agreement. A positive and strong association was found between chronological age and estimated dental age (r = 0.839) with P < 0.01. Modified Demirjian method (2004) overestimated the age by 0.04 years (2.04 months)in Tibetan young adults. Conclusions: Results suggest that, the modified Demirjian method of AE is not suitable for Tibetan young adults. Further studies: With larger sample size and comparision with different methods of AE in a given population would be an interesting area for future research. PMID:26097317

  10. The significance of cone beam computed tomography for the visualization of anatomical variations and lesions in the maxillary sinus for patients hoping to have dental implant-supported maxillary restorations in a private dental office in Japan

    PubMed Central

    2014-01-01

    Objectives The purpose of the present study was to elucidate the significance of cone bean computed tomography (CBCT) for patients hoping to undergo implant-supported restorations of the maxilla. Therefore, two studies were planned. One was to compare the prevalence of anatomic variations and lesions in the maxillary sinus on CBCT of patients hoping to undergo implant-supported restorations of the maxilla with that in patients with other chief complaints in a private dental office in Japan. The other study was to elucidate the limitations of panoramic radiographs in the detection of anatomic variations and lesions in the maxillary sinus. Study design Sixty-one pairs of panoramic radiographs and CBCT were retrospectively analyzed in two groups of patients, those who hoped to undergo implant-supported restorations in the maxilla (Implant group) and those who did not (Non-implant group). The presence of anatomic variations and lesions in the maxillary sinus were analyzed. Results The detection rate of mucosal thickening was significantly higher in the Implant group than in the Non-implant group. The detection rates for the features analyzed were significantly lower on panoramic radiographs. In particular, the detection rates of internal and anterior locations of some features were noticeably lower on panoramic radiographs. A significant relationship was found between the change in the detection rate on panoramic radiographs and the widths of mucosal thickening or the lengths of the major axis of SOLs in the maxillary sinus. If the width of mucosal thickening or the length of the major axis of SOLs was <3 mm or <4 mm, respectively, the detection rate on panoramic radiographs was significantly decreased. Conclusion CBCT is important for patients hoping to undergo implant-supported restorations of the maxilla because of the mucosal thickening in the maxillary sinus in such patients and their lower detection rates on panoramic radiographs. PMID:24884983

  11. Secular trend of dental development in Dutch children.

    PubMed

    Vucic, Strahinja; de Vries, Esther; Eilers, Paul H C; Willemsen, Sten P; Kuijpers, Mette A R; Prahl-Andersen, Birte; Jaddoe, Vincent W V; Hofman, Albert; Wolvius, Eppo B; Ongkosuwito, Edwin M

    2014-09-01

    Many studies have established dental age standards for different populations; however, very few studies have investigated whether dental development is stable over time on a population level. Therefore, the aim of this study was to analyze changes in dental maturity in Dutch children born between 1961 and 2004. We used 2,655 dental panoramic radiographs of 2- to 16-year-old Dutch children from studies performed in three major cities in the Netherlands. Based on a trend in children born between 1961 and 1994, we predicted that a child of a certain age and gender born in 1963 achieved the same dental maturity on average, 1.5 years later than a child of the same age born 40 years later. After adjusting for the birth year of a child in the analysis, the regression coefficient of the city variable was reduced by 56.6% and it remained statistically significant. The observed trend from 1961 to 1994 was extrapolated to 9- to 10-year-old children born in 2002-2004, and validation with the other samples of children with the same characteristics showed that 95.9%-96.8% of the children had dental maturity within the 95% of the predicted range. Dental maturity score was significantly and positively associated with the year of birth, gender, and age in Dutch children, indicating a trend in earlier dental development during the observation period, 1961-2004. These findings highlight the necessity of taking the year of birth into account when assessing dental development within a population with a wider time span. PMID:24912457

  12. Dental Caries

    PubMed Central

    Burgess, Ralph C.

    1988-01-01

    Dental caries is one of the most prevalent diseases afflicting mankind. It reached a peak in the 1950s but has been declining drastically in recent years in children and young adults. This article describes the three contributing factors in dental caries: microbial plaque, tooth susceptibility, and diet, and discusses practical preventive measures which help to reduce caries incidence. Some of these, such as vaccines and antimicrobial varnishes, are still in the research stages, while others, such as sucrose substitutes, low-calorie sweeteners, and limitation of frequency of sugar snacks are well established and can be promoted by family physicians. PMID:21253193

  13. Evaluation of calcified carotid atheroma on panoramic radiographs and Doppler ultrasonography in an older population

    PubMed Central

    Atalay, Yusuf; Asutay, Fatih; Agacayak, Kamil Serkan; Koparal, Mahmut; Adali, Fahri; Gulsun, Belgin

    2015-01-01

    Aim The aim of this study is to determine the reliability of panoramic radiograph (PR) as a screening tool for the detection of calcified carotid atheroma (CCA) by comparing it with Doppler ultrasonography (DU) examination. A second aim was to evaluate the relationship among CCA, systemic diseases, smoking, and body mass index in an older population. Materials and methods A total of 1,650 PRs of patients aged over 45 years (736 males and 914 females) were randomly selected. All the patients had been referred to the Faculty of Dentistry, Afyon Kocatepe University, Afyonkarahisar, Turkey, during 2013–2014 for routine PR screening. Medical data were collected from the archival records of the dental school. The patients were divided into two groups: Group A (study group), CCA findings were confirmed by DU (n=59); and Group B (control group), CCA findings were not confirmed by DU (n=34). Results Of the 1,650 individuals, 93 (5.63%) were detected to have CCA on PR. The population consisted of 43 males and 50 females with mean age of 59.84±10.92 years. No difference was determined in respect of CCA between the sexes (P=0.745). There was a significant difference between Group A and Group B in respect of hypertension (P=0.004). But there was no difference between Group A and Group B in respect of age (P=0.495), BMI (P=0.756), diabetes (P=0.168), and smoking (P=0.482) distribution. Conclusion Although PR cannot be used as an initial diagnostic method when searching for CCA, dentists should be aware of CCA on a routine PR, particularly in older patients who may also have the risk factors of obesity, diabetes mellitus, hypertension, and smoking. Recognizing of CCA especially in hypertensive patients could potentially increase the length and quality of life for individuals. PMID:26185431

  14. Pneumatized Articular Eminence and Assessment of Its Prevalence and Features on Panoramic Radiographs

    PubMed Central

    Khojastepour, Leila; Ezoddini, Fatemeh; Zeighami, Noshafarin

    2015-01-01

    Objectives: Pneumatized articular eminence or tubercle (PAT) is an air cell cavity in the zygomatic process of the temporal bone. Pneumatization of articular eminence may be seen incidentally on panoramic radiographs (PRs) as a unilocular or multilocular radiolucent defect. The aim of this study was to assess the prevalence and the pattern of PAT on PR in an Iranian population. Materials and Methods: A total of 3,098 PRs belonging to 1,735 females and 1,363 males were retrospectively investigated for the presence and radiographic features of PAT. All PRs were taken for routine dental examination. Chi-square test, univariate odds ratio (OR) and corresponding 95% confidence interval (95% CI) and binary logistic regression were used for statistical analysis. Results: Overall, PAT was found in 2.1 % of cases including 41 females and 23 males (with a mean age of 33.23±12.43 and 35.64±13.24 years, respectively, range 19–69 years). There were 40 unilateral and 24 bilateral cases (total: 88 PATs) including 49 unilocular and 39 multilocular cases. There was no significant difference in PAT between males and females or different age groups (P>0.05 and all CIs included 1.00). Binary logistic regression indicated that there was no relationship between the presence of PAT and age or sex. Conclusion: Knowledge about this anatomical variation is helpful for clinicians who are planning to perform temporomandibular joint surgery. They should assess the radiographic imaging thoroughly before the surgery. It can also provide valuable information to understand the differential diagnosis of pathological entities in this region. PMID:26622277

  15. a Method of Generating Panoramic Street Strip Image Map with Mobile Mapping System

    NASA Astrophysics Data System (ADS)

    Tianen, Chen; Yamamoto, Kohei; Tachibana, Kikuo

    2016-06-01

    This paper explores a method of generating panoramic street strip image map which is called as "Pano-Street" here and contains both sides, ground surface and overhead part of a street with a sequence of 360° panoramic images captured with Point Grey's Ladybug3 mounted on the top of Mitsubishi MMS-X 220 at 2m intervals along the streets in urban environment. On-board GPS/IMU, speedometer and post sequence image analysis technology such as bundle adjustment provided much more accuracy level position and attitude data for these panoramic images, and laser data. The principle for generating panoramic street strip image map is similar to that of the traditional aero ortho-images. A special 3D DEM(3D-Mesh called here) was firstly generated with laser data, the depth map generated from dense image matching with the sequence of 360° panoramic images, or the existing GIS spatial data along the MMS trajectory, then all 360° panoramic images were projected and stitched on the 3D-Mesh with the position and attitude data. This makes it possible to make large scale panoramic street strip image maps for most types of cities, and provides another kind of street view way to view the 360° scene along the street by avoiding the switch of image bubbles like Google Street View and Bing Maps Streetside.

  16. Comparison of the diagnostic performance of panoramic and occlusal radiographs in detecting submandibular sialoliths

    PubMed Central

    Kim, Jun Ho; Aoki, Eduardo Massaharu; Abdala-Júnior, Reinaldo; Asaumi, Junichi; Arita, Emiko Saito

    2016-01-01

    Purpose The aim of this study was to assess and compare the diagnostic performance of panoramic and occlusal radiographs in detecting submandibular sialoliths. Materials and Methods A total of 40 patients (20 cases and 20 controls) were included in this retrospective study. Cases were defined as subjects with a submandibular sialolith confirmed by computed tomography (CT), whereas controls did not have any submandibular calcifications. Three observers with different expertise levels assessed panoramic and occlusal radiographs of all subjects for the presence of sialoliths. Intraobserver and interobserver agreement were assessed using the kappa test. Sensitivity, specificity, accuracy, positive and negative predictive values, and the diagnostic odds ratio of panoramic and occlusal radiographs in screening for submandibular sialoliths were calculated for each observer. Results The sensitivity and specificity values for occlusal and panoramic radiographs all ranged from 80% to 100%. The lowest values of sensitivity and specificity observed among the observers were 82.6% and 80%, respectively (P=0.001). Intraobserver and interobserver agreement were higher for occlusal radiographs than for panoramic radiographs, although panoramic radiographs demonstrated a higher overall accuracy. Conclusion Both panoramic and occlusal radiographic techniques displayed satisfactory diagnostic performance and should be considered before using a CT scan to detect submandibular sialoliths. PMID:27358815

  17. Panoramic camera on the Yutu lunar rover of the Chang'e-3 mission

    NASA Astrophysics Data System (ADS)

    Yang, Jian-Feng; Li, Chun-Lai; Xue, Bin; Ruan, Ping; Gao, Wei; Qiao, Wei-Dong; Lu, Di; Ma, Xiao-Long; Li, Fu; He, Ying-Hong; Li, Ting; Ren, Xin; Yan, Xing-Tao

    2015-11-01

    The Chang'e-3 panoramic camera, which is composed of two cameras with identical functions, performances and interfaces, is installed on the lunar rover mast. It can acquire 3D images of the lunar surface based on the principle of binocular stereo vision. By rotating and pitching the mast, it can take several photographs of the patrol area. After stitching these images, panoramic images of the scenes will be obtained. Thus the topography and geomorphology of the patrol area and the impact crater, as well as the geological structure of the lunar surface, will be analyzed and studied. In addition, it can take color photographs of the lander using the Bayer color coding principle. It can observe the working status of the lander by switching between static image mode and dynamic video mode with automatic exposure time. The focal length of the lens on the panoramic camera is 50 mm and the field of view is 19.7° × 14.5°. Under the best illumination and viewing conditions, the largest signal-to-noise ratio of the panoramic camera is 44 dB. Its static modulation transfer function is 0.33. A large number of ground testing experiments and on-orbit imaging results show that the functional interface of the panoramic camera works normally. The image quality of the panoramic camera is satisfactory. All the performance parameters of the panoramic camera satisfy the design requirements.

  18. Sensor modeling, self-calibration and accuracy testing of panoramic cameras and laser scanners

    NASA Astrophysics Data System (ADS)

    Amiri Parian, Jafar; Gruen, Armin

    2010-01-01

    Terrestrial Linear Array CCD-based panoramic cameras have been used for purely imaging purposes, but they also have a high potential for use in high accuracy measurement applications. The imaging geometry and the high information content of those images make them suitable candidates for quantitative image analysis. For that a particular sensor model has to be established and the inherent accuracy potential has to be investigated. We developed a sensor model for terrestrial Linear Array-based panoramic cameras by means of a modified bundle adjustment with additional parameters, which models substantial deviations of a real camera from the ideal one. We used 3D straight-line information in addition to tie points to conduct a full calibration and orientation without control point information. Due to the similarity of the operation of laser scanners to panoramic cameras the sensor model of the panoramic cameras was extended for the self-calibration of laser scanners. We present the joint sensor model for panoramic cameras and laser scanners and the results of self-calibration, which indicate a subpixel accuracy level for such highly dynamic systems. Finally we demonstrate the systems' accuracy of two typical panoramic cameras in 3D point positioning, using both a minimal number of control points and a free network adjustment. With these new panoramic imaging devices we have additional powerful sensors for image recording and efficient 3D object modeling.

  19. Dental Assistant.

    ERIC Educational Resources Information Center

    Michigan State Univ., East Lansing. Coll. of Agriculture and Natural Resources Education Inst.

    This curriculum guide, developed for use in dental assistant education programs in Michigan, describes a task-based curriculum that can help a teacher to develop a classroom management system where students learn by doing. It is based on task analysis and reflects the skills, knowledge, and attitudes that employers expect entry-level dental…

  20. Dental crowns

    MedlinePlus

    ... cover a tooth Replace a misshapen tooth or dental implant Correct a misaligned tooth Talk to your dentist ... the tooth pulled and replaced with a tooth implant. Your crown could chip or crack: If you grind your teeth or clench your jaw, you may need to ...

  1. Dental Training Films.

    ERIC Educational Resources Information Center

    Veterans Administration Medical Center, Washington, DC.

    This dental training films catalog is organized into two sections. Section I is a category listing of the films by number and title, indexed according to generalized headings; categories are as follow: anatomy, articulator systems, complete dentures, dental assisting, dental laboratory technology, dental materials, dental office emergencies,…

  2. Genetic algorithm for bundle adjustment in aerial panoramic stitching

    NASA Astrophysics Data System (ADS)

    Zhang, Chunxiao; Wen, Gaojin; Wu, Chunnan; Wang, Hongmin; Shang, Zhiming; Zhang, Qian

    2015-03-01

    This paper presents a genetic algorithm for bundle adjustment in aerial panoramic stitching. Compared with the conventional LM (Levenberg-Marquardt) algorithm for bundle adjustment, the proposed bundle adjustment combining the genetic algorithm optimization eliminates the possibility of sticking into the local minimum, and not requires the initial estimation of desired parameters, naturally avoiding the associated steps, that includes the normalization of matches, the computation of homography transformation, the calculations of rotation transformation and the focal length. Since the proposed bundle adjustment is composed of the directional vectors of matches, taking the advantages of genetic algorithm (GA), the Jacobian matrix and the normalization of residual error are not involved in the searching process. The experiment verifies that the proposed bundle adjustment based on the genetic algorithm can yield the global solution even in the unstable aerial imaging condition.

  3. Automatic panoramic image stitching and free exploration in virtual scenery

    NASA Astrophysics Data System (ADS)

    Wang, Qiang; Li, Cailin; Ji, Peihuan; Hu, Hualiang

    2009-10-01

    This paper presented an automatic panorama generation and free roaming algorithm for the tedious previous approaches on panorama generation and limitations of single-viewpoint roaming. Firstly, it describes the single-viewpoint panorama generation method: detecting the image point features in SIFT operator, getting the robust homography estimation in RANSAC and stitching the panoramic images by multi-band blending. Secondly, we present the free roaming method. In this method the corresponding pixels in new-viewpoint image can be set from the original images matching points and the new-viewpoint image can be blended by corresponding TIN piece rendering at last. Experimental results show that it is practicable and meets the actual requirements.

  4. Panoramic monocentric imaging using fiber-coupled focal planes.

    PubMed

    Stamenov, Igor; Arianpour, Ashkan; Olivas, Stephen J; Agurok, Ilya P; Johnson, Adam R; Stack, Ronald A; Morrison, Rick L; Ford, Joseph E

    2014-12-29

    Monocentric lenses provide high-resolution wide field of view imaging onto a hemispherical image surface, which can be coupled to conventional focal planes using fiber-bundle image transfer. We show the design and characterization of a 2-glass concentric F/1.0 lens, and describe integration of 5 Mpixel 1.75µm pitch back-side illuminated color CMOS sensors with 2.5µm pitch fiber bundles, then show the fiber-coupled lens compares favorably in both resolution and light collection to a 10x larger conventional F/4 wide angle photographic lens. We describe assembly of the monocentric lens and 6 adjacent sensors with focus optomechanics into an extremely compact 30Mpixel panoramic imager with a 126° "letterbox" format field of view. PMID:25607140

  5. An innovative algorithm for panoramic representation in observation systems

    NASA Astrophysics Data System (ADS)

    Luison, Cristian; Aquilanti, Valeria; Riccobono, Aldo; Liberace, Claudio

    2013-06-01

    This document presents the study and test carried out for the development of an innovative algorithm designed to create a panoramic representation of the scene scanned by observation systems operating with passive sensors. The purpose of the algorithm is to represent 360° of scene using staring sensors mounted on stabilized or semi-stabilized platforms, without requirements on video output, both in terms of the transmission format and in terms of frame rate. The algorithm is real-time and does not require step-and-stare technique or special systems to scan the scene. The architecture of the algorithm requires a very low computational cost for the electronics contained in a Multi-Functional Display (MDP) used in defense applications. The algorithm has been implemented and tested on the JANUS NAVAL system, where the results were very satisfactory. Today, a patent is pendent.

  6. The shell game: a panoramic view of Fornax

    NASA Astrophysics Data System (ADS)

    Bate, N. F.; McMonigal, B.; Lewis, G. F.; Irwin, M. J.; Gonzalez-Solares, E.; Shanks, T.; Metcalfe, N.

    2015-10-01

    We present a panoramic study of the Fornax dwarf spheroidal galaxy, using data obtained as part of the VLT Survey Telescope (VST) ATLAS Survey. The data presented here - a subset of the full survey - uniformly cover a region of 25 deg2 centred on the galaxy, in g, r and i bands. This large area coverage reveals two key differences to previous studies of Fornax. First, data extending beyond the nominal tidal radius of the dwarf highlight the presence of a second distinct red giant branch population. This bluer red giant branch appears to be co-eval with the horizontal branch population. Secondly, a shell structure located approximately 1.4° from the centre of Fornax is shown to be a mis-identified background overdensity of galaxies. This last result casts further doubt on the hypothesis that Fornax underwent a gas-rich merger in its relatively recent past.

  7. Assessment of the Horizontal and Vertical Position of Mental Foramen in Indian Population in Terms of Age and Sex in Dentate Subjects by Pano-ramic Radiographs: A Retrospective Study with Review of Literature

    PubMed Central

    Parnami, Priyanka; Gupta, Deepak; Arora, Vishal; Bhalla, Saurabh; Kumar, Adarsh; Malik, Rashi

    2015-01-01

    Objective : To familiarize new criteria to access vertical position of mental foramen in panoramic radiographs. Furthermore, to determine and compare the position and symmetry of mental foramen in horizontal as well as in vertical plane in Indian population and to compare the results with those reported for other populations in the literature. Further gender differences in mental foramen position were also accessed to comment on the reliability of panoramic radiographs for sex determination. Methods and Material : Six hundred digital panoramic radiographs were selected and studied regarding the location and symmetry of mental foramen. They were also compared with the other studies in the literature. The method employed is similar to that described by Al Jasser and Nwoku for horizontal position and Fishal et al. for vertical position of mental foramen. Certain modifications were carried out in Fishal’s criteria for vertical position assessment. Results : The commonest position of the mental foramen in horizontal plane was in line with the longitudinal axis of the second premolar (61.0%) while in vertical plane it was found to be located inferior to the apex of second premolar (72.2%). Conclusion : Mental foramen exists in different locations and possesses many variations. Hence, Individual, gender, age, race and assessing technique largely influence these variations. It suggests that the clinicians should carefully identify these anatomical landmarks, by analyzing all influencing factors, prior to their diagnostic or the other dental, surgical and implant operation. PMID:26464599

  8. Dose distribution and mapping with 3D imaging presentation in intraoral and panoramic examinations

    NASA Astrophysics Data System (ADS)

    Chen, Hsiu-Ling; Huang, Yung-Hui; Wu, Tung-Hsin; Wang, Shih-Yuan; Lee, Jason J. S.

    2011-10-01

    In current medical imaging applications, high quality images not only provide more diagnostic value for anatomic delineation but also offer functional information for treatment direction. However, this approach would potentially subscribe higher radiation dose in dental radiographies, which has been putatively associated with low-birth-weight during pregnancy, which affects the hypothalamus-pituitary-thyroid axis or thereby directly affects the reproductive organs. The aim of this study was to apply the high resolution 3-D image mapping technique to evaluate radiation doses from the following aspects: (1) verifying operating parameters of dental X-ray units, (2) measuring the leakage radiations and (3) mapping dose with 3-D radiographic imaging to evaluate dose distribution in head and neck regions. From the study results, we found that (1) leakage radiation from X-ray units was about 21.31±15.24 mR/h (<100 mR/h), (2) error of actual tube voltage for 60 kVp setting was from 0.2% to 6.5%, with an average of 2.5% (<7%) and (3) the error of exposure time for a 0.5-1.5 s setting was within 0.7-8.5%, with an average of 7.3% (<10%) error as well. Our 3-D dose mapping demonstrated that dose values were relatively lower in soft tissues and higher in bone surfaces compared with other investigations. Multiple causes could contribute to these variations, including irradiation geometry, image equipment and type of technique applied, etc. From the results, we also observed that larger accumulated doses were presented in certain critical organs, such as salivary gland, thyroid gland and bone marrow. Potential biological affects associated with these findings warrant further investigation.

  9. First Panoramic View From The Surface Of Mars

    NASA Technical Reports Server (NTRS)

    1976-01-01

    First panoramic view by Viking 1 from the surface of Mars. The out of focus spacecraft component toward left center is the housing for the Viking sample arm, which is not yet deployed. Parallel lines in the sky are an artifact and are not real features. However, the change of brightness from horizon towards zenith and towards the right (west) is accurately reflected in this picture, taken in late Martian afternoon. At the horizon to the left is a plateau-like prominence much brighter than the foreground material between the rocks. The horizon features are approximately three kilometers (1.8 miles) away. At left is a collection of fine-grained material reminiscent of sand dunes. The dark sinuous markings in left foreground are of unknown origin. Some unidentified shapes can be perceived on the hilly eminence at the horizon towards the right. A horizontal cloud stratum can be made out halfway from the horizon to the top of the picture. At left is seen the low gain antenna for receipt of commands from the Earth. The projections on or near the horizon may represent the rims distant impact craters. In right foreground are color charts for Lander camera calibration, a mirror for the Viking magnetic properties experiment and part of a grid on the top of the Lander body. At upper right is the high gain dish antenna for direct communication between landed spacecraft and Earth. Toward the right edge is an array of smooth fine-grained material which shows some hint of ripple structure and may be the beginning of a large dune field off to the right of the picture, which joins with dunes seen at the top left in this 300o panoramic view. Some of the rocks appear to be undercut on one side and partially buried by drifting sand on the other.

  10. Dental education and dental practice.

    PubMed Central

    Moore, J R

    1984-01-01

    This paper relates recent modes of dental practice to changes that the public and government are likely to ask the health care professions to make in the future. As usual they are asking for the best of all worlds. First, that we maintain the clinical model to the highest standards of personal dental care based and tested against the best research at our disposal, whilst we ensure there is no reduction in the high technical standards for which british dentists have a reputation. Second, that the profession is required to consider ways of providing care on the medicosocial model for the whole community at an economic level the country will afford. The broad changes in dental education have been reviewed, from the technical apprenticeship to the establishment of strong university departments in teaching hospitals. The importance of a sound biomedical foundation and of research both to education and the credibility of dental practice as a primary health care profession is stressed if the profession is to retain its position as a sister to medicine and not slide down to that of a technical ancillary. PMID:6374141

  11. Digital radiographic equipment in the Belgian dental office.

    PubMed

    Gijbels, F; Debaveye, D; Vanderstappen, M; Jacobs, R

    2005-01-01

    A survey was performed among Belgian dentists to evaluate the use and management of digital radiographic equipment. The majority of respondents work as general dental practitioners. One out of eight sets of equipment for extraoral exposures is digital. For intraoral radiography, 30% of the equipment is digital. While exposure time is reduced by about 50% for digital intraoral radiography compared with conventional radiography, no differences can be found between different conventional film speed classes. Appropriate collimation of the radiation beam is only sparingly used. Beam aiming devices to hold the film and position the radiation beam are not used by the majority of dentists. While 25% of the respondents stand behind a protective wall during exposure, 8% of dentists remain next to the patient during exposure while assisting in holding the film inside the mouth. A minority of the latter practitioners wear lead aprons. PMID:16461489

  12. An automatic and effective tooth isolation method for dental radiographs

    NASA Astrophysics Data System (ADS)

    Lin, P.-L.; Huang, P.-W.; Cho, Y. S.; Kuo, C.-H.

    2013-03-01

    Tooth isolation is a very important step for both computer-aided dental diagnosis and automatic dental identification systems, because it will directly affect the accuracy of feature extraction and, thereby, the final results of both types of systems. This paper presents an effective and fully automatic tooth isolation method for dental X-ray images, which contains up-per-lower jaw separation, single tooth isolation, over-segmentation verification, and under-segmentation detection. The upper-lower jaw separation mechanism is based on a gray-scale integral projection to avoid possible information loss and incorporates with the angle adjustment to handle skewed images. In a single tooth isolation, an adaptive windowing scheme for locating gap valleys is proposed to improve the accuracy. In over-segmentation, an isolation-curve verification scheme is proposed to remove excessive curves; and in under-segmentation, a missing-teeth detection scheme is proposed. The experimental results demonstrate that our method achieves the accuracy rates of 95.63% and 98.71% for the upper and lower jaw images, respectively, from the test database of 60 bitewing dental radiographs, and performs better for images with severe teeth occlusion, excessive dental works, and uneven illumination than that of Nomir and Abdel-Mottaleb's method. The method without upper-lower jaw separation step also works well for panoramic and periapical images.

  13. ASSOCIATION BETWEEN DENTAL AND SKELETAL MATURATION STAGES IN CROATIAN SUBJECTS.

    PubMed

    Srkoc, Tamara; Mestrović, Senka; Anić-Milosević, Sandra; Slaj, Mladen

    2015-12-01

    This study investigated the relationships between the stages of calcification of teeth and cervical vertebral maturation. The sample consisted of 295 subjects (129 male and 166 female), mean age 13.36 ± 2.65 (range 7-18) years. Dental age was evaluated from panoramic radiographs according to the method of Demirjian. Cervical vertebral maturation was determined on lateral cephalometric radiographs using cervical vertebrae maturation stages (CVS). For assessing the relationship between cervical vertebral and dental maturation, percentage distributions of the stages of calcification for each studied tooth were calculated. Only in the first CVS stage, boys and girls were of the same age. In all other stages (CVS 2-CVS 6) girls were by 0.98 (range 0.23-1.86) younger than boys. Gender differences in the mineralization pattern were also observed. It was found that dental maturation was finished earlier in female subjects. The highest correlation coefficient between dental and skeletal maturity was found for second premolars. Mineralization pattern of second premolars could be considered as a guideline for prediction of the pubertal growth spurt. Dental maturation stages might be clinically useful as a reliable indicator of facial growth. PMID:27017718

  14. System for uncollimated digital radiography

    DOEpatents

    Wang, Han; Hall, James M.; McCarrick, James F.; Tang, Vincent

    2015-08-11

    The inversion algorithm based on the maximum entropy method (MEM) removes unwanted effects in high energy imaging resulting from an uncollimated source interacting with a finitely thick scintillator. The algorithm takes as input the image from the thick scintillator (TS) and the radiography setup geometry. The algorithm then outputs a restored image which appears as if taken with an infinitesimally thin scintillator (ITS). Inversion is accomplished by numerically generating a probabilistic model relating the ITS image to the TS image and then inverting this model on the TS image through MEM. This reconstruction technique can reduce the exposure time or the required source intensity without undesirable object blurring on the image by allowing the use of both thicker scintillators with higher efficiencies and closer source-to-detector distances to maximize incident radiation flux. The technique is applicable in radiographic applications including fast neutron, high-energy gamma and x-ray radiography using thick scintillators.

  15. Oral and dental imaging equipment and techniques for small animals.

    PubMed

    Coffman, Curt R; Brigden, Glenn M

    2013-05-01

    In the diagnosis and treatment of oral and dental diseases in dogs and cats, digital intraoral radiography offers many advantages over the use of standard dental radiographic film, including rapid image generation, easier exposure correction, enhancement, and paperless storage. Digital image receptors can be divided into 2 main types, direct digital systems using charged coupled devices and complementary metal oxide semiconductor sensors, and indirect digital systems using phosphor plates with a computerized scanner. Each system is paired with a computer software system to allow handling, visualization, enhancement, sharing, and archiving of the images. PMID:23643018

  16. Acquired Wharton's duct stenosis after dental radiographs treated with sialendoscopy.

    PubMed

    Kieliszak, Christopher R; Shokri, Tom; Joshi, Arjun S

    2015-01-01

    Salivary gland trauma may result in ductal stenosis and chronic sialadenitis. We describe a case of an 81-year-old woman with a history of intermittent left submandibular swelling that began after recent dental examination and radiographs. Diagnostic sialendoscopy was performed and demonstrated a near complete distal stenosis. It was determined that trauma experienced during dental radiography may have resulted in the patient's ductal obstruction and subsequent sialadenitis. This case illustrates an unusual presentation of non-sialolith-related ductal obstruction in the submandibular gland, treated with sialendoscopic-assisted sialodochoplasty. PMID:25917069

  17. Mobile accelerator neutron radiography system

    NASA Astrophysics Data System (ADS)

    Dance, W. E.; Carollo, S. F.; Bumgardner, H. M.

    1984-10-01

    The use of neutron radiography for the inspection and maintenance of large structures such as aircraft has been delayed by the absence of a mobile system particularly suited to the requirements of field use. This report describes the production, extensive field testing, evaluation and disposition of the first mobile neutron radiography system to satisfy the majority of requirements for field use. The system is based upon the concept of a mobile on-off neutron radiography system based on a sealed-tube ion accelerator as neutron source demonstrated earlier by the Vought Corporation. Primary features of the system are its self-propelled mobility, versatile positioning capability scaled to Army helicopter dimensions, an on-off beam capability, exposure capability measured in minutes, and suitability for AMMRC laboratory and field use. Included in the report are a description of all components of the system, an evaluation of the operation of the system, an evaluation of its radiographic capabilities, a description of installation elements for the AMMRC site, and recommendations for next-generation systems.

  18. Design of aspherical surfaces for panoramic imagers using multi-populations genetic algorithm

    NASA Astrophysics Data System (ADS)

    Wang, Li-Ping; Liang, Zhong-zhu; Jin, Chun-Shui

    2009-05-01

    A design method of aspherical surface for panoramic imaging system with two mirrors using multi-populations genetic algorithms is proposed. Astigmatism induced by mirrors may significantly compromise image resolution. To solve this problem, we induced algebraic expression of astigmatism in panoramic imager based on generalized Coddington equation and theory of geometric optics. Then, we propose an optimization process for mirror profile design to eliminate astigmatism and provide purposely-designed projection formula with aid of MPGA. A series of polynomial expressions of aspherical surfaces are obtained and procedures of the design are presented. In order to facilitate ray tracing and aberration calculation, even asphere surface model is obtained by using of hybrid schemes combining MPGA and damped least squares. Finally, a prototype of the catadioptric panoramic imager has been developed and panoramic ring image is obtained.

  19. Photographic technology development project: Timber typing in the Tahoe Basin using high altitude panoramic photography

    NASA Technical Reports Server (NTRS)

    Ward, J. F.

    1981-01-01

    Procedures were developed and tested for using KA-80A optical bar camera panoramic photography for timber typing forest land and classifying nonforest land. The study area was the south half of the Lake Tahoe Basin Management Unit. Final products from this study include four timber type map overlays on 1:24,000 orthophoto maps. The following conclusions can be drawn from this study: (1) established conventional timber typing procedures can be used on panoramic photography if the necessary equipment is available, (2) The classification and consistency results warrant further study in using panoramic photography for timber typing; and (3) timber type mapping can be done as fast or faster with panoramic photography than with resource photography while maintaining comparable accuracy.

  20. Direction and movement angular velocity determining of cloudiness with panoramic images of the sky

    NASA Astrophysics Data System (ADS)

    Galileiskii, Viktor P.; Elizarov, Alexey I.; Kokarev, Dmitrii V.; Morozov, Aleksandr M.

    2014-11-01

    This article gives a short overview to method of direction determining and visible angular velocity of movement determining of cloudiness based on set of panoramic images of cloudy sky, obtained by "Fisheye" wide-angle lens.

  1. 6. INTERIOR OVERVIEW WITH TURBINE WATERWHEEL GOVERNOR. PANORAMIC VIEW 1/2, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. INTERIOR OVERVIEW WITH TURBINE WATERWHEEL GOVERNOR. PANORAMIC VIEW 1/2, LOOKING SOUTHEAST. - Santa Ana River Hydroelectric System, SAR-3 Powerhouse, San Bernardino National Forest, Redlands, San Bernardino County, CA

  2. Dental x-rays

    MedlinePlus

    ... or impacted teeth The presence and extent of dental caries (cavities) Bone damage (such as from periodontitis ) Abscessed ... Dental x-rays can reveal dental cavities (tooth decay) before they ... take yearly bitewings for the early development of cavities.

  3. [Absorbed doses in dental radiology].

    PubMed

    Bianchi, S D; Roccuzzo, M; Albrito, F; Ragona, R; Anglesio, S

    1996-01-01

    The growing use of dento-maxillo-facial radiographic examinations has been accompanied by the publication of a large number of studies on dosimetry. A thorough review of the literature is presented in this article. Most studies were carried out on tissue equivalent skull phantoms, while only a few were in vivo. The aim of the present study was to evaluate in vivo absorbed doses during Orthopantomography (OPT). Full Mouth Periapical Examination (FMPE) and Intraoral Tube Panoramic Radiography (ITPR). Measurements were made on 30 patients, reproducing clinical conditions, in 46 anatomical sites, with 24 intra- and 22 extra-oral thermoluminiscent dosimeters (TLDS). The highest doses were measured, in orthopantomography, at the right mandibular angle (1899 mu Gy) in FMPE on the right naso-labial fold (5640 mu Gy and in ITPR on the palatal surface of the left second upper molar (1936 mu Gy). Intraoral doses ranged from 21 mu Gy, in orthopantomography, to 4494 mu Gy in FMPE. Standard errors ranged from 142% in ITPR to 5% in orthopantomography. The highest rate of standard errors was found in FMPE and ITPR. The data collected in this trial are in agreement with others in major literature reports. Disagreements are probably due to different exam acquisition and data collections. Such differences, presented comparison in several sites, justify lower doses in FMPE and ITPR. Advantages and disadvantages of in vivo dosimetry of the maxillary region are discussed, the former being a close resemblance to clinical conditions of examination and the latter the impossibility of collecting values in depth of tissues. Finally, both ITPR and FMPE required lower doses than expected, and can be therefore reconsidered relative to their radiation risk. PMID:8966249

  4. Methods for monitoring patient dose in dental radiology.

    PubMed

    Helmrot, Ebba; Thilander-Klang, Anne

    2010-01-01

    Different types of X-ray equipment are used in dental radiology, such as intra-oral, panoramic, cephalometric, cone-beam computed tomography (CBCT) and multi-slice computed tomography (MSCT) units. Digital receptors have replaced film and screen-film systems and other technical developments have been made. The radiation doses arising from different types of examination are sparsely documented and often expressed in different radiation quantities. In order to allow the comparison of radiation doses using conventional techniques, i.e. intra-oral, panoramic and cephalometric units, with those obtained using, CBCT or MSCT techniques, the same quantities and units of dose must be used. Dose determination should be straightforward and reproducible, and data should be stored for each image and clinical examination. It is shown here that air kerma-area product (P(KA)) values can be used to monitor the radiation doses used in all types of dental examinations including CBCT and MSCT. However, for the CBCT and MSCT techniques, the methods for the estimation of dose must be more thoroughly investigated. The values recorded can be used to determine the diagnostic standard doses and to set diagnostic reference levels for each type of clinical examination and equipment used. It should also be possible to use these values for the estimation and documentation of organ or effective doses. PMID:20223852

  5. Dental Holography

    NASA Astrophysics Data System (ADS)

    Dirtoft, Ingegerd

    1983-12-01

    Ten years have passed since the first articles appeared in this new field. The qualities of the laser light together with the need of contactless 3-D measurements for different dental purposes seemed to be extremely promising, but still just a few scientists have used the method and mostly for laboratory studies. For some reason there has been a preponderance for orthodontic measurements. This seems to be a bit peculiar from holographic view compared with measurements for engineering purposes, which usually are made on metals. So naturally holography can become a clinical tool for measurements in the field of fixed bridges, removable partial dentures and implants. One of the problems is that the need for holography in dental research must be fulfilled in collaboration with physicists. Only a two-way communication during an entire experiment can balance both technical and odontological demands and thus give practical and clinical important results. The need for an easy way of handling the evaluation to get all required information is another problem and of course the holographic equipment must be converted to a box easy to handle for everyone. At last the position of dental holography today is going to be carefully examined together with an attempt to look into the hopefully exciting and not to utopic future for this research field.

  6. Real-time target tracking for a 360-degree panoramic IR imager

    NASA Astrophysics Data System (ADS)

    Olson, C. C.; Waterman, J. R.; Nichols, J. M.

    2014-06-01

    We introduce a detection and tracking algorithm for panoramic imaging systems intended for operations in high-clutter environments. The algorithm combines correlation- and model-based tracking in a manner that is robust to occluding objects but without the need for a separate collision prediction module. Large data rates associated with the panoramic imager necessitate the use of parallel computation on graphics processing units. We discuss the queuing and tracking algorithms as well as practical considerations required for real-time implementation.

  7. Prevalence and imaging characteristics of detectable tonsilloliths on 482 pairs of consecutive CT and panoramic radiographs

    PubMed Central

    2013-01-01

    Background Recent studies suggest that tonsilloliths are clinically related to halitosis and tonsillar abscess. Based on our empirical knowledge, tonsilloliths are relatively commonly encountered in daily clinical practice. It has been reported that the detection rate of tonsilloliths was under 24% in previous reports, although experience suggests otherwise. The purpose of the study was to evaluate the prevalence and characteristics of tonsilloliths using computed tomography (CT). In addition, the possible causes of low detection rates on panoramic radiographs were evaluated based on comparisons between CT images and panoramic radiographs in order to elucidate the limitations of visualizing the area around the palatine tonsils on panoramic radiographs. Methods 482 pairs of CT images and panoramic radiographs were retrospectively assessed with respect to the presence and characteristics of tonsilloliths. In addition, the causes in cases of disagreement between the two modalities were analyzed. Results The detection rate of tonsilloliths was 46.1% using CT scans, unlike previous reports. The characteristics of tonsillolith were dot-like figures with about 300-500 Hounsfield units within the palatine tonsil under the soft palate. The most common length of tonsilloliths was about 3 or 4 mm. As the subjects aged, the detection rate increased gradually. A significant difference in the tonsillolith detection rate was found between the over and under 40-year-old groups (p < 0.0001). However, the detection rate of tonsilloliths was only 7.3% on panoramic radiographs. A significant correlation was observed between the detection rate of tonsilloliths on panoramic radiographs and CT number (Spearman r = 0.429), size, (Spearman r = 0.318), and number of tonsilloliths (Spearman r = 0.333). Conclusion The present results suggest that tonsilloliths are relatively more common than previously suggested. However, panoramic radiographs detect only a small percentage

  8. Plasma-flash radiography utilizing a molybdenum target in dentistry

    SciTech Connect

    Yamamoto, Mariko; Takabe, Akihito; Sakamaki, Kimio

    1995-12-31

    The construction and the radiographic characteristics of a plasma flash x-ray generator having a molybdenum-target (anode tip) triode are described. This generator was primarily designed in order to perform soft radiography in dental medicine and employed the following essential components: a high-voltage power supply, a low-impedance coaxial transmission line with a gap switch, a coaxial oil condenser of 0.2 {micro}F, a turbo-molecular pump, a Krytron pulser as a trigger device, and a flash x-ray tube. The high-voltage main condenser of 0.2 {micro}F was charged from 40 to 60 kV by the power supply, and the electric charges in the condenser were discharged to the tube after closing the gap switch. Because this tube employed a long target, the plasma x-ray source which consists of molybdenum ions and electrons was easily produced by the target evaporating. The maximum tube voltage was nearly equivalent to the initial charging voltage of the main condenser, and the maximum current had a value of about 25 kA with a charging voltage of 60 kV. The average width of flash x rays was less than 1 {micro}s, and the time-integrated x-ray intensity with a charging voltage of 60 kV was approximately 20 {micro}C/kg at 1.0 m per pulse. The characteristic K-series intensity substantially increased according to increases in the charging voltage. High-speed dental radiography was performed by using a laser timing switch and a trigger-delay device.

  9. Plasma-flash radiography utilizing a molybdenum target in dentistry

    NASA Astrophysics Data System (ADS)

    Yamamoto, Mariko; Takabe, Akihito; Sakamaki, Kimio; Sato, Eiichi; Takahashi, Kei; Sagae, Michiaki; Oizumi, Teiji; Hayasi, Yasuomi; Sasaki, Katsuaki; Tamakawa, Yoshiharu; Yanagisawa, Toru

    1995-09-01

    The construction and the radiographic characteristics of a plasma flash x-ray generator having a molybdenum-target (anode tip) triode are described. This generator was primarily designed in order to perform soft radiography in dental medicine and employed the following essential components: a high-voltage power supply, a low-impedance coaxial transmission line with a gap switch, a coaxial oil condenser of 0.2 (mu) F, a turbo-molecular pump, a Krytron pulser as a trigger device, and a flash x-ray tube. The high-voltage main condenser of 0.2 (mu) F was charged from 40 to 60 kV by the power supply, and the electric charges in the condenser were discharged to the tube after closing the gap switch. Because this tube employed a long target, the plasma x-ray source which consists of molybdenum ions and electrons was easily produced by the target evaporating. The maximum tube voltage was nearly equivalent to the initial charge voltage of the main condenser, and the maximum current had a value of about 25 kA with a charging voltage of 60 kV. The average width of flash x rays was less than 1 microsecond(s) , and the time-integrated x-ray intensity with a charging voltage of 60 kV was approximately 20 (mu) C/kg at 1.0 m per pulse. The characteristic K-series intensity substantially increased according to increases in the charged voltage. High-speed dental radiography was performed using a laser timing switch and a trigger-delay device.

  10. Dose measurements in intraoral radiography using thermoluminescent dosimeters

    NASA Astrophysics Data System (ADS)

    Azorín, C.; Azorín, J.; Aguirre, F.; Rivera, T.

    2015-01-01

    The use of X-ray in medicine demands to expose the patient and the professional to the lowest radiation doses available in agreement with ALARA philosophy. The reference level for intraoral dental radiography is 7 mGy and, in Mexico, a number of examinations of this type are performed annually. It is considered that approximately 25% of all the X-rays examinations carried out in our country correspond to intraoral radiographies. In other hand, most of the intraoral X-ray equipment correspond to conventional radiological systems using film, which are developed as much manual as automatically. In this work the results of determining the doses received by the patients in intraoral radiological examinations made with different radiological systems using LiF:Mg,Cu,P+PTFE thermoluminescent dosimeters are presented. In some conventional radiological systems using film, when films are developed manual or automatically, incident kerma up to 10.61 ± 0.74 mGv were determined. These values exceed that reference level suggested by the IAEA and in the Mexican standards for intraoral examinations.

  11. Dental Fear among Medical and Dental Undergraduates

    PubMed Central

    Hakim, H.; Razak, I. A.

    2014-01-01

    Objective. To assess the prevalence and level of dental fear among health related undergraduates and to identify factors causing such fear using Kleinknecht's Dental Fear Survey (DFS) questionnaire. Methods. Kleinknecht's DFS questionnaire was used to assess dental fear and anxiety among the entire enrollment of the medical and dental undergraduates' of the University of Malaya. Results. Overall response rate was 82.2%. Dental students reported higher prevalence of dental fear (96.0% versus 90.4%). However, most of the fear encountered among dental students was in the low fear category as compared to their medical counterpart (69.2 versus 51.2%). Significantly more medical students cancelled dental appointment due to fear compared to dental students (P = 0.004). “Heart beats faster” and “muscle being tensed” were the top two physiological responses experienced by the respondents. “Drill” and “anesthetic needle” were the most fear provoking objects among respondents of both faculties. Conclusion. Dental fear and anxiety are a common problem encountered among medical and dental undergraduates who represent future health care professionals. Also, high level of dental fear and anxiety leads to the avoidance of the dental services. PMID:25386615

  12. Use of Digital Technology and Support Software Programs in the Private Dental Offices in Nevada

    ERIC Educational Resources Information Center

    Fattore-Bruno, LaDeane

    2009-01-01

    The purpose of this survey research was to determine the diffusion of digital radiography, the electronic oral health record (EOHR), digital intraoral photography, and diagnosis and clinical decision-making support software into the dental offices of Nevada. A cross-sectional survey design was utilized with a random sample of 600 Nevada dentists.…

  13. Retromolar Canal Associated with Age, Side, Sex, Bifid Mandibular Canal, and Accessory Mental Foramen in Panoramic Radiographs of Brazilians

    PubMed Central

    Capote, Ticiana Sidorenko de O.; Gonçalves, Marcela de Almeida; Campos, Juliana Álvares Duarte Bonini

    2015-01-01

    Background. The retromolar canal (RMC) is an anatomical variation that can cause complications in dental procedures. Method. The RMC was evaluated according to age, sex, and presence of accessory mandibular canal and accessory mental foramen, on both sides in 500 panoramic radiographs, belonging to individuals at the age of 7 to 20 years. The associations of interest were studied through Fisher's Exact Test and Pearson's Chi-Square Test, and the correlation was studied through Pearson's Correlation Coefficient (r). The significance level used was 5%. Results. The RMC was observed in 44 radiographs (8.8%), and out of those 24 were females. There was no statistically significant association between the RMC and age (p > 0.05; Fisher's Exact Test), sex (p = 0.787; Pearson's Chi-Square Test), amount of mandibular canals and mental foramina, on both sides (p > 0.05; Pearson's Chi-Square Test). There was a significant association between RMC and side, the higher frequency of the canal being on the right side (p < 0.05; Fisher's Exact Test). Conclusions. Despite the low occurrence of the RMC, its identification and the verification of its dimensions and path are relevant, mainly in cases when anesthetic and surgical procedures can present failures or difficulties. PMID:26366300

  14. Research and implementation of the algorithm for unwrapped and distortion correction basing on CORDIC for panoramic image

    NASA Astrophysics Data System (ADS)

    Zhang, Zhenhai; Li, Kejie; Wu, Xiaobing; Zhang, Shujiang

    2008-03-01

    The unwrapped and correcting algorithm based on Coordinate Rotation Digital Computer (CORDIC) and bilinear interpolation algorithm was presented in this paper, with the purpose of processing dynamic panoramic annular image. An original annular panoramic image captured by panoramic annular lens (PAL) can be unwrapped and corrected to conventional rectangular image without distortion, which is much more coincident with people's vision. The algorithm for panoramic image processing is modeled by VHDL and implemented in FPGA. The experimental results show that the proposed panoramic image algorithm for unwrapped and distortion correction has the lower computation complexity and the architecture for dynamic panoramic image processing has lower hardware cost and power consumption. And the proposed algorithm is valid.

  15. Panoramic imaging mass-spectrometer for planetary studies

    NASA Astrophysics Data System (ADS)

    Vaisberg, O.; Berthelier, J.; Torkar, K.; Leblanc, F.; Escoubet, P.; Woch, J.; Baumjohann, W.; Avanov, L.; Burch, J.; McComas, D.; Delcourt, D.; Wurz, P.; Grishin, V.; Smirnov, V.; Babkin, V.; Szego, K.

    2004-12-01

    Plasma diagnostics can provide extremely useful information for solar system studies. Neutral and ion sputtering from the surface leads to the formation of neutral and ion exospheres with compositions that reflect the surface composition modified by ionization and transport processes around the body. Measurements of ion composition and velocity distributions provide important information about surface composition and its recycling. Plasma measurements from low altitude spacecraft and landers on planetary bodies without atmospheres can be used to map the surface composition, while spectrometers onboard spacecraft orbiting planets with atmosphere are used for study of planetary losses, mass-exchange with the solar wind, and the long-term evolution of their environment. To perform reliable measurements of planetary plasmas a complete 3-dimensional velocity distributions of various ion species is necessary. In addition, if fast measurements of the major ion species are the main goal of plasma physics studies, precise measurements of the minor ion composition are often essential to unveil important properties of the atmosphere or the surface. Therefore ion mass spectrometers for solar system missions require both the capability of making fast measurements of the 3D-velocity distribution of ions and high mass resolution for detailed composition studies. We describe a novel type of miniature panoramic ion mass-spectrometer suitable for making such 3-dimensional measurements of ion components with high mass resolution. The feeding electron optics of our plasma analyzer (CAMERA) allows for fast measurements within an instantaneous 2p field of view, which has no gaps and can be accomplished on either stabilized or rotating spacecraft, or landers. It is followed by a time-of-flight mass-spectrometer that retains imaging capabilities of the feeding optics and provides mass-resolution M/ΔM in excess of 100. Our spectrometer also provides flexible control of the energy

  16. Using Google Streetview Panoramic Imagery for Geoscience Education

    NASA Astrophysics Data System (ADS)

    De Paor, D. G.; Dordevic, M. M.

    2014-12-01

    Google Streetview is a feature of Google Maps and Google Earth that allows viewers to switch from map or satellite view to 360° panoramic imagery recorded close to the ground. Most panoramas are recorded by Google engineers using special cameras mounted on the roofs of cars. Bicycles, snowmobiles, and boats have also been used and sometimes the camera has been mounted on a backpack for off-road use by hikers and skiers or attached to scuba-diving gear for "Underwater Streetview (sic)." Streetview panoramas are linked together so that the viewer can change viewpoint by clicking forward and reverse buttons. They therefore create a 4-D touring effect. As part of the GEODE project ("Google Earth for Onsite and Distance Education"), we are experimenting with the use of Streetview imagery for geoscience education. Our web-based test application allows instructors to select locations for students to study. Students are presented with a set of questions or tasks that they must address by studying the panoramic imagery. Questions include identification of rock types, structures such as faults, and general geological setting. The student view is locked into Streetview mode until they submit their answers, whereupon the map and satellite views become available, allowing students to zoom out and verify their location on Earth. Student learning is scaffolded by automatic computerized feedback. There are lots of existing Streetview panoramas with rich geological content. Additionally, instructors and members of the general public can create panoramas, including 360° Photo Spheres, by stitching images taken with their mobiles devices and submitting them to Google for evaluation and hosting. A multi-thousand-dollar, multi-directional camera and mount can be purchased from DIY-streetview.com. This allows power users to generate their own high-resolution panoramas. A cheaper, 360° video camera is soon to be released according to geonaute.com. Thus there are opportunities for

  17. First Panoramic View From The Surface Of Mars

    NASA Technical Reports Server (NTRS)

    1976-01-01

    First panoramic view by Viking 1 from the surface of Mars. (Top): The out-of-focus spacecraft component toward left center is the housing for the Viking sample arm, which is not yet deployed. Parallel lines in the sky are an artifact and are not real features. However, the change of brightness from horizon towards zenith and towards the right (west) is accurately reflected in this picture, taken in late Martian afternoon. At the horizon to the left is a plateau-like prominence much brighter than the foreground material between the rocks. The horizon features are approximately three kilometers (1.8 miles) away. At left is a collection of fine-grained material reminiscent of sand dunes. The dark sinuous markings in left foreground are of unknown origin. Some unidentified shapes can be perceived on the hilly eminence at the horizon towards the right. Patches of bright sand can be discerned among the rocks and boulders in middle distance. In right fore-ground are two peculiarly shaped rocks which may possibly be ventifacts produced by wind abrasion on Mars. A horizontal cloud stratum can be made out halfway from the horizon to the top of the picture. (Bottom): At left is seen the low gain antenna for receipt of commands from the Earth. The projections on or near the horizon may represent the rims distant impact craters. In right foreground are color charts for Lander camera calibration, a mirror for the Viking magnetic properties experiment and part of a grid on the top of the Lander body. At upper right is the high-gain dish antenna for direct communication between landed space-craft and Earth. Toward the right edge is an array of smooth fine-grained material which shows some hint of ripple structure and may be the beginning of a large dune field off to the right of the picture, which joins with dunes seen at the top left in this 300 panoramic view. Some of the rocks appear to be undercut on one side and partially buried by drifting sand on the other.

  18. Mars Exploration Rover Athena Panoramic Camera (Pancam) investigation

    USGS Publications Warehouse

    Bell, J.F., III; Squyres, S. W.; Herkenhoff, K. E.; Maki, J.N.; Arneson, H.M.; Brown, D.; Collins, S.A.; Dingizian, A.; Elliot, S.T.; Hagerott, E.C.; Hayes, A.G.; Johnson, M.J.; Johnson, J. R.; Joseph, J.; Kinch, K.; Lemmon, M.T.; Morris, R.V.; Scherr, L.; Schwochert, M.; Shepard, M.K.; Smith, G.H.; Sohl-Dickstein, J. N.; Sullivan, R.J.; Sullivan, W.T.; Wadsworth, M.

    2003-01-01

    The Panoramic Camera (Pancam) investigation is part of the Athena science payload launched to Mars in 2003 on NASA's twin Mars Exploration Rover (MER) missions. The scientific goals of the Pancam investigation are to assess the high-resolution morphology, topography, and geologic context of each MER landing site, to obtain color images to constrain the mineralogic, photometric, and physical properties of surface materials, and to determine dust and aerosol opacity and physical properties from direct imaging of the Sun and sky. Pancam also provides mission support measurements for the rovers, including Sun-finding for rover navigation, hazard identification and digital terrain modeling to help guide long-term rover traverse decisions, high-resolution imaging to help guide the selection of in situ sampling targets, and acquisition of education and public outreach products. The Pancam optical, mechanical, and electronics design were optimized to achieve these science and mission support goals. Pancam is a multispectral, stereoscopic, panoramic imaging system consisting of two digital cameras mounted on a mast 1.5 m above the Martian surface. The mast allows Pancam to image the full 360?? in azimuth and ??90?? in elevation. Each Pancam camera utilizes a 1024 ?? 1024 active imaging area frame transfer CCD detector array. The Pancam optics have an effective focal length of 43 mm and a focal ratio f/20, yielding an instantaneous field of view of 0.27 mrad/pixel and a field of view of 16?? ?? 16??. Each rover's two Pancam "eyes" are separated by 30 cm and have a 1?? toe-in to provide adequate stereo parallax. Each eye also includes a small eight position filter wheel to allow surface mineralogic studies, multispectral sky imaging, and direct Sun imaging in the 400-1100 nm wavelength region. Pancam was designed and calibrated to operate within specifications on Mars at temperatures from -55?? to +5??C. An onboard calibration target and fiducial marks provide the capability

  19. Dental pathology in conventionally fed and pasture managed dairy cattle.

    PubMed

    Fadden, A N; Poulsen, K P; Vanegas, J; Mecham, J; Bildfell, R; Stieger-Vanegas, S M

    2016-01-01

    Healthy teeth are important in the first stages of digestion for dairy cattle, yet little is known about bovine dental disease. This study aimed to investigate dental pathology of dairy cattle in two parts. First dairy cattle cadaver heads (n=11) were examined at the time of culling. Second, the authors performed oral exams in cattle fed a total mixed ration (TMR) (n=200) and pasture-based (n=71) grazing cattle. Cadaver heads were imaged using radiography and computed tomography before gross dissection to study dental anatomy and pathology. The most prevalent dental abnormalities were excessive transverse ridging of the occlusal surface, the presence of diastemas and third molar dental overgrowths (M3DO) in cadaver heads. Average thickness of subocclusal dentine ranged from 3.5 mm to 5.8 mm in cheek teeth but was >10 mm in maxillary teeth with M3DO. Radiographic findings were compared with oral examinations in live cattle. Prevalence of M3DO upon oral examination was 19 per cent and 28 per cent in herds of cattle fed a TMR diet and 0 per cent in a herd of grazing cattle. Dental abnormalities are prevalent in dairy cattle but due to thin subocclusal dentine in the cheek teeth, established equine dental treatment methodology is not appropriate for bovine cheek teeth with the exception of those that have developed M3DO. PMID:26700105

  20. Dental MRI: Making the Invisible Visible

    PubMed Central

    Idiyatullin, Djaudat; Corum, Curt; Moeller, Steen; Prasad, Hari S.; Garwood, Michael; Nixdorf, Donald R.

    2011-01-01

    Introduction Clinical dentistry is in need of non-invasive and accurate diagnostic methods to better evaluate dental pathosis. The purpose of this work was to assess the feasibility of a recently developed magnetic resonance imaging (MRI) technique, called SWeep Imaging with Fourier Transform (SWIFT), to visualize dental tissues. Methods Three in vitro teeth, representing a limited range of clinical conditions of interest, imaged using a 9.4T system with scanning times ranging from 100 seconds to 25 minutes. In vivo imaging of a subject was performed using a 4T system with a 10-minute scanning time. SWIFT images were compared with traditional two-dimensional radiographs, three-dimensional cone-beam computed tomography (CBCT), gradient-echo MR imaging technique, and histological sections. Results A resolution of 100 microns was obtained from in vitro teeth. SWIFT also identified the presence and extent of dental caries and fine structures of the teeth, including cracks and accessory canals, which are not visible with existing clinical radiography techniques. Intraoral positioning of the radiofrequency coil produced initial images of multiple adjacent teeth at a resolution of 400 microns. Conclusions SWIFT MRI offers simultaneous three-dimensional hard and soft tissue imaging of teeth without the use of ionizing radiation. Further, it has the potential to image minute dental structures within clinically relevant scanning times. This technology has implications for endodontists since it offers a potential method to longitudinally evaluate teeth where pulp and root structures have been regenerated. PMID:21787482

  1. PROTON RADIOGRAPHY FOR AN ADVANCED HYDROTEST FACILITY

    SciTech Connect

    C. MORRIS

    2000-11-01

    Analysis of data from BNL experiment 933 is presented. Results demonstrate that proton radiography can meet many of the requirements for an Advanced Hydrotest Facility (AHF). Results for background, position resolution, metrology, quantitative radiography, material identification, and edge resolution are presented.

  2. ARG portable neutron radiography. Final report

    SciTech Connect

    Barton, J.P.

    1995-04-01

    In this report all available neutron radiographic data, including results of tests run at LANL, McClellan AFB, and University of Virginia, will be combined to outline specific transportable neutron radiography systems that could achieve the desired results as a complement to x-radiography capabilities for the Accident Response Group (ARG).

  3. INDUSTRIAL RADIOGRAPHY STUDENT GUIDE AND LABORATORY EXERCISES.

    ERIC Educational Resources Information Center

    Bureau of Adult, Vocational, and Technical Education (DHEW/OE), Washington, DC. Div. of Vocational and Technical Education.

    THIS INSTRUCTOR'S GUIDE TO AN 80-HOUR COURSE IN INDUSTRIAL RADIOGRAPHY IS COORDINATED WITH LESSONS IN THE STUDENT GUIDE AND LABORATORY EXERCISES AND IS BASED ON MATERIAL IN THE COURSE MANUAL, INDUSTRIAL RADIOGRAPHY. THE COURSE IS INTENDED TO TRAIN HIGH SCHOOL GRADUATES AS BEGINNING RADIOGRAPHERS WHO ARE EXPECTED TO BE ABLE TO EXTEND THEIR…

  4. Lesion detectability in digital radiography

    NASA Astrophysics Data System (ADS)

    Gagne, Robert M.; Boswell, Jonathan S.; Myers, Kyle J.; Peter, Guillaume

    2001-06-01

    The usefulness of Fourier-based measures of imaging performance has come into question for the evaluation of digital imaging systems. Figures of merit such as detective quantum efficiency are relevant for linear, shift-invariant systems with stationary noise. However, no digital imaging system is shift invariant, and realistic images do not satisfy the stationarity condition. Our methods for task- based evaluation of imaging systems, based on lesion detectability, do not require such assumptions. We have computed the performance of Hotelling and nonprewhitening matched-filter observers for the task of lesion detection in digital radiography.

  5. Radiography of Chaotically Moving Objects

    SciTech Connect

    Vavrik, Daniel; Jandejsek, Ivan; Dammer, Jiri; Holy, Tomas; Jakubek, Jan; Jakubek, Martin

    2007-11-26

    Radiography of moving objects is an advanced problem when the dynamic range of acquired radiograms is restricted by a limited exposition time. Exposition time has to be short to avoid image blurring due to object moving. It is possible to increase the dynamic range by summing short time radiograms set when the periodical object movement is presented as in the case of heart beating for instance. On the other hand a non periodical movement can be studied using tools of X-ray Digital Image Correlation technique. Short time radiograms are fitted into corresponding positions and consequently summed for higher data statistics as it is presented in this work.

  6. Infant dental care (image)

    MedlinePlus

    ... child to bed with a bottle of milk, juice, or sugar water. As the child grows, establishing proper dental hygiene will promote healthy teeth and gums which are essential to overall good health. Poor dental development, dental disease, and dental trauma ...

  7. Visually Coupled Systems (VCS): The Virtual Panoramic Display (VPD) System

    NASA Technical Reports Server (NTRS)

    Kocian, Dean F.

    1992-01-01

    The development and impact is described of new visually coupled system (VCS) equipment designed to support engineering and human factors research in the military aircraft cockpit environment. VCS represents an advanced man-machine interface (MMI). Its potential to improve aircrew situational awareness seems enormous, but its superiority over the conventional cockpit MMI has not been established in a conclusive and rigorous fashion. What has been missing is a 'systems' approach to technology advancement that is comprehensive enough to produce conclusive results concerning the operational viability of the VCS concept and verify any risk factors that might be involved with its general use in the cockpit. The advanced VCS configuration described here, was ruggedized for use in military aircraft environments and was dubbed the Virtual Panoramic Display (VPD). It was designed to answer the VCS portion of the systems problem, and is implemented as a modular system whose performance can be tailored to specific application requirements. The overall system concept and the design of the two most important electronic subsystems that support the helmet mounted parts, a new militarized version of the magnetic helmet mounted sight and correspondingly similar helmet display electronics, are discussed in detail. Significant emphasis is given to illustrating how particular design features in the hardware improve overall system performance and support research activities.

  8. Performance characteristics of a submarine panoramic infrared imaging sensor

    NASA Astrophysics Data System (ADS)

    Nichols, J. M.; Waterman, J. R.; Menon, Raghu; Devitt, John

    2010-04-01

    A high-resolution mid-wave infrared panoramic periscope sensor system has been developed. The sensor includes a catadioptric optical system that provides a 360° horizontal azimuth by -10° to +30° elevation field of view without requiring moving components (e.g. rotating mirrors). The focal plane is a 2048 x 2048, 15μm pitch InSb detector operating at 80K. An on-board thermo-electric reference source allows for real-time nonuniformity correction using the two-point correction method. The entire system (detector-dewar assembly, cooler, electronics and optics) is packaged to fit in an 8" high, 6.5" diameter volume. This work describes both the system optics and electronics and presents sample imagery. We also discuss the sensor's radiometric performance, quantified by the NEDT, as a function of key system parameters. The ability of the system to resolve targets as a function of imaged spatial frequency is also presented.

  9. Assessment of panoramic and conventional night vision goggles

    NASA Astrophysics Data System (ADS)

    Thorndycraft, David

    2003-09-01

    This paper presents results obtained during a flight evaluation of Night Vision Devices (NVDs) equipped with a symbology injection capability. The NVDs used represented both conventional and wide (Panoramic) Field of View Night Vision Goggle (PNVG) systems. The evaluation was conducted at the National Research Council of Canada Bell 205 Flying Simulator under the auspices of the Technical Co-operation Programme. 6 Pilots from 4 nations participated in the trial and some 36 hours of flight data and pilot performance were recorded. The metrics used to evaluate Pilot performance included conventional Visual Cue Ratings, estimates of workload, and objective measures obtained through advanced data-analysis techniques. The trial used both conventional ADS-33D manoeuvres and a novel 'Racetrack" course. The paper concludes that although PNVG compare favourably with NVGs the clarity of image currently available in standard NVGs surpasses that of the PNVG and negates some of the advantages gained by the wider Field of View. The manoeuvres favoured by the NVG include those where a high degree of foveal attention demanding processing is being performed, for example navigation tasks. The manoeuvres favoured by the PNVG include those where a more automatic peripheral processing is being performed, for example in reducing drift in the hover.

  10. Real-time panoramic infrared imaging system based on FPGA

    NASA Astrophysics Data System (ADS)

    Zhang, Hao-Jun; Shen, Yong-Ge

    2010-11-01

    During the past decades, signal processing architecture, which is based on FPGA, conventional DSP processor and host computer, is popular for infrared or other electro-optical systems. With the increasing processing requirement, the former architecture starts to show its limitation in several respects. This paper elaborates a solution based on FPGA for panoramic imaging system as our first step of upgrading the processing module to System-on-Chip (SoC) solution. Firstly, we compare this new architecture with the traditional to show its superiority mainly in the video processing ability, reduction in the development workload and miniaturization of the system architecture. Afterwards, this paper provides in-depth description of this imaging system, including the system architecture and its function, and addresses several related issues followed by the future development. FPGA has developed so rapidly during the past years, not only in silicon device but also in the design flow and tools. In the end, we briefly present our future system development and introduce those new design tools to make up the limitation of the traditional FPGA design methodology. The advanced design flow through Simulink and Xilinx System Generator (Sysgen) has been elaborated, which enables engineers to develop sophisticated DSP algorithms and implement them in FPGA more efficiently. It is believed that this new design approach can shorten system design cycle by allowing rapid prototyping and refining design process.

  11. Third of three panoramic views of North Base as seen ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Third of three panoramic views of North Base as seen from top of Building 4500, Control Tower. View looks west (268°) at ancillary structures surrounding Building 4505. In immediate foreground is Building 4499 Loading Ramp. To the far upper left is Building 4497 Guard House, adjacent to Building 4496 Security Facility. At the extreme right of the view is the chimney and western corner of Building 4505 to which is attached a large light-colored wing used as offices and workspaces; to the immediate southwest of this wing stands Building 4498 Supply Warehouse. In the background, just above Building 4498 in view, stands Building 4494 Cafeteria. The round drum to the right of Building 4494 is Building 4503, a 500,000 gallon water tank which supplies the firefighting system; to the immediate right of the tank is Building 4504 Deluge Water Pumping Station which contains large pumps for firefighting. Just visible above the water tank is Building 4493 Gymnasium. - Edwards Air Force Base, North Base, North Base Road, Boron, Kern County, CA

  12. Indoor Positioning and Navigation Based on Control Spherecal Panoramic Images

    NASA Astrophysics Data System (ADS)

    Huang, Tsung-Che; Tseng, Yi-Hsing

    2016-06-01

    Continuous indoor and outdoor positioning and navigation is the goal to achieve in the field of mobile mapping technology. However, accuracy of positioning and navigation will be largely degraded in indoor or occluded areas, due to receiving weak or less GNSS signals. Targeting the need of high accuracy indoor and outdoor positioning and navigation for mobile mapping applications, the objective of this study is to develop a novel method of indoor positioning and navigation with the use of spherical panoramic image (SPI). Two steps are planned in the technology roadmap. First, establishing a control SPI database that contains a good number of well-distributed control SPIs pre-acquired in the target space. A control SPI means an SPI with known exterior orientation parameters, which can be solved with a network bundle adjustment of SPIs. Having a control SPI database, the target space will be ready to provide the service of positioning and navigation. Secondly, the position and orientation of a newly taken SPI can be solved by using overlapped SPIs searched from the control SPI database. The method of matching SPIs and finding conjugate image features will be developed and tested. Two experiments will be planned and conducted in this paper to test the feasibility and validate the test results of the proposed methods. Analysis of appropriate number and distribution of needed control SPIs will also be included in the experiments with respect to different test cases.

  13. 2D and 3D visualization methods of endoscopic panoramic bladder images

    NASA Astrophysics Data System (ADS)

    Behrens, Alexander; Heisterklaus, Iris; Müller, Yannick; Stehle, Thomas; Gross, Sebastian; Aach, Til

    2011-03-01

    While several mosaicking algorithms have been developed to compose endoscopic images of the internal urinary bladder wall into panoramic images, the quantitative evaluation of these output images in terms of geometrical distortions have often not been discussed. However, the visualization of the distortion level is highly desired for an objective image-based medical diagnosis. Thus, we present in this paper a method to create quality maps from the characteristics of transformation parameters, which were applied to the endoscopic images during the registration process of the mosaicking algorithm. For a global first view impression, the quality maps are laid over the panoramic image and highlight image regions in pseudo-colors according to their local distortions. This illustration supports then surgeons to identify geometrically distorted structures easily in the panoramic image, which allow more objective medical interpretations of tumor tissue in shape and size. Aside from introducing quality maps in 2-D, we also discuss a visualization method to map panoramic images onto a 3-D spherical bladder model. Reference points are manually selected by the surgeon in the panoramic image and the 3-D model. Then the panoramic image is mapped by the Hammer-Aitoff equal-area projection onto the 3-D surface using texture mapping. Finally the textured bladder model can be freely moved in a virtual environment for inspection. Using a two-hemisphere bladder representation, references between panoramic image regions and their corresponding space coordinates within the bladder model are reconstructed. This additional spatial 3-D information thus assists the surgeon in navigation, documentation, as well as surgical planning.

  14. Validation of a computed radiography device to monitor the HIV-1 RNase H activity

    NASA Astrophysics Data System (ADS)

    Esposito, F.; Fanti, V.; Marzeddu, R.; Randaccio, P.; Tramontano, E.; Zinzula, L.

    2009-08-01

    A commercially available computed radiography (CR) system for dental radiography was used to produce images from radiolabeled polyacrilamide gel electrophoresis (PAGE) assays. Typically, similar investigations require specific and expensive autoradiography devices. The CR unit was characterized in terms of sensitivity and fading by means of a 90Sr source that well simulates the experimental conditions, and then used for quantitative analyses of the human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) polymerase-independent ribonuclease H (RNase H) activity monitored by PAGE analysis. The results showed that the present methodology allows quantifying effectively the RNase H catalyses and that the obtained data are in good agreement with previous reference works. Finally, in order to further validate the present method in terms of relationship between enzyme activity, the rate of products formation and signal intensity, a PAGE analyses of the HIV-1 RNase H inhibition by the known diketo acid derivative RDS1643 was carried out.

  15. Dental education in Colombia

    PubMed Central

    Jaramillo, Jorge A.; Pulido, Jairo H. Ternera; Núñez, Jaime A. Castro; Bird, William F.; Komabayashi, Takashi

    2014-01-01

    This article describes Colombia's development of formal dentistry, its dental school system, curriculum, and dental licensure, and current issues in oral health care. In 1969, there were only 4 dental schools in Colombia; at this writing there are 21. Five dental schools are public and the other 16 are private. Nearly all classes are conducted in Spanish. Undergraduate pre-dental coursework is not a prerequisite for dental school in Colombia. To obtain licensure, Colombian dental students must complete 5 years of study in dental school, earn a diploma, and work for the government for 1 year. There are approximately 41,400 dentists in Colombia, and the number is increasing quickly. However, the unemployment rate among dentists is very high, even though graduation from dental school is extremely difficult. Although the 1,100:1 ratio of citizens to dentists is considered satisfactory, access to dental care is limited due to the high rate of poverty. PMID:20339245

  16. Effective appropriate use of dental remains and forensic DNA testing for personal identity confirmation.

    PubMed

    Ohira, Hiroshi; Yamamuro, Yoshio; Kitagawa, Yuka; Nakagawa, Kimiko; Yamamoto, Isao; Yamada, Yoshihiro

    2009-04-01

    Two severely burned human male bodies, possibly those of a parent and child, were recovered from the scene of a house fire and positive identification of the bodies was accomplished. This report describes the appropriate use of effective identification methods that made this possible. Identification of a body involves comparison of antemortem and postmortem X-ray films or dental records. In cases of poorly preserved dental remains, or in the absence of antemortem dental records, forensic DNA testing can be done. In the present case the male thought to be the son was identified from an antemortem panoramic X-ray film provided by the family dentist, which matched every significant detail in the body. On the other hand, forensic DNA testing of a sample obtained from the father's burned body was done in comparison with a swab obtained from his older brother, as the victim had no dental records for the 5 years before his death. This was able to confirm his identity. Thus positive identification was established through a combination of these methods. Although positive identification from dental records is rapid and certain, it requires antemortem dental records. If these are not available, forensic DNA testing should be attempted. In laboratories of forensic odontology, facilities for identity confirmation from both dental characteristics and forensic DNA testing should be made available. PMID:19269216

  17. Direct detector radiography versus dual reading computed radiography: feasibility of dose reduction in chest radiography.

    PubMed

    Gruber, Michael; Uffmann, Martin; Weber, Michael; Prokop, Mathias; Balassy, Csilla; Schaefer-Prokop, Cornelia

    2006-07-01

    The image quality of dual-reading computed radiography and dose-reduced direct radiography of the chest was compared in a clinical setting. The study group consisted of 50 patients that underwent three posteroanterior chest radiographs within minutes, one image obtained with a dual read-out computed radiography system (CR; Fuji 5501) at regular dose and two images with a flat panel direct detector unit (DR; Diagnost, Philips). The DR images were obtained with the same and with 50% of the dose used for the CR images. Images were evaluated in a blinded side-by-side comparison. Eight radiologists ranked the visually perceivable difference in image quality using a three-point scale. Then, three radiologists scored the visibility of anatomic landmarks in low and high attenuation areas and image noise. Statistical analysis was based on Friedman tests and Wilcoxon rank sum tests at a significance level of P<0.05. DR was judged superior to CR for the delineation of structures in high attenuation areas of the mediastinum even when obtained with 50% less dose (P<0.001). The visibility of most pulmonary structures was judged equivalent with both techniques, regardless of acquisition dose and speed level. Scores for image noise were lower for DR compared with CR, with the exception of DR obtained at a reduced dose. Thus, in this clinical preference study, DR was equivalent or even superior to the most modern dual read-out CR, even when obtained with 50% dose. A further dose reduction does not appear to be feasible for DR without significant loss of image quality. PMID:16404566

  18. Dental age assessment among Tunisian children using the Demirjian method

    PubMed Central

    Aissaoui, Abir; Salem, Nidhal Haj; Mougou, Meryam; Maatouk, Fethi; Chadly, Ali

    2016-01-01

    Context: Since Demirjian system of estimating dental maturity was first described, many researchers from different countries have tested its accuracy among diverse populations. Some of these studies have pointed out a need to determine population-specific standards. Aim: The aim of this study is to evaluate the suitability of the Demirjian's method for dental age assessment in Tunisian children. Materials and Methods: This is a prospective study previously approved by the Research Ethics Local Committee of the University Hospital Fattouma Bourguiba of Monastir (Tunisia). Panoramic radiographs of 280 healthy Tunisian children of age 2.8–16.5 years were examined with Demirjian method and scored by three trained observers. Statistical Analysis Used: Dental age was compared to chronological age by using the analysis of variance (ANOVA) test. Cohen's Kappa test was performed to calculate the intra- and inter-examiner agreements. Results: Underestimation was seen in children aged between 9 and 16 years and the range of accuracy varied from −0.02 to 3 years. The advancement in dental age as determined by Demirjian system when compared to chronological age ranged from 0.3 to 1.32 year for young males and from 0.26 to 1.37 year for young females (age ranged from 3 to 8 years). Conclusions: The standards provided by Demirjian for French-Canadian children may not be suitable for Tunisian children. Each population of children may need their own specific standard for an accurate estimation of chronological age. PMID:27051223

  19. Atypical Forensic Dental Identifications.

    PubMed

    Cardoza, Anthony R; Wood, James D

    2015-06-01

    Forensic dental identification specialists are typically the last conventional option for postmortem identification. Forensic dental identification is most often accomplished by comparing radiographs of the decedent's teeth with the dental radiographs obtained from the dentist of the suspected victim. Unfortunately, antemortem dental radiographs are not always available. When presented with this challenge, the authors of this article have been successful in completing identifications using means other than dental radiographic comparison. PMID:26126345

  20. Dental stem cell patents.

    PubMed

    Morsczeck, Christian; Frerich, Bernhard; Driemel, Oliver

    2009-01-01

    A complex human tissue harbors stem cells that are responsible for its maintenance or repair. These stem cells have been isolated also from dental tissues such as the periodontal ligament, dental papilla or dental follicle and they may offer novel applications in dentistry. This following review summarizes patents about dental stem cells for dental tissue engineering and considers their value for regenerative dentistry. PMID:19149737

  1. Predictive variables derived from panoramic radiographs for impacted maxillary cuspids treated with easy cuspid system.

    PubMed

    Caprioglio, Alberto; Finazzi, Francesca; Mortellaro, Carmen; Mangano, Carlo; Lucchina, Alberta Greco; Mangano, Francesco; Levrini, Luca

    2015-05-01

    The aim of the current study was to find, by means of panoramic radiographs, a viable statistical method to forecast the duration of orthodontic traction of impacted maxillary cuspids. The treatment sample consisted of 51 palatal impacted cuspids (19 unilateral and 32 bilateral) in 35 patients (aged between 10.5 and 17.5 y) with a cervical vertebral maturation between cervical stage 1 and 4. Each patient underwent the same combined surgical-orthodontic technique. Anamnestic data as well as pretreatment panoramic radiograph and cephalogram with European Board of Orthodontics analysis were recorded for each case. Eight radiographic indicators were derived from panoramic films to define the reliable position of the impacted cuspid. Multiple regression analysis was used. All cuspids were successfully treated with an average traction time of 99 days (range, 33-188 d). The pretreatment radiographic features assessed on the panoramic radiographs did not significantly affect the duration of traction. The formula based on α angle, d1 distance, and S sector forecasted an average traction time of 123 days (range, 63-210 d), which is longer than the real time. No relevant correlations were found between orthodontic traction time and pretreatment radiograph parameters derived from panoramic film at the beginning of the treatment. The classic formula elaborated by Crescini could not be applied to the patients of this study, who were treated with the Easy Cuspid method. PMID:25850874

  2. Global and Local Panoramic Views for Gastroscopy: An Assisted Method of Gastroscopic Lesion Surveillance.

    PubMed

    Liu, Jiquan; Wang, Bin; Hu, Weiling; Sun, Pan; Li, Jieyu; Duan, Huilong; Si, Jianmin

    2015-09-01

    Gastroscopy plays an important role in the diagnosis of gastric disease. In this paper, we develop an image panoramic system to assist endoscopists in improving lesion surveillance and reducing many of the tedious operations associated with gastroscopy. The constructed panoramic view has two categories: 1) the local view broadens the endoscopist's field of view in real time. Combining with the original gastroscopic video, this mosaicking view enables the endoscopist to diagnose the lesion comprehensively; 2) the global view constructs a large-area panoramic scene of the internal gastric surface, which can be used for intraoperative surgical navigation and postoperative scene review. Due to the irregular texture and inconsistent reflection of the gastric internal surface, common registration methods cannot accurately stitch this surface. Thereby, a six degree of freedom position tracking endoscope is devised to accommodate for the accumulated mosaicking error and provide efficient mosaicking results. For the global view, a dual-cube constraint model and a Bundle Adjustment algorithm are incorporated to deal with the mosaicking error caused by the irregular inflation and nonrigid deformation of the stomach. Moreover, texture blending and frame selection schemes are developed to make the mosaicking results feasible in real-clinical applications. The experimental results demonstrate that our system performs with a speed of 7.12 frames/s in a standard computer environment, and the mosaicking mean error is 0.43 mm for local panoramic view and 3.71 mm for global panoramic view. PMID:25910000

  3. [The evaluation of the marginal bone height on traditional and digitized panoramic radiographs].

    PubMed

    Larsen, T S; Regli, P E

    1989-01-01

    The aim of the present study was to compare original and digitized panoramic radiographs (with a 512 X 512 digitization matrix) for the assessment of alveolar bone loss using intraoral radiographs as a reference. Intraoral radiographs of 2+, +5, and 6- and an orthopantomogram were obtained from each of 55 patients. Alveolar bone level was measured on the intraoral, the original panoramic, and the digitized panoramic radiographs using a Schei ruler as percentage of bone left from the cemento-enamel junction to the apex. Mean values between the separate observations of the two authors were used. A statistically significant reduction in bone level was observed when assessed by the panoramic methods compared to the intraoral radiographs (P less than 0.01 for all tooth groups). Similarly a significant reduction was observed in the digitized panoramic radiographs compared to the originals (P less than 0.05) except for the molar region. The results indicate that the 512 X 512 spatial resolution is not sufficient for the digitization of extraoral radiographs when fine-detail diagnostics are needed. It is suggested that extraoral radiographs are digitized in segments when working with this matrix. PMID:2623591

  4. Dental hyponatraemia.

    PubMed

    Simpson, R M

    2011-08-01

    A 14-year-old girl developed dental pain and was treated for acute infected pulpitis of her right upper lateral incisor with drilling and filling. The pain continued and was helped by analgesia, sucking ice cubes and drinking cold water. Forty-eight hours later, she became confused and disoriented. She started to vomit and complained of headache. Investigations revealed hyponatraemia with normal serum potassium levels and initially normal urinary sodium excretion. Over the next 24 hours, she passed 5.45 L of urine and her serum sodium rose from 125 to 143 mmol/L. Self-induced water intoxication has been described during drinking games and initiation ceremonies, but this would appear to an unusual cause. Conservative management proved successful in allowing this girl to recover without sequelae. PMID:21873727

  5. Subjective image quality comparison between two digital dental radiographic systems and conventional dental film

    PubMed Central

    Ajmal, Muhammed; Elshinawy, Mohamed I.

    2014-01-01

    Objectives Digital radiography has become an integral part of dentistry. Digital radiography does not require film or dark rooms, reduces X-ray doses, and instantly generates images. The aim of our study was to compare the subjective image quality of two digital dental radiographic systems with conventional dental film. Materials & methods A direct digital (DD) ‘Digital’ system by Sirona, a semi-direct (SD) digital system by Vista-scan, and Kodak ‘E’ speed dental X-ray films were selected for the study. Endodontically-treated extracted teeth (n = 25) were used in the study. Details of enamel, dentin, dentino-enamel junction, root canal filling (gutta percha), and simulated apical pathology were investigated with the three radiographic systems. The data were subjected to statistical analyzes to reveal differences in subjective image quality. Results Conventional dental X-ray film was superior to the digital systems. For digital systems, DD imaging was superior to SD imaging. Conclusion Conventional film yielded superior image quality that was statistically significant in almost all aspects of comparison. Conventional film was followed in image quality by DD, and SD provided the lowest quality images. Conventional film is still considered the gold standard to diagnose diseases affecting the jawbone. Recommendations Improved software and hardware for digital imaging systems are now available and these improvements may now yield images that are comparable in quality to conventional film. However, we recommend that studies still use more observers and other statistical methods to produce ideal results. PMID:25382946

  6. Panoramic Views of Cluster Evolution Since z = 3

    NASA Astrophysics Data System (ADS)

    Kodama, Tadayuki; Tanaka, M.; Tanaka, Ichi; Kajisawa, M.

    2007-05-01

    We have been conducting PISCES project (Panoramic Imaging and Spectroscopy of Cluster Evolution with Subaru) with making use of the wide-field imaging capability of Subaru. Our motivations are first to map out large scale structure and local environment of galaxies therein, and then to investigate the variation in galaxy properties as a function of environment and mass. We have completed multi-colour imaging of 8 distant clusters between 0.42) by wide-field near-infrared imaging of proto-clusters around radio loud galaxies, some of which are known to show a large number of Lya/Ha emitters at the same redshift of the radio galaxies. We have seen clear excess of near-infrared selected galaxies (including DRG) around many of the radio galaxies, suggesting that these are indeed likely to be proto-clusters with not only young emitters but also evolved populations. Spatial distribution of such NIR selected galaxies is filamentary and track similar structures traced by the emitters, but showing little individual overlap. The above two wide-field studies of dense environments and their surroundings will tell us galaxy evolution during the course of cluster assembly over more than 80 per cent of the age of the Universe.

  7. Panoramic Views of the Landing site from Sagan Memorial Station

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Each of these panoramic views is a controlled mosaic of approximately 300 IMP images covering 360 degrees of azimuth and elevations from approximately 4 degrees above the horizon to 45 degrees below it. Simultaneous adjustment of orientations of all images has been performed to minimize discontinuities between images. Mosaics have been highpass-filtered and contrast-enhanced to improve discrimination of details without distorting relative colors overall.

    TOP IMAGE: Enhanced true-color image created from the 'Gallery Pan' sequence, acquired on sols 8-10 so that local solar time increases nearly continuously from about 10:00 at the right edge to about 12:00 at the left. Mosaics of images obtained by the right camera through 670 nm, 530 nm, and 440 nm filters were used as red, green and blue channels. Grid ticks indicate azimuth clockwise from north in 30 degree increments and elevation in 15 degree increments.

    BOTTOM IMAGE: Anaglyphic stereoimage created from the 'monster pan' sequence, acquired in four sections between about 8:30 and 15:00 local solar time on sol 3. Mosaics of images obtained through the 670 nm filter (left camera) and 530 and 440 nm filters (right camera) were used where available. At the top and bottom, left- and right-camera 670 nm images were used. Part of the northern horizon was not imaged because of the tilt of the lander. This image may be viewed stereoscopically through glasses with a red filter for the left eye and a cyan filter for the right eye.

    NOTE: original caption as published in Science Magazine

    Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is a division of the California Institute of Technology (Caltech).

  8. PanoramicData: Data Analysis through Pen & Touch.

    PubMed

    Zgraggen, Emanuel; Zeleznik, Robert; Drucker, Steven M

    2014-12-01

    Interactively exploring multidimensional datasets requires frequent switching among a range of distinct but inter-related tasks (e.g., producing different visuals based on different column sets, calculating new variables, and observing the interactions between sets of data). Existing approaches either target specific different problem domains (e.g., data-transformation or data-presentation) or expose only limited aspects of the general exploratory process; in either case, users are forced to adopt coping strategies (e.g., arranging windows or using undo as a mechanism for comparison instead of using side-by-side displays) to compensate for the lack of an integrated suite of exploratory tools. PanoramicData (PD) addresses these problems by unifying a comprehensive set of tools for visual data exploration into a hybrid pen and touch system designed to exploit the visualization advantages of large interactive displays. PD goes beyond just familiar visualizations by including direct UI support for data transformation and aggregation, filtering and brushing. Leveraging an unbounded whiteboard metaphor, users can combine these tools like building blocks to create detailed interactive visual display networks in which each visualization can act as a filter for others. Further, by operating directly on relational-databases, PD provides an approachable visual language that exposes a broad set of the expressive power of SQL including functionally complete logic filtering, computation of aggregates and natural table joins. To understand the implications of this novel approach, we conducted a formative user study with both data and visualization experts. The results indicated that the system provided a fluid and natural user experience for probing multi-dimensional data and was able to cover the full range of queries that the users wanted to pose. PMID:26356925

  9. Radiographic evaluation of the maxillary sinus prior to dental implant therapy: A comparison between two-dimensional and three-dimensional radiographic imaging

    PubMed Central

    Fung, Karen; Thacker, Sejal; Mahdian, Mina; Jadhav, Aniket; Schincaglia, Gian Pietro

    2015-01-01

    Purpose This study was performed to evaluate the diagnostic efficacy of panoramic radiography and cone-beam computed tomography (CBCT) in detecting sinus pathology. Materials and Methods This study was based on a retrospective evaluation of patients who had undergone both a panoramic radiograph and a CBCT exam. A total of 100 maxillary sinuses were evaluated. Four examiners with various levels of expertise evaluated the images using a five-point scoring system. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic efficacy of the two modalities. The image analysis was repeated twice, with at least two weeks between the evaluation sessions. Interobserver reliability was assessed using Cronbach's alpha, and intraobserver reliability was assessed using Cohen's kappa. Results Maxillary sinus pathology was detected in 72% of the patients. High interobserver and intraobserver reliability were observed for both imaging modalities and among the four examiners. Statistical analyses using ROC curves demonstrated that the CBCT images had a larger area under the curve (0.940) than the panoramic radiographs (0.579). Conclusion Three-dimensional evaluation of the sinus with CBCT was significantly more reliable in detecting pathology than panoramic imaging. PMID:26389059

  10. Interobserver agreement on the diagnosis of carotid artery calcifications on panoramic radiographs

    PubMed Central

    Yoon, Suk-Ja; Shim, Sung-Kyun; Kang, Byung-Cheol; Lim, Hoi-Jeong; Kim, Min-Seok; Kim, Sun-Hun

    2014-01-01

    Purpose This study was performed to investigate the interobserver agreement on the detection of carotid artery calcifications on panoramic radiographs. Materials and Methods This study consisted of panoramic radiographs acquired from 634 male patients of the age of 50 years or older. Having excluded carotids of no diagnostic quality, 1008 carotids from the panoramic radiographs of the patients were interpreted by two oral and maxillofacial radiologists independently for the presence of carotid artery calcifications. Statistical analysis was used to calculate the interobserver agreement. Results Interobserver agreement was obtained for 932 carotids (92.4%). Inconsistent interpretation of 76 carotids (7.5%) between the two observers was found. Cohen's kappa value was 0.688 (p<0.001). Conclusion The probability of a match between the two observers was substantially high. PMID:24944963

  11. Biologically Motivated Novel Localization Paradigm by High-Level Multiple Object Recognition in Panoramic Images

    PubMed Central

    Kim, Sungho; Shim, Min-Sheob

    2015-01-01

    This paper presents the novel paradigm of a global localization method motivated by human visual systems (HVSs). HVSs actively use the information of the object recognition results for self-position localization and for viewing direction. The proposed localization paradigm consisted of three parts: panoramic image acquisition, multiple object recognition, and grid-based localization. Multiple object recognition information from panoramic images is utilized in the localization part. High-level object information was useful not only for global localization, but also for robot-object interactions. The metric global localization (position, viewing direction) was conducted based on the bearing information of recognized objects from just one panoramic image. The feasibility of the novel localization paradigm was validated experimentally. PMID:26457323

  12. Metal thickness measurements using radiography

    NASA Astrophysics Data System (ADS)

    Achrekar, P. M.

    1986-04-01

    The present invention relates broadly to a radiographic inspection technique, and in particular to a metal thickness measurement method using radiography. The localized areas wherein the effective metal thickness is less than the minimum that is required for radiation shielding and which can render a shielding enclosure functionless, is readily determined. The invention comprises a process for assuring metal thickness in small regions. The actual metal thickness of small regions can be verified by comparing the optical densities of sections of the metal i.e., stepwedge. A comparator microphotometer, which compares optical densities of spectrum lines from spectrophotometers, compares the optical density of spectrum lines on an exposed spectrum plate (metal under test) with a standard plate (stepwedge).

  13. New developments in flash radiography

    NASA Astrophysics Data System (ADS)

    Mattsson, Arne

    2007-01-01

    The paper will review some of the latest developments in flash radiography. A series of multi anode tubes has been developed. These are tubes with several x-ray sources within the same vacuum enclosure. The x-ray sources are closely spaced, to come as close as possible to a single source. The x-ray sources are sequentially pulsed, at times that can be independently chosen. Tubes for voltages in the range 150 - 500 kV, with up to eight x-ray sources, will be described. Combining a multi anode tube with an intensified CCD camera, will make it possible to generate short "x-ray movies". A new flash x-ray control system has been developed. The system is operated from a PC or Laptop. All parameters of a multi channel flash x-ray system can be remotely set and monitored. The system will automatically store important operation parameters.

  14. [Dental records and responsibility].

    PubMed

    Brands, W G

    2006-03-01

    Dental records are more than a small part of the bookkeeping. In most dental practises, keeping records is the task of a dental assistant. In civil court, the dentist is in most countries liable for the mistakes of his employees. In disciplinary court however there may be doubt whether the dentist is responsible for the mistakes of his assistant. Contrary to their American colleagues, Dutch dental assistants and dental hygienists cannot be summoned before a disciplinary court. As these para-medics perform more and more dental treatment, independently or after delegation, they should be assigned there own disciplinary responsibility. PMID:16566401

  15. Extraoral periapical radiography: an alternative approach to intraoral periapical radiography.

    PubMed

    Kumar, Rahul; Khambete, Neha; Priya, Ekta

    2011-12-01

    It is difficult to take intraoral radiographs in some patients who are intolerable to place the film in their mouth. For these patients, Newman and Friedman recommended a new technique of extraoral film placement. Here we report various cases that diagnostic imaging was performed in patients using the extraoral periapical technique. This technique was used to obtain the radiographs for the patients with severe gag reflex, pediatric dental patients, and patients with restricted mouth opening. This technique can be recommended as an alternative to conventional intraoral periapical technique in cases where intraoral film placement is difficult to achieve. PMID:22232725

  16. Handling qualities comparison of panoramic night vision goggles and 46-deg. night vision goggles

    NASA Astrophysics Data System (ADS)

    Craig, Gregory; Jennings, Sion; Thorndycraft, David

    2003-09-01

    Night Vision Goggles allow the user to see in extremely low illumination levels but the visual information provided by Night Vision Goggles has a limited field-of-view that diminishes handling-qualities in the night flying environment. Panoramic Night Vision Goggles were designed to correct this problem by providing a 100° horizontal field-of-view which is larger than currently used Night Vision Goggles. However, in the first generation Panoramic Night Vision Goggle, the improved field of view came at the cost of diminished resolution, contrast and central overlap area when compared to conventional Night Vision Goggles. This paper describes an evaluation that was conducted in the variable stability NRC Bell-205 helicopter to examine the influence on system handling qualities of the Panoramic Night Vision Goggles and a 46° field-of-view UK Night Vision Goggle. Five pilots flew the ADS-33D hover, sidestep and pirouette manoeuvres in simulated night conditions with the UK Night Vision Goggle and the Panoramic Night Vision Goggle. Both subjective and objective measures of task performance were obtained. Handling-qualities ratings showed the pirouette was performed better with the Panoramic Night Vision Goggles. This was the only manoeuvre where there was a clear-cut handling qualities improvement when using the Panoramic Night Vision Goggles. Other manoeuvres such as the sidestep and hover did not show definitive handling qualities rating differences between the two Night Vision Goggle types. The flight test results were interpreted in terms of the design trade-offs of the two night vision systems, with regard to the different acuity, binocular overlaps and fields-of-view.

  17. [The inaccuracy of the panoramic radiograph as a tool to determine tooth inclination].

    PubMed

    Brezniak, N; Birnboim-Blau, G; Bar-Hama, P; Zoizner, R; Dinbar, A; Wasserstein, A

    2012-01-01

    The panoramic radiograph is one of the most common radiographs in orthodontics. It is sometimes used as an aid for the decision which teeth should be extracted as part of the individual treatment plan. When treating patients with clear plates (for example, Invisalign), it is very important to know the inclination direction of the involved teeth. Tipping is more predictable and it takes less time than bodily movement. The objective of this paper is to demonstrate the limitations of the panoramic radiograph in the decision making process related extraction in orthodontics. An eleven years old girl with lower anterior crowding of about 5 mm was examined prior to her orthodontic treatment. One possible treatment plan, in order to relieve the crowding, was to extract two lower bicuspids. The other treatment plan was to extract one lower incisor. Clinically, both cuspids were acutely tipped mesially, but were imaged uprighted and parallel to their adjacent teeth in the panoramic radiograph. In order to better understand the cuspids position, a model of the lower arch was prepared, with a similar malocclusion demonstrated by the patient. In the model, the cuspids' metal teeth, invested in wax, were mesially angulated. A panoramic radiograph of the model was then taken. The radiograph of the model shows a parallel position of the incisors, the cuspids and the bicuspids, exactly as was shown in the patient's radiograph. It has been demonstrated that there is a discrepancy between the actual position of the teeth and roots and their position in the panoramic radiograph, especially in the mesiodistal angulation. It was concluded that we should be very cautious when trying to interpret the panoramic radiograph as a tool for root parallelism, and remember the inherent image distortions. This is especially true before deciding which teeth will be extracted, on the basis of "incorrect" tooth angulation. PMID:22991875

  18. A Comparison of the AVS-9 and the Panoramic Night Vision Goggles During Rotorcraft Hover and Landing

    NASA Technical Reports Server (NTRS)

    Szoboszlay, Zoltan; Haworth, Loran; Simpson, Carol

    2000-01-01

    A flight test was conducted to assess any differences in pilot-vehicle performance and pilot opinion between the use of a current generation night vision goggle (the AVS-9) and one variant of the prototype panoramic night vision goggle (the PNVGII). The panoramic goggle has more than double the horizontal field-of-view of the AVS-9, but reduced image quality. Overall the panoramic goggles compared well to the AVS-9 goggles. However, pilot comment and data are consistent with the assertion that some of the benefits of additional field-of-view with the panoramic goggles were negated by the reduced image quality of the particular variant of the panoramic goggles tested.

  19. 360  deg full-parallax light-field display using panoramic camera.

    PubMed

    Su, Chen; Zhou, Xinxin; Li, Haifeng; Yang, Qing; Wang, Zhechao; Liu, Xu

    2016-06-10

    One of the common approaches to achieving vertical parallax for the horizontal-parallax-only light-field display is to introduce the viewer-tracking method. A panoramic camera is assembled in a 360 deg scanning light-field display system for the full-parallax demand in this study, wherein the image generation algorithm is improved to be sensitive to multiple viewer positions, and the tracking and rendering are processed in real time. The horizontal-parallax-only light-field display using a panoramic camera is determined to be able to achieve smooth and consecutive full-parallax performance for multiple viewers in a 360 deg range. PMID:27409032

  20. Design of high resolution panoramic endoscope imaging system based on freeform surface

    NASA Astrophysics Data System (ADS)

    Liu, Qun; Bai, Jian; Luo, Yujie

    2016-01-01

    This paper introduces a novel endoscope design based on the panoramic annular staring imaging technology. This design utilizes a single optical system to realize both panoramic observation and local high resolution on a single sensor. The freeform surface is employed to improve the image quality and reduce system volume. The design results based on the commercial optical design software package ZEMAX, indicate that this optical system is able to acquire an excellent image quality with a modulation transfer function above 0.6. Compared with the traditional ones, this novel endoscope design with wide FOV is likely to decrease the diagnostic time dramatically and improve the lesion detect rate considerably.

  1. Dental Auxiliary Occupations. Interim Report.

    ERIC Educational Resources Information Center

    Kingston, Richard D.

    As part of a dental auxiliaries project, a Dental Auxiliary National Technical Advisory Committee was established, and its major undertaking was to assist in the development of a functional inventory for each of the three dental auxiliary occupations (dental assisting, dental hygiene, and dental laboratory technology). The analysis consisted of…

  2. Information extraction from muon radiography data

    SciTech Connect

    Borozdin, K. N.; Asaki, T. J.; Chartrand, R.; Hengartner, N. W.; Hogan, G. E.; Morris, C. L.; Priedhorsky, W. C.; Schirato, R.C.; Schultz, L. J.; Sottile, M. J.; Vixie, K. R.; Wohlberg, B. E.; Blanpied, G.

    2004-01-01

    Scattering muon radiography was proposed recently as a technique of detection and 3-d imaging for dense high-Z objects. High-energy cosmic ray muons are deflected in matter in the process of multiple Coulomb scattering. By measuring the deflection angles we are able to reconstruct the configuration of high-Z material in the object. We discuss the methods for information extraction from muon radiography data. Tomographic methods widely used in medical images have been applied to a specific muon radiography information source. Alternative simple technique based on the counting of high-scattered muons in the voxels seems to be efficient in many simulated scenes. SVM-based classifiers and clustering algorithms may allow detection of compact high-Z object without full image reconstruction. The efficiency of muon radiography can be increased using additional informational sources, such as momentum estimation, stopping power measurement, and detection of muonic atom emission.

  3. Does cone-beam CT alter treatment plans? Comparison of preoperative implant planning using panoramic versus cone-beam CT images

    PubMed Central

    Guerrero, Maria Eugenia; Noriega, Jorge; Castro, Carmen

    2014-01-01

    Purpose The present study was performed to compare the planning of implant placement based on panoramic radiography (PAN) and cone-beam computed tomography (CBCT) images, and to study the impact of the image dataset on the treatment planning. Materials and Methods One hundred five partially edentulous patients (77 males, 28 females, mean age: 46 years, range: 26-67 years) seeking oral implant rehabilitation were referred for presurgical imaging. Imaging consisted of PAN and CBCT imaging. Four observers planned implant treatment based on the two-dimensional (2D) image datasets and at least one month later on the three-dimensional (3D) image dataset. Apart from presurgical diagnostic and dimensional measurement tasks, the observers needed to indicate the surgical confidence levels and assess the image quality in relation to the presurgical needs. Results All observers confirmed that both imaging modalities (PAN and CBCT) gave similar values when planning implant diameter. Also, the results showed no differences between both imaging modalities for the length of implants with an anterior location. However, significant differences were found in the length of implants with a posterior location. For implant dimensions, longer lengths of the implants were planned with PAN, as confirmed by two observers. CBCT provided images with improved scores for subjective image quality and surgical confidence levels. Conclusion Within the limitations of this study, there was a trend toward PAN-based preoperative planning of implant placement leading towards the use of longer implants within the posterior jaw bone. PMID:24944961

  4. Corrosion Inhibitors as Penetrant Dyes for Radiography

    NASA Technical Reports Server (NTRS)

    Novak, Howard L.; Hall, Phillip B.

    2003-01-01

    Liquid/vapor-phase corrosion inhibitors (LVCIs) have been found to be additionally useful as penetrant dyes for neutron radiography (and perhaps also x-radiography). Enhancement of radiographic contrasts by use of LVCIs can reveal cracks, corrosion, and other defects that may be undetectable by ultrasonic inspection, that are hidden from direct optical inspection, and/or that are difficult or impossible to detect in radiographs made without dyes.

  5. Does the quality of dental images depend on patient's age and sex ?- Explanations from the forensic sciences.

    PubMed

    Gelbrich, B; Gelbrich, G; Lessig, R

    2009-06-01

    The objective of this analysis was to investigate the dependency of image quality of dental panoramic radiographs on patient's age and sex, and to demonstrate that forensic science can explain these relationships. The image qualities of 100 dental panoramic radiographs obtained from 50 patients with two devices were assessed by ten independent observers of different specialisations. Image quality decreased with increasing age of the patients (P=0.003). One of the devices turned out to be superior to the other; however, this difference between the devices was present only in older patients but not in young ones (P=0.03). Image quality was higher in women than in men (P=0.01). The observed influences of age and sex are explained by results of forensic investigations concerning age-related changes of the dental pulp and sex differences of the skull geometry. Thus forensic science can elucidate effects relevant for everyday clinical practice. Studies on dental image quality must consider age and sex of the patients. PMID:22717952

  6. The prevalence of specific dental anomalies in a group of Saudi cleft lip and palate patients

    PubMed Central

    Al-Kharboush, Ghada H.; Al-Balkhi, Khalid M.; Al-Moammar, Khalid

    2015-01-01

    Objective The aims of this study were to investigate the prevalence and distribution of dental anomalies in a group of Saudi subjects with cleft lip and palate (CLP), to examine potential sex-based associations of these anomalies, and to compare dental anomalies in Saudi subjects with CLP with published data from other population groups. Design This retrospective study involved the examination of pre-treatment records obtained from three CLP centers in Riyadh, Saudi Arabia, in February and March 2010. The pre-treatment records of 184 subjects with cleft lip and palate were identified and included in this study. Pre-treatment maxillary occlusal radiographs of the cleft region, panoramic radiographs, and orthodontic study models of subjects with CLP were analyzed for dental anomalies. Results Orthopantomographs and occlusal radiographs may not be reliable for the accurate evaluation of root malformation anomalies. A total of 265 dental anomalies were observed in the 184 study subjects. Hypodontia was observed most commonly (66.8%), followed by microdontia (45.6%), intra-oral ectopic eruption (12.5%), supernumerary teeth (12.5%), intra-nasal ectopic eruption (3.2), and macrodontia (3.2%). No gender difference in the prevalence of these anomalies was observed. Conclusions Dental anomalies were common in Saudi subjects with CLP type. This will complicate the health care required for the CL/P subjects. This study was conducted to epidemiologically explore the prevalence of dental anomalies among Saudi Arabian subjects with CLP. PMID:26082573

  7. Dental education in Mexico.

    PubMed

    Masuoka, David; Komabayashi, Takashi; Reyes-Vela, Enrique

    2014-06-01

    The aim of this article is to provide information about dental education in Mexico, including its history, the dental school system, curriculum and dental licensure. In 1977, there were only 59 Mexican dental schools; however, there were 83 schools registered in the last official national count in 2007. Forty-one dental schools are public, and the other 42 are private. Every year the number of private dental schools increases. Admission to dental schools in Mexico requires a high school diploma. All classes are conducted in Spanish. To obtain licensure in Mexico, dental students must complete a 3 to 5-year program plus a year of community service. No formal nationwide standard clinical/didactic curriculum exists in Mexico. There are approximately 153,000 dentists in Mexico, a number that increases each year. The dentist-patient ratio is approximately 1:700. However, the high percentage of inactive licensed dentists in Mexico points to a serious problem. PMID:24984634

  8. Dental education in Malaysia.

    PubMed

    Komabayashi, Takashi; Razak, Abdul Aziz Abdul; Bird, William F

    2007-12-01

    There was only one dental school in Malaysia until 1997 but five new schools have been established since 1998. This review provides information about dental education in Malaysia including; the history of dental education, the current dental school system and curriculum, and dental licensure. There are four public and two private dental schools in Malaysia. High school graduates are required to take the nationwide matriculation entrance examination or the Higher School Certificate (HSC) to apply for a dental degree programme. A five-year dental programme leads to the BDS or the DDS degree. National or state examinations are not required to practise dentistry. Currently, there are approximately 2,500 dentists, with a ratio of 1 dentist for every 10,000 people. PMID:18265775

  9. American Dental Education Association

    MedlinePlus

    ... work hard to help your students fulfill their dreams, and play a crucial... Learn more Dental School ... Terms of Use | Website Feedback | Website Help ©2016 American Dental Education Association® (ADEA), 655 K Street, NW, ...

  10. Evaluating the Reliability of Three Different Dental Age Estimation Methods in Visakhapatnam Children

    PubMed Central

    Vabbalareddy, Raja Sekhar; V Vanga, Narasimha Rao

    2014-01-01

    ABSTRACT% Dental age is important for treatment planning in the specialities of pedodontics and orthodontics. Although, Demirjian's method was considered standard for dental age estimation, it may not be reliable for all population. Aim: The goal of the study was to evaluate the reliability of Demir-jian's, Haavikko's and Willems method of dental age estimation methods in Visakhapatnam (Andhra Pradesh, India) children. Study design: One hundred and two children of 6 to 14 years old who underwent panaromic digital radiography for routine diagnostic purposes were included. Dental age was calculated using Demirjian's, Haavikko's and Willems methods and compared with chronologic age for each patient. Results: Dental age showed a significant overestimation by Demirjian's method with a mean difference of 0.55 year and underestimation by Haavikko's and Willems methods with a mean difference of 1.95 and 0.20 year respectively when compared with chronologic age. The mean difference between dental age and chronologic age was not significant in Willems method which shows a close relation between dental and chronologic ages. Conclusion: The dental age estimation by Willems method is found to be more accurate than Demirjian's and Haavikko's methods in Visakhapatnam children. How to cite this article: Patnana AK, Vabbalareddy RS, Vanga NRV. Evaluating the Reliability of Three Different Dental Age Estimation Methods in Visakhapatnam Children. Int J Clin Pediatr Dent 2014;7(3):186-191. PMID:25709299

  11. Panoramic imaging mass-spectrometer for planetary studies

    NASA Astrophysics Data System (ADS)

    Vaisberg, O.; Berthelier, J.-J.; Torkar, K.; Leblanc, F.; Woch, J.; Avanov, L.; Skalski, A.; Delcourt, D.; Smirnov, V.; Koinash, G.

    Plasma diagnostics can provide extremely useful information for solar system studies. Neutral and ion sputtering from the surface leads to the formation of neutral and ion exospheres with compositions that reflect the surface composition modified by ionization and transport processes around the body. Measurements of ion composition and velocity distributions provide important information about surface composition and its recycling. Plasma measurements from low altitude spacecraft and landers on planetary bodies without atmospheres can be used to map the surface composition, while spectrometers onboard spacecraft orbiting planets with atmosphere are used for study of planetary losses, mass-exchange with the solar wind, and the long-term evolution of their environment. To perform reliable measurements of planetary plasmas a complete 3-dimensional velocity distributions of various ion species is necessary. In addition, if fast measurements of the major ion species are the main goal of plasma physics studies, precise measurements of the minor ion composition are often essential to unveil important properties of the atmosphere or the surface. Therefore ion mass spectrometers for solar system missions require both the capability of making fast measurements of the 3D-velocity distribution of ions and high mass resolution for detailed composition studies. We describe a novel type of miniature panoramic ion mass-spectrometer suitable for making such 3-dimensional measurements of ion components with high mass resolution. The feeding electron optics of our plasma analyzer (CAMERA) allows for fast measurements within an instantaneous 2π field of view, which has no gaps and can be accomplished on either stabilized or rotating spacecraft, or landers. It is followed by a time-of-flight mass-spectrometer that retains imaging capabilities of the feeding optics and provides mass-resolution M/?M in excess of 100. Our spectrometer also provides flexible control of the energy

  12. Hygiene implications associated with x-ray exposures to dental patients

    SciTech Connect

    McKlveen, J.W.

    1980-12-01

    An elastic mask worn by patients, then a skeleton encased in plastic, was instrumented with LiF thermoluminescent dosimeters to quantify radiation exposures delivered from full-face diagnostic dental x-rays. Locations of interest included skin surface, eyes, upper and lower teeth and thyroid. Exposures in the 100 mR range were common and a maximum of over 6000 mR was measured in the teeth region during a full-face examination with a periapical unit. In general, exposures received from periapical equipment were several times those obtained from panoramic devices.

  13. Bilateral dentigerous cysts that involve all four dental quadrants: a case report and literature review

    PubMed Central

    2016-01-01

    Dentigerous cysts are common odontogenic cysts that are associated with the crown of the tooth and typically develop from single lesions. Bilateral and multiple dentigerous cysts are very rare and occur in patients with syndromic conditions. This paper presents a case report of a 15-year-old male patient that experienced non-syndromic bilateral dentigerous cysts that simultaneously occurred in all four dental quadrants around the unerupted third molars. Clinicians should confirm the extent of cystic lesions using a panoramic view and computed tomography, and should keep the possibility of bilateral dentigerous cysts in mind as a potential diagnosis, even in a non-syndromic patient. PMID:27162755

  14. Comparison of antegonial index, mental index, panoramic mandibular index and mandibular cortical index values in the panoramic radiographs of normal males and male patients with osteoporosis

    PubMed Central

    Dagistan, S; Bilge, OM

    2010-01-01

    Objective The aim of the study was to compare the values of the antegonial index (AI), mental index (MI), panoramic mandibular index (PMI) and mandibular cortical index (MCI) in the panoramic radiographs of normal males and male patients with osteoporosis. Methods In panoramic radiographs obtained from 40 male individuals (20 normal and 20 with osteoporosis), the mean was calculated for MI, AI, PMI and MCI index values measured in the right and left mandibles. The MI, AI and PMI index values were evaluated using the paired t-test, and MCI values were analysed using the χ2 test. Results MI (P < 0.001), AI (P < 0.01) and PMI (P < 0.05) values were significantly smaller in the group with osteoporosis; however, MCI (P > 0.05) was not significantly different. Conclusion MI, PMI and AI values, as radiomorphometric indices, were found to be smaller among male patients with osteoporosis, compared with normal patients in this study. It is suggested that these indices, used as an ancillary method in the diagnosis of osteoporosis in women, could also be useful for male patients. Further studies, of larger groups are needed on this subject, including of the MCI, which in this study showed no significant difference. PMID:20587653

  15. Dental Laboratory Technology.

    ERIC Educational Resources Information Center

    Department of the Air Force, Washington, DC.

    The Air Force dental laboratory technology manual is designed as a basic training text as well as a reference source for dental laboratory technicians, a specialty occupation concerned with the design, fabrication, and repair of dental prostheses. Numerous instructive diagrams and photographs are included throughout the manual. The comprehensive…

  16. Perspectives from Dental Research.

    ERIC Educational Resources Information Center

    Baum, Bruce J.

    1996-01-01

    This paper responds to the Institute of Medicine's 1995 report concerning the present status and future needs of dental education in the United States. It examines whether real reform is occurring at the National Institute of Dental Research, within the academic dental community, and within the practicing profession. It concludes that very little…

  17. Dental Manpower Fact Book.

    ERIC Educational Resources Information Center

    Ake, James N.; Johnson, Donald W.

    Statistical data on many aspects of dental and allied dental personnel supply, distribution, characteristics, and education and on certain other aspects of dental services are presented and discussed. The data on dentist supply show the national trend in the supply of active dentists since 1950 and the concurrent changes in dentist-to-population…

  18. DENTAL SCHOOL PLANNING.

    ERIC Educational Resources Information Center

    GALAGAN, DONALD J.

    THIS DISCUSSION PRESENTS A COMPLETE PICTURE OF THE CURRENT STATE OF DENTAL EDUCATION WITH SUGGESTIONS FOR MEETING THE DEMANDS FOR DENTAL STAFF AND FACILITIES. THE AREAS INVESTIGATED ARE (1) OBJECTIVES IN DENTAL EDUCATION--COURSES, TEACHING MODES, INNOVATIONS IN CURRICULUM, COORDINATION OF BASIC AND CLINICAL INSTRUCTION, (2) FACILITY…

  19. The usefulness of dental and cervical maturation stages in New Zealand children for Disaster Victim Identification.

    PubMed

    Timmins, Kimberley; Liversidge, Helen; Farella, Mauro; Herbison, Peter; Kieser, Jules

    2012-06-01

    Age estimation of young victims of natural and un-natural disasters remains a crucial and challenging task during the process of Disaster Victim Identification (DVI). The purpose of this study was to compare dental maturity using the Demirjian and Cameriere methods and to explore the relationship between dental age and cervical vertebral maturity (CVM) using the Hassel and Farman method for a group of New Zealand children. The study used lateral cephalometric and panoramic radiographs of 200 orthodontic patients aged 7-17 years. Dental age was calculated from mandibular tooth formation stages using the Demirjian and Cameriere methods by calculating the ratio of tooth length to apex width for these teeth. CVM was assessed using stages from Hassel and Farman. Reliability of maturity from reassessment of 20 radiographs showed good agreement for the three methods. Chronological and dental ages were compared using a mixed model. Descriptive statistics of dental ages by CVM stage were calculated. The results show that both dental methods were similar in assessing maturity. A disadvantage of using the Cameriere method was that all seven teeth reached maturity at 13.69 and 14.06 years in females and males respectively, compared to age 16 using the Dermijian method. Females reached CVM stages at earlier chronological and dental ages than males. Mean chronological age for CVM stages 2-5 is about 1 year earlier in females than males. The Demirjian and Cameriere methods of dental maturity and CVM are reliable and useful in assessing dental and skeletal maturity. Ideally in a DVI situation, both the methods of Demirjian and Cameriere, together with CVM, should be employed in the ageing of individuals suspected of being between 7 and 16 years. PMID:21667171

  20. Weaker dental enamel explains dental decay.

    PubMed

    Vieira, Alexandre R; Gibson, Carolyn W; Deeley, Kathleen; Xue, Hui; Li, Yong

    2015-01-01

    Dental caries continues to be the most prevalent bacteria-mediated non-contagious disease of humankind. Dental professionals assert the disease can be explained by poor oral hygiene and a diet rich in sugars but this does not account for caries free individuals exposed to the same risk factors. In order to test the hypothesis that amount of amelogenin during enamel development can influence caries susceptibility, we generated multiple strains of mice with varying levels of available amelogenin during dental development. Mechanical tests showed that dental enamel developed with less amelogenin is "weaker" while the dental enamel of animals over-expressing amelogenin appears to be more resistant to acid dissolution. PMID:25885796

  1. DIAGNOSTIC AGREEMENT BETWEEN PANORAMIC RADIOGRAPHS AND COLOR DOPPLER IMAGES OF CAROTID ATHEROMA

    PubMed Central

    Romano-Sousa, Claudia Maria; Krejci, Laís; Medeiros, Flavilene Marchioro Martins; Graciosa, Ricardo Gomes; Martins, Maria Fernanda Fonseca; Guedes, Vanessa Novaes; Fenyo-Pereira, Marlene

    2009-01-01

    The aim of this study was to investigate the agreement between diagnoses of calcified atheroma seen on panoramic radiographs and color Doppler images. Our interest stems from the fact that panoramic images can show the presence of atheroma regardless of the level of obstruction detected by color Doppler images. Panoramic and color Doppler images of 16 patients obtained from the archives of the Health Department of the city of Valença, RJ, Brazil, were analyzed in this study. Both sides of each patient were observed on the images, with a total of 32 analyzed cervical regions. The level of agreement between diagnoses was analyzed using the Kappa statistics. There was a high level of agreement, with a Kappa value of 0.78. In conclusion, panoramic radiographs can help detecting calcifications in the cervical region of patients susceptible to vascular diseases predisposing to myocardial infarction and cerebrovascular accidents. If properly trained and informed, dentists can refer their patients to a physician for a cardiovascular evaluation in order to receive proper and timely medical treatment. PMID:19148405

  2. Topographic Data Derived from Scans of the Original Apollo Panoramic Flight Film

    NASA Astrophysics Data System (ADS)

    Rosiek, M. R.; Lawrence, S. J.; Robinson, M. S.; Close, W.; Grunsfeld, J.; Ingram, R.; Jefferson, L.; Locke, S.; Mitchell, R.; Scarsella, T.; White, M.; Archinal, B. A.; Hare, T.; Redding, B. L.; Galuszka, D. M.; Hopkins, M.

    2010-03-01

    JSC and ASU are creating a digital archive of the Apollo flight films. Panoramic stereo models are useful for topographic mapping. Image resolution varies from 1-2 m/pixel. Expected vertical accuracy of the topographic data is 0.5-1.5 m.

  3. AMOLED image source for use in integrated panoramic night vision goggle (IPNVG)

    NASA Astrophysics Data System (ADS)

    Ross, Jeff A.; Parisi, Vince

    2004-09-01

    The objective of this paper is to present an overview of the active matrix organic light emitting diode (OLED) microdisplay used in the integrated panoramic night vision goggle (IPNVG). These devices will be used to insert independent and overlaid video imagery into the IPNVG. Interface and operational details of the microdisplay relative to the IPNVG implementation in military aircraft will be discussed.

  4. Evaluation of Radiomorphometric Indices in Panoramic Radiograph – A Screening Tool

    PubMed Central

    Bajoria, Atul Anand; ML, Asha; Kamath, Geetha; Babshet, Medha; Patil, Preeti; Sukhija, Piyush

    2015-01-01

    Background : Mandibular cortical indices, like the mandibular cortical index (MCI), panoramic mandibular index (PMI), mental index (MI), antegonial index (AI) and gonial index (GI) have been developed to assess and quantify the quality of mandibular bone mass. Aim and Objectives : The aim of this pilot study was to measure the radiomorphometric indices in a digital panoramic radiograph and find the inter-relationship of the indices with age and sex of the patients. Materials and Method : A total of 23 randomly selected patients were included in the study. Panoramic radiograph of each patient was taken and radiomorphometric indices were determined. Results : There was 69.57% agreement between MI and PMI which was significant. Similarly 78.26% agreement was seen between AI and MI which was significant. In contrast 30.43%, 52.17% and 56.52% agreement was observed while comparing GI with PMI, MI and AI respectively. Conclusion : MCI, PMI, AI and MI can be effectively measured on a panoramic radiograph, hence could be used as a screening tool for determining osteoporosis. All indices have a negative correlation with age and a significant difference between the younger and older age groups. All indices were significantly lower in females when compared to males of the same age group. PMID:26464600

  5. Panoramic imaging is not suitable for quantitative evaluation, classification, and follow up in unilateral condylar hyperplasia.

    PubMed

    Nolte, J W; Karssemakers, L H E; Grootendorst, D C; Tuinzing, D B; Becking, A G

    2015-05-01

    Patients with suspected unilateral condylar hyperplasia are often screened radiologically with a panoramic radiograph, but this is not sufficient for routine diagnosis and follow up. We have therefore made a quantitative analysis and evaluation of panoramic radiographs in a large group of patients with the condition. During the period 1994-2011, 132 patients with 113 panoramic radiographs were analysed using a validated method. There was good reproducibility between observers, but the condylar neck and head were the regions reported with least reliability. Although in most patients asymmetry of the condylar head, neck, and ramus was confirmed, the kappa coefficient as an indicator of agreement between two observers was poor (-0.040 to 0.504). Hardly any difference between sides was measured at the gonion angle, and the body appeared to be higher on the affected side in 80% of patients. Panoramic radiographs might be suitable for screening, but are not suitable for the quantitative evaluation, classification, and follow up of patients with unilateral condylar hyperplasia. PMID:25798757

  6. Panoramic optical annular staring inspection system for evaluating the inner surface of a pipe

    NASA Astrophysics Data System (ADS)

    Zhao, Liefeng; Feng, Huajun; Bai, Jian; Jin, Hao

    2008-01-01

    There should be flaws and defects on the inner surface during the producing period of a pipe, as well as contaminations and corrosions during the using period of it. A corresponding panoramic optical annular staring inspection system has been developed. It requires no rotating mechanism to exam the whole circumference of a cross section of the inner pipe surface at once, which results high speed inspection. There are two main subsystems in this inspection system, the panoramic optical annular staring imaging subsystem and driving robot subsystem. The Flat Cylinder Perspective (FCP) is the principle to image a panoramic annular view to a flat imagery, i.e. a cylinder of vision imaged is flat. Our imaging subsystem includes a panoramic annular lens (PAL), which is critical and used to implement the FCP, a series of image rotation lenses, a charge-coupled device (CCD) camera, and an illuminating light-emitting diode (LED) ring. The CCD camera sending the signal to a personal computer (PC) via VGA signal results a real time inspection. The driving robot subsystem is a fine designed complicated mechanism including a subassembly of stepper motor. It can drive the inspection system forward and backward continuously in the pipe along the axial direction. The experimental system reported in this paper has the following specifications: average detection resolution of 0.5 mm at the circumference direction and 1.0 mm at the axial direction of a pipe, and inspection speed of 15 mm/s.

  7. OROFACIAL FINDINGS AND DENTAL MANAGEMENT OF WILLIAMS SYNDROME.

    PubMed

    Cogulu, D; Hazan, F; Dindaroglu, F Cagirir

    2015-01-01

    Williams Syndrome is a microdeletion syndrome characterized by a number of developmental and physical abnormalities. The aim of the present study was to evaluate the oral abnormalities and dental management of patients with Williams Syndrome. Fifteen patients with Williams Syndrome aged between 3-20 years old were evaluated in this study. Oro-facial findings, dental plaque index and DMFT/dmft scores were recorded in each patient. Panoramic radiographs and extraoral, intraoral photographs were taken from all patients. According to the results of this study, the mean DMFT and dmft scores were 0.39 ± 0.12 and 1.81 ± 0.39, respectively. The most common oro-facial findings were detected as high palate (87%), diastema (60%), failure to thrive (60%), feeding difficulties (60%), vomiting (47%), macroglossi (47%), microdontia (40%) and frenulum hyperplasia (40%). All decayed teeth were restored with compomer and composite restorations. In conclusion, dentists play a significant role for improving the quality of life of the patients with Williams Syndrome to minimize or prevent dental abnormalities. PMID:26852515

  8. Applications of Panoramic Images: from 720° Panorama to Interior 3d Models of Augmented Reality

    NASA Astrophysics Data System (ADS)

    Lee, I.-C.; Tsai, F.

    2015-05-01

    A series of panoramic images are usually used to generate a 720° panorama image. Although panoramic images are typically used for establishing tour guiding systems, in this research, we demonstrate the potential of using panoramic images acquired from multiple sites to create not only 720° panorama, but also three-dimensional (3D) point clouds and 3D indoor models. Since 3D modeling is one of the goals of this research, the location of the panoramic sites needed to be carefully planned in order to maintain a robust result for close-range photogrammetry. After the images are acquired, panoramic images are processed into 720° panoramas, and these panoramas which can be used directly as panorama guiding systems or other applications. In addition to these straightforward applications, interior orientation parameters can also be estimated while generating 720° panorama. These parameters are focal length, principle point, and lens radial distortion. The panoramic images can then be processed with closerange photogrammetry procedures to extract the exterior orientation parameters and generate 3D point clouds. In this research, VisaulSFM, a structure from motion software is used to estimate the exterior orientation, and CMVS toolkit is used to generate 3D point clouds. Next, the 3D point clouds are used as references to create building interior models. In this research, Trimble Sketchup was used to build the model, and the 3D point cloud was added to the determining of locations of building objects using plane finding procedure. In the texturing process, the panorama images are used as the data source for creating model textures. This 3D indoor model was used as an Augmented Reality model replacing a guide map or a floor plan commonly used in an on-line touring guide system. The 3D indoor model generating procedure has been utilized in two research projects: a cultural heritage site at Kinmen, and Taipei Main Station pedestrian zone guidance and navigation system. The

  9. Mobile real time radiography system

    SciTech Connect

    Vigil, J.; Taggart, D.; Betts, S.

    1997-11-01

    A 450-keV Mobile Real Time Radiography (RTR) System was delivered to Los Alamos National Laboratory (LANL) in January 1996. It was purchased to inspect containers of radioactive waste produced at (LANL). Since its delivery it has been used to radiograph more than 600 drums of radioactive waste at various LANL sites. It has the capability of inspecting waste containers of various sizes from <1-gal. buckets up to standard waste boxes (SWB, dimensions 54.5 in. x 71 in. x 37 in.). It has three independent x-ray acquisition formats. The primary system used is a 12- in. image intensifier, the second is a 36-in. linear diode array (LDA) and the last is an open system. It is fully self contained with on board generator, HVAC, and a fire suppression system. It is on a 53-ft long x 8-ft. wide x 14-ft. high trailer that can be moved over any highway requiring only an easily obtainable overweight permit because it weights {approximately}38 tons. It was built to conform to industry standards for a cabinet system which does not require an exclusion zone. The fact that this unit is mobile has allowed us to operate where the waste is stored, rather than having to move the waste to a fixed facility.

  10. Modified Bootstrap Sensitometry In Radiography

    NASA Astrophysics Data System (ADS)

    Bednarek, Daniel R.; Rudin, Stephen

    1981-04-01

    A new modified bootstrap approach to sensitometry is presented which provides H and D curves that show almost exact agreement with those obtained using conventional methods. Two bootstrap techniques are described; both involve a combination of inverse-square and stepped-wedge modulation of the radiation field and provide intensity-scale sensitometric curves as appropriate for medical radiography. H and D curves obtained with these modified techniques are compared with those obtained for screen-film combinations using inverse-square sensitometry as well as with those obtained for direct x-ray film using time-scale sensitometry. The stepped wedge of the Wisconsin X-Ray Test Cassette was used in the bootstrap approach since it provides sufficient exposure latitude to encompass the useful density range of medical x-ray film. This approach makes radiographic sensitometry quick and convenient, allowing accurate characteristic curves to be obtained for any screen-film cassette using standard diagnostic x-ray equipment.

  11. Thorium-uranium fission radiography

    NASA Technical Reports Server (NTRS)

    Haines, E. L.; Weiss, J. R.; Burnett, D. S.; Woolum, D. S.

    1976-01-01

    Results are described for studies designed to develop routine methods for in-situ measurement of the abundance of Th and U on a microscale in heterogeneous samples, especially rocks, using the secondary high-energy neutron flux developed when the 650 MeV proton beam of an accelerator is stopped in a 42 x 42 cm diam Cu cylinder. Irradiations were performed at three different locations in a rabbit tube in the beam stop area, and thick metal foils of Bi, Th, and natural U as well as polished silicate glasses of known U and Th contents were used as targets and were placed in contact with mica which served as a fission track detector. In many cases both bare and Cd-covered detectors were exposed. The exposed mica samples were etched in 48% HF and the fission tracks counted by conventional transmitted light microscopy. Relative fission cross sections are examined, along with absolute Th track production rates, interaction tracks, and a comparison of measured and calculated fission rates. The practicality of fast neutron radiography revealed by experiments to data is discussed primarily for Th/U measurements, and mixtures of other fissionable nuclei are briefly considered.

  12. Correlating skeletal and dental developmental stages using radiographic parameters.

    PubMed

    Cericato, Graziela Oro; Franco, Ademir; Bittencourt, Marcos Alan Vieira; Nunes, Marco Antonio Prado; Paranhos, Luiz Renato

    2016-08-01

    The demand for age estimation of living and deceased children considerably increased in the last years. It was mainly justified by the growing globalization trend and the enlarged amount of violent crimes involving young victims. The present research aims to correlate skeletal and dental developmental stages using radiographic parameters. Lateral cephalometric (n = 576) and panoramic (n = 576) radiographs taken in the same moment were used to asses skeletal and dental development according to the methods of Hassel and Farman (1995) and Bacetti et al. (2002), and Demirjian et al. (1973), respectively. Likelihood-ratio test was used to verify the positive prediction in correlations between developmental stages. Spearman's correlation coefficient was calculated between skeletal and dental developmental stages, as well between estimated and chronological ages. Higher prediction in correlation for the skeletal starting stage (stage 1) with stage E in mandibular canines, and with stage D in mandibular premolars and second molars was detected. Higher staging correlations were observed considering the mandibular left second premolar (0.652, p < 0.001 for the technique of Bacetti et al.; and 0.646, p < 0.001 for the technique of Hassel and Farman). Despite the correlations between skeletal and dental developmental stages, the results must be carefully interpreted once it reached moderate values (<0.652). Further researches must test different classifications of skeletal and dental development, in order to verify the possibility of replacing one technique for another with stronger correlation. PMID:27219112

  13. Time of flight fast neutron radiography

    NASA Astrophysics Data System (ADS)

    Loveman, R.; Bendahan, J.; Gozani, T.; Stevenson, J.

    1995-05-01

    Neutron radiography with fast or thermal neutrons is a standard technique for non-destructive testing (NDT). Here we report results for fast neutron radiography both as an adjunct to pulsed fast neutron analysis (PFNA) and as a stand-alone method for NDT. PFNA is a new technique for utilizing a collimated pulsed neutron beam to interrogate items and determine their elemental composition. By determining the time of flight for gamma-rays produced by (n,n' gamma X) reactions, a three dimensional image can be produced. Neutron radiography data taken with the same beam provides an important constraint for image reconstruction, and in particular is important in inferring the amount of hydrogen within the interrogated item. As a stand-alone device, the radiography measurement can be used to image items as large as cargo containers as long as their density is not too high. The use of a pulsed beam gives the further advantage of a time of flight measurement on the transmitted neutrons. By gating the radiography signal on the time of flight appropriate to the energy of the primary neutrons, most build-up from scattered neutrons can be eliminated. The pulsed beam also greatly improves the signal to background and extends the range of the neutron radiography. Simulation results will be presented which display the advantage of this constraint in particular for statistically limited data. Experimental results will be presented which show some of the limitations likely in a PFNA system utilizing neutron radiography data. Experimental and simulation results will demonstrate possible uses for this type of radiographic data in identifying contraband substances such as drugs.

  14. DENTAL MATURITY AS AN INDICATOR OF CHRONOLOGICAL AGE: RADIOGRAPHIC ASSESSMENT OF DENTAL AGE IN A BRAZILIAN POPULATION

    PubMed Central

    Kurita, Lucio Mitsuo; Menezes, Alynne Vieira; Casanova, Marcia Spinelli; Haiter-Neto, Francisco

    2007-01-01

    Objective: The purpose of this investigation was to evaluate the applicability of the methods proposed by Nolla and by Nicodemo and colleagues for assessing dental age and its correlation to chronological age. Methods: Panoramic radiographs of 360 patients from the city of Fortaleza (CE, Brazil) aged 7-15 years were used to assess the associations between dental and chronological age. Data were submitted to statistical analysis using the BioEstat 2.0 (2000) software. Student-Neuman-Keuls test was performed and Pearson's correlation coefficients were calculated at 5% significance level. Results: When the Nolla method was applied, the mean difference between true and estimated age for males and females was underestimated. The use of the method proposed by Nicodemo and colleagues also resulted in underestimation, although it was more evident in male subjects. The correlation coefficients between chronological age and estimated dental age were high, with mean values ranging between 0.87 and 0.91 for males and between 0.84 and 0.93 for females. Conclusion: Although both methods proved to be reliable in estimating age, the use of correction factors is recommended. PMID:19089110

  15. Frequency of Tonsilloliths in Panoramic Views of a Selected Population in Southern Iran

    PubMed Central

    Ghabanchi, Janan; Haghnegahdar, Abdolaziz; Khojastehpour, Leila; Ebrahimi, Ali

    2015-01-01

    Statement of the Problem Tonsilloliths are relatively common clusters of dystrophic calcified material that form in the tonsillar crypts, mostly the palatine tonsils. Although they may be asymptomatic, some cause halitosis, cough, dysphagia, and foreign body sensation, as well as otalgia. Since tonsilloliths can be detected on panoramic views as radiopaque lesions, and misdiagnosis may lead to wasting time and cost, dentist should be familiar with radiographic characteristics of this type of calcification. Purpose This study was conducted to determine the prevalence and the pattern of distribution of tonsilloliths on panoramic radiographs. Materials and Method This cross-sectional study was based on 2000 panoramic radiographs from 1030 female and 970 male aged 6-75 years old evaluated for the presence and pattern of tonsillolithiasis, between 2011 and 2013 in Shiraz, Iran. Chi–square test and odds ratio were used to evaluate the relationship between tonsillolithiasis and gender. p< 0.05 was considered as statistically significant. Results Out of the 2000 individuals, 101 cases (5.05%) had tonsilloliths on panoramic radiographs out of which 61 were male (60.4%) and 40 were female (39.6%), with age range of 18 to 65. Forty patients (39.6%) had both left and right sides involved, 25 of tonsilloliths (24.75%) were located on the right and 36 on the left side (35.65%). Men were more likely to develop tonsilloliths (p= 0.014). Conclusion Tonsilloliths are not very common finding and can be detected on nearly 5.05% of panoramic radiographs. Most of the cases are unilateral with a diameter less than 2mm. PMID:26046101

  16. Description and Documentation of the Dental School Dental Delivery System.

    ERIC Educational Resources Information Center

    Chase, Rosen and Wallace, Inc., Alexandria, VA.

    A study was undertaken to describe and document the dental school dental delivery system using an integrated systems approach. In late 1976 and early 1977, a team of systems analysts and dental consultants visited three dental schools to observe the delivery of dental services and patient flow and to interview administrative staff and faculty.…

  17. Muon radiography for exploration of Mars geology

    NASA Astrophysics Data System (ADS)

    Kedar, S.; Tanaka, H. K. M.; Naudet, C. J.; Jones, C. E.; Plaut, J. P.; Webb, F. H.

    2013-06-01

    Muon radiography is a technique that uses naturally occurring showers of muons (penetrating particles generated by cosmic rays) to image the interior of large-scale geological structures in much the same way as standard X-ray radiography is used to image the interior of smaller objects. Recent developments and application of the technique to terrestrial volcanoes have demonstrated that a low-power, passive muon detector can peer deep into geological structures up to several kilometers in size, and provide crisp density profile images of their interior at ten meter scale resolution. Preliminary estimates of muon production on Mars indicate that the near horizontal Martian muon flux, which could be used for muon radiography, is as strong or stronger than that on Earth, making the technique suitable for exploration of numerous high priority geological targets on Mars. The high spatial resolution of muon radiography also makes the technique particularly suited for the discovery and delineation of Martian caverns, the most likely planetary environment for biological activity. As a passive imaging technique, muon radiography uses the perpetually present background cosmic ray radiation as the energy source for probing the interior of structures from the surface of the planet. The passive nature of the measurements provides an opportunity for a low power and low data rate instrument for planetary exploration that could operate as a scientifically valuable primary or secondary instrument in a variety of settings, with minimal impact on the mission's other instruments and operation.

  18. Weakly ionized cerium plasma radiography

    NASA Astrophysics Data System (ADS)

    Sato, Eiichi; Hayasi, Yasuomi; Germer, Rudolf; Koorikawa, Yoshitake; Murakami, Kazunori; Tanaka, Etsuro; Mori, Hidezo; Kawai, Toshiaki; Ichimaru, Toshio; Obata, Fumiko; Takahashi, Kiyomi; Sato, Sigehiro; Takayama, Kazuyoshi; Ido, Hideaki

    2004-02-01

    In the plasma flash x-ray generator, high-voltage main condenser of about 200 nF is charged up to 55 kV by a power supply, and electric charges in the condenser are discharged to an x-ray tube after triggering the cathode electrode. The flash x-rays are then produced. The x-ray tube is of a demountable triode that is connected to a turbo molecular pump with a pressure of approximately 1 mPa. As electron flows from the cathode electrode are roughly converged to a rod cerium target of 3.0 mm in diameter by electric field in the x-ray tube, the weakly ionized linear plasma, which consists of cerium ions and electrons, forms by target evaporating. At a charging voltage of 55 kV, the maximum tube voltage was almost equal to the charging voltage of the main condenser, and the peak current was about 20 kA. When the charging voltage was increased, weakly ionized cerium plasma formed, and the K-series characteristic x-ray intensities increased. The x-ray pulse widths were about 500 ns, and the time-integrated x-ray intensity had a value of about 40 μC/kg at 1.0 m from x-ray source with a charging voltage of 55 kV. In the angiography, we employed a film-less computed radiography (CR) system and iodine-based microspheres. Because K-series characteristic x-rays are absorbed easily by the microspheres, high-contrast angiography has been performed.

  19. Evaluation of surface radiation dose to the thyroid gland and the gonads during routine full-mouth intraoral periapical and maxillary occlusal radiography

    PubMed Central

    Sheikh, Soheyl; Bhoweer, Anil Kumar; Arya, Smriti; Arora, Gagandeep

    2010-01-01

    Aim: The quantitative aspects of radiation doses to critical organs can help the dental professionals to take the necessary radiation protective measures as deemed necessary and can help the general public to allay radiation exposure fear in dental radiography, if any. Our study determines the surface radiation dose to thyroid and gonads in full-mouth intraoral periapical (IOPA) and maxillary occlusal radiography. Materials and Methods: A total number of 120 subjects participated in the study. The surface radiation dose was estimated to the thyroid gland and the gonads in full-mouth IOPA radiography using 10 IOPA (E speed films) and in maxillary occlusal radiography. The measurements were calculated using a digital pocket dosimeter (PD-4507). Results: The average dose at the thyroid gland level during full-mouth intraoral and maxillary occlusal radiography was estimated to be 10.93 mRads (1.093 × 10-2 mGy) and 0.4 mRads (4.0 × 10-2 mGy), respectively. The average surface radiation dose at the gonadal region during a full mouth intraoral and maxillary occlusal radiography was estimated to be 1.5 mRads (1.5 × 10-2 mGy) and 0.15 mRads (1.5 × 10-3 mGy), respectively. Conclusion: Our results suggest that although the radiation exposure doses to critical organs namely thyroid and gonads is within the safe limits still precautionary measures for these organs are advocated. PMID:22114389

  20. Neutron radiography at the NRAD facility

    SciTech Connect

    McClellan, G.C.; Richards, W.J.

    1984-01-01

    The NRAD facility uses a 150 kW TRIGA reactor as a source of neutrons and is integrated with a hot cell such that highly radioactive specimens can be radiographed without removing them from the hot cell environment. A second beam tube is located in a separate shielded addition to HFEF and permits neutron radiography of irradiated or unirradiated specimens without subjecting them to the alpha-contaminated hot cell environment. Both beams are optimized for neutron radiography of highly radioactive nuclear fuels. Techniques for using these facilities are described. Advantages include: the ability to perform thermal and epithermal neutron radiography on specimens either inside or outside the hot cell, lack of competition for the use of the reactor, versatility of facility design, and the addition of neutron tomography. (LEW)

  1. Diagnostic Imaging of Dental Disease in Pet Rabbits and Rodents.

    PubMed

    Capello, Vittorio

    2016-09-01

    Diagnostic imaging techniques are of paramount importance for dentistry and oral disorders of rabbits, rodents, and other exotic companion mammals. Aside from standard radiography, stomatoscopy is a complementary tool allowing a thorough and detailed inspection of the oral cavity. Computed tomography (CT) generates multiple 2-dimensional views and 3-dimensional reconstructions providing superior diagnostic accuracy also useful for prognosis and treatment of advanced dental disease and its related complications. MRI is a diagnostic imaging technique additional to CT used primarily to enhance soft tissues, including complex odontogenic abscesses. PMID:27497205

  2. Employment of Dental Hygienists as Dental Educators.

    ERIC Educational Resources Information Center

    Fong, Cynthia; Odrich, Johanna

    1987-01-01

    A study of the use of dental hygienists to teach periodontics, preventive dentistry, community dentistry, and public health courses looked at employment patterns and practices and the qualifications of the teachers. (MSE)

  3. Meeting Dental Health Needs Through Dental Education

    ERIC Educational Resources Information Center

    Morris, Alvin L.

    1972-01-01

    Dental health needs of the country cannot be met through education of more dentists. Rather, we must educate auxiliaries to perform many of the intraoral procedures now regarded the sole responsibility of dentists. (SB)

  4. Digital radiography. A comparison with modern conventional imaging

    PubMed Central

    Bansal, G J

    2006-01-01

    The development of computed radiography over the past two decades has transformed radiological imaging. The radiology departments in the 21st century will look very different from those in the preceding period. In this review, the development of digital radiography is presented with a description of its various forms and a comparison with screen film radiography. PMID:16822918

  5. Proton Radiography: Its uses and Resolution Scaling

    SciTech Connect

    Mariam, Fesseha G.

    2012-08-09

    Los Alamos National Laboratory has used high energy protons as a probe in flash radiography for over a decade. In this time the proton radiography project has used 800 MeV protons, provided by the LANSCE accelerator facility at LANL, to diagnose over five-hundred dynamic experiments in support of stockpile stewardship programs as well as basic materials science. Through this effort significant experience has been gained in using charged particles as direct radiographic probes to diagnose transient systems. The results of this experience will be discussed through the presentation of data from experiments recently performed at the LANL pRad.

  6. New developments in proton radiography at LANSCE

    NASA Astrophysics Data System (ADS)

    Morris, Christopher; Proton Radiography Team

    2014-09-01

    In a new application of nuclear physics, a facility for using proton for flash radiography has been developed at the Los Alamos Neutron Science Center (LANSCE). Protons have proven far superior to high energy x-rays for flash radiography. Although this facility is primarily used for studying very fast phenomena such as high explosive driven experiments, it is finding increasing application to other fields, such as tomography of static objects, phase changes in materials, and the dynamics of chemical reactions. The advantages of protons will be discussed and data from some of the recent experiments will be presented.

  7. Lithium batteries: Application of neutron radiography

    NASA Astrophysics Data System (ADS)

    Kamata, Masahiro; Esaka, Takao; Fujine, Shigenori; Yoneda, Kenji; Kanda, Keiji

    Several kinds of primary and secondary commercial lithium batteries, such as CR1/3 · 1H (Fujitsu), CR1220 and BR435 (Panasonic), ML1220 (Sanyo Excel) were investigated using neutron radiography; the variation of the lithium distribution inside these batteries upon discharging (and charging) were clarified by analyzing their visualized images. It was demonstrated that neutron radiography is a potential and useful method, especially in evaluating the reversibility of rechargeable batteries, which have been used under different discharging/charging conditions.

  8. Quantitative studies on inner interfaces in conical metal joints using hard x-ray inline phase contrast radiography

    NASA Astrophysics Data System (ADS)

    Zabler, S.; Rack, T.; Rack, A.; Nelson, K.

    2010-10-01

    Quantitative investigation of micrometer and submicrometer gaps between joining metal surfaces is applied to conical plug-socket connections in dental titanium implants. Microgaps of widths well beyond the resolving power of industrial x-ray systems are imaged by synchrotron phase contrast radiography. Furthermore, by using an analytical model for the relatively simple sample geometry and applying it to numerical forward simulations of the optical Fresnel propagation, we show that quantitative measurements of the microgap width down to 0.1 μm are possible. Image data recorded at the BAMline (BESSY-II light source, Germany) are presented, with the resolving power of the imaging system being 4 μm in absorption mode and ˜14 μm in phase contrast mode (z2=0.74 m). Thus, phase contrast radiography, combined with numerical forward simulations, is capable of measuring the widths of gaps that are two orders of magnitude thinner than the conventional detection limit.

  9. Dental anomalies inside the cleft region in individuals with nonsyndromic cleft lip with or without cleft palate

    PubMed Central

    Sá, Jamile; Araújo, Luana; Guimarães, Laís; Maranhão, Samário; Lopes, Gabriela; Medrado, Alena; Coletta, Ricardo

    2016-01-01

    Background Individuals with non syndromic cleft lip with or without cleft palate (NSCL±P) present high frequency of dental anomalies, which may represent complicating factors for dental treatment. The aim of this study was to investigate the prevalence of dental anomalies inside cleft area in a group of Brazilians with NSCL±P. Material and Methods Retrospective analysis of 178 panoramic radiographs of patients aged from 12 to 45 years old and without history of tooth extraction or orthodontic treatment was performed. Association between cleft type and the prevalence of dental anomalies was assessed by chi-square test with a significance level set at p≤ 0.05. Results Dental anomalies were found in 88.2% (n=157) of the patients. Tooth agenesis (47.1%), giroversion (20%) and microdontia (15.5%) were the most common anomalies. Individuals with unilateral complete cleft lip and palate (CLP, p<0.0001), bilateral complete CLP (p=0.0002) and bilateral incomplete CLP (p< 0.0001) were more affected by tooth agenesis than individuals with other cleft types. The maxillary lateral incisors were the most affected teeth (p<0.0001). Conclusions The present study revealed a high frequency of dental anomalies inside cleft region in NSCL±P patients, and further demonstrated that patients with unilateral complete CLP and bilateral incomplete CLP were frequently more affected by dental anomalies. Moreover, our results demonstrate that dental anomalies should be considered during dental treatment planning of individuals affected by NSCL±P. Key words:Nonsyndromic cleft lip with or without palate, dental anomaly, tooth agenesis, microdontia. PMID:26615505

  10. HUBBLE'S PANORAMIC PORTRAIT OF A VAST STAR-FORMING REGION

    NASA Technical Reports Server (NTRS)

    2002-01-01

    NASA's Hubble Space Telescope has snapped a panoramic portrait of a vast, sculpted landscape of gas and dust where thousands of stars are being born. This fertile star-forming region, called the 30 Doradus Nebula, has a sparkling stellar centerpiece: the most spectacular cluster of massive stars in our cosmic neighborhood of about 25 galaxies. The mosaic picture shows that ultraviolet radiation and high-speed material unleashed by the stars in the cluster, called R136 [the large blue blob left of center], are weaving a tapestry of creation and destruction, triggering the collapse of looming gas and dust clouds and forming pillar-like structures that are incubators for nascent stars. The photo offers an unprecedented, detailed view of the entire inner region of 30 Doradus, measuring 200 light-years wide by 150 light-years high. The nebula resides in the Large Magellanic Cloud (a satellite galaxy of the Milky Way), 170,000 light-years from Earth. Nebulas like 30 Doradus are the 'signposts' of recent star birth. High-energy ultraviolet radiation from the young, hot, massive stars in R136 causes the surrounding gaseous material to glow. Previous Hubble telescope observations showed that R136 contains several dozen of the most massive stars known, each about 100 times the mass of the Sun and about 10 times as hot. These stellar behemoths all formed at the same time about 2 million years ago. The stars in R136 are producing intense 'stellar winds' (streams of material traveling at several million miles an hour), which are wreaking havoc on the gas and dust in the surrounding neighborhood. The winds are pushing the gas away from the cluster and compressing the inner regions of the surrounding gas and dust clouds [the pinkish material]. The intense pressure is triggering the collapse of parts of the clouds, producing a new generation of star formation around the central cluster. The new stellar nursery is about 30 to 50 light-years from R136. Most of the stars in the

  11. Development of the Permanent Dentition and Validity of Demirjian and Goldstein Method for Dental Age Estimation in Sample of Saudi Arabian Children (Qassim Region)

    PubMed Central

    Nour El Deen, Ragia E. H.; Alduaiji, Hifaa M.; Alajlan, Ghadir M.; Aljabr, Abdalla A.

    2016-01-01

    Objectives To determine dental maturity (dental age) in cross-sectional sample of Saudi Arabian children by applying the standards established by Demirjian and Golstein and to examine the applicability of these standards in determination of dental maturity among Saudi Arabian children (Qassim region). Materials & Methods Dental maturity was assessed from panoramic radiographs of 400 Saudi Arabian children, 222 boys, and 198 girls ranging in age from 4 to 14 years by using these standards. The difference between the dental and chronological age in different age groups in both sexes was statistically compared using ANOVA testat 0.05 level of significance. Results The Saudi Arabian children were generally somewhat advanced in dental maturity compared with the French Canadian reference sample with an overall mean difference between the dental and chronological age of 0.279 years in boys and 0.385 years in girls. Conclusion The applied standards appear to be adequate for studying dental age in groups of children among Saudi Arabian population. PMID:27004054

  12. Electronic intraoral dental x-ray imaging system employing a direct-sensing CCD array

    NASA Astrophysics Data System (ADS)

    Cox, John D.; Langford, D. S.; Williams, Donald W.

    1993-12-01

    A commercial prototype intraoral radiography system has been developed that can provide digital x-ray images for diagnosis. The system consists of an intraoral detector head, an intermediate drive electronics package, a main drive electronics package, and a PC-based digital image management system. The system has the potential to replace the use of dental film in intraoral radiographic examinations. High-resolution images are acquired, then displayed on a CRT within seconds of image acquisition.

  13. Xeroradiography for intraoral dental radiology. A process description.

    PubMed

    Jeromin, L S; Geddes, G F; White, S C; Gratt, B M

    1980-02-01

    A novel x-ray imaging system for intraoral dental radiography is described. The imaging process is based on xeroradiographic principles. The surface of a small selenium photoreceptor is electrically charged. After insertion into a light-tight cassette, the photoreceptor is placed intraorally and x-ray exposed like film. The resultant electrostatic charge image is developed in a processor using liquid toner. The toner image is then transferred from the photoreceptor and fixed to a white plastic substrate for viewing. After cleaning, the photoreceptor is available for reuse. In contrast to film images, xeroradiographic images are exposed and processed sequentially. Processing time is approximately 20 seconds. Two image characteristics--edge enhancement and deletion--are primarily responsible for many advantageous qualities of xeroradiographic images over film images. An experimental processor was tested successfully at two dental schools. PMID:6928292

  14. Dental Implant Systems

    PubMed Central

    Oshida, Yoshiki; Tuna, Elif B.; Aktören, Oya; Gençay, Koray

    2010-01-01

    Among various dental materials and their successful applications, a dental implant is a good example of the integrated system of science and technology involved in multiple disciplines including surface chemistry and physics, biomechanics, from macro-scale to nano-scale manufacturing technologies and surface engineering. As many other dental materials and devices, there are crucial requirements taken upon on dental implants systems, since surface of dental implants is directly in contact with vital hard/soft tissue and is subjected to chemical as well as mechanical bio-environments. Such requirements should, at least, include biological compatibility, mechanical compatibility, and morphological compatibility to surrounding vital tissues. In this review, based on carefully selected about 500 published articles, these requirements plus MRI compatibility are firstly reviewed, followed by surface texturing methods in details. Normally dental implants are placed to lost tooth/teeth location(s) in adult patients whose skeleton and bony growth have already completed. However, there are some controversial issues for placing dental implants in growing patients. This point has been, in most of dental articles, overlooked. This review, therefore, throws a deliberate sight on this point. Concluding this review, we are proposing a novel implant system that integrates materials science and up-dated surface technology to improve dental implant systems exhibiting bio- and mechano-functionalities. PMID:20480036

  15. Common Errors in Digital Panoramic Radiographs of Patients with Mixed Dentition and Patients with Permanent Dentition

    PubMed Central

    Peretz, Benjamin; Gotler, Maya; Kaffe, Israel

    2012-01-01

    Purpose. To compare errors in digital panoramic radiographs of permanent and mixed dentitions. Methods. 143 and 146 digital radiographs of mixed and permanent dentitions were examined. Results. Significantly fewer errors presented in the mixed dentition. Positioning too forward significantly prevalent in the mixed dentition; slumped position and nonpositioning of chin properly were significantly prevailed in the permanent dentition. Blurred or shortened upper incisors were significantly more prevalent in the mixed dentition. Diagnostic ability could be improved by manipulating the brightness or contrast in nearly 45% of all radiographs. In the mixed dentition, tilting the chin down and a slumped position made the lower incisors significantly nondiagnostic. In the permanent dentition, tilting the chin down made the lower incisors to be significantly nondiagnostic. Conclusions. More errors were prevalent in panoramic radiographs of permanent dentitions. Properly positioning the patient is the most important factor in preventing a cascade of errors. PMID:22505905

  16. A Master-Slave Surveillance System to Acquire Panoramic and Multiscale Videos

    PubMed Central

    Shi, Hao

    2014-01-01

    This paper describes a master-slave visual surveillance system that uses stationary-dynamic camera assemblies to achieve wide field of view and selective focus of interest. In this system, the fish-eye panoramic camera is capable of monitoring a large area, and the PTZ dome camera has high mobility and zoom ability. In order to achieve the precise interaction, preprocessing spatial calibration between these two cameras is required. This paper introduces a novel calibration approach to automatically calculate a transformation matrix model between two coordinate systems by matching feature points. In addition, a distortion correction method based on Midpoint Circle Algorithm is proposed to handle obvious horizontal distortion in the captured panoramic image. Experimental results using realistic scenes have demonstrated the efficiency and applicability of the system with real-time surveillance. PMID:24729750

  17. Mandibular Inferior Cortical Bone Thickness on Panoramic Radiographs in Patients using Bisphosphonates

    PubMed Central

    Torres, Sandra R.; Chen, Curtis S. K.; Leroux, Brian G.; Lee, Peggy P.; Hollender, Lars G.; Lloid, Michelle; Drew, Shane Patrick; Schubert, Mark M.

    2015-01-01

    Objective To detect dimensional changes in the mandibular cortical bone associated with bisphosphonate (BP) use and to correlate the measurements of the cortical bone with the cumulative dose of BP therapy. Methods Mandibular inferior cortical bone thickness (MICBT) was measured under the mental foramen from panoramic radiographs of subjects using BP with and without bisphosphonate related osteonecrosis of the jaws (BRONJ) and controls. Results The highest mean MICBT was observed in BRONJ subjects 6.81 (± 1.35 mm), when compared to subjects using BP 5.44 (± 1.09 mm) and controls 4.79 (± 0.85 mm; p<0.01). The mean MICBT of BRONJ subjects was significantly higher than that of subjects using BP without BRONJ. There was a correlation between MICBT and cumulative dose of zolendronate. Conclusion The MICBT on panoramic radiograph is a potentially useful tool for the detection of dimensional changes associated with BP therapy. PMID:25864820

  18. Panoramic-image-based rendering solutions for visualizing remote locations via the web

    NASA Astrophysics Data System (ADS)

    Obeysekare, Upul R.; Egts, David; Bethmann, John

    2000-05-01

    With advances in panoramic image-based rendering techniques and the rapid expansion of web advertising, new techniques are emerging for visualizing remote locations on the WWW. Success of these techniques depends on how easy and inexpensive it is to develop a new type of web content that provides pseudo 3D visualization at home, 24-hours a day. Furthermore, the acceptance of this new visualization medium depends on the effectiveness of the familiarization tools by a segment of the population that was never exposed to this type of visualization. This paper addresses various hardware and software solutions available to collect, produce, and view panoramic content. While cost and effectiveness of building the content is being addressed using a few commercial hardware solutions, effectiveness of familiarization tools is evaluated using a few sample data sets.

  19. Comparison of periapical radiography with cone beam computed tomography in the diagnosis of vertical root fractures in teeth with metallic post

    PubMed Central

    Takeshita, Wilton Mitsunari; Iwaki, Lilian Cristina Vessoni; da Silva, Mariliani Chicarelli; Sabio, Sergio; Albino, Paulo Ricardo Febrairo

    2014-01-01

    Aim: To compare the diagnostic accuracy of conventional periapical radiography and cone beam computed tomography (CBCT) in detecting vertical root fracture (VRF) in tooth with metallic post (MP). Materials and Methods: Twenty endodontically-treated teeth received MPs, artificial fractures were created in 10 teeth, and they were all examined with tomography and radiography. The sample consisted of periapical radiography with post and without post, and tomography with post and without post; each group with five fractured and five non-fractured teeth. The images were evaluated by three dental/maxillofacial radiologists and statistical validations were carried out using receiver operating characteristic (ROC) analysis. Results: Sensitivity and specificity of the area under the ROC (Az) of tomography with post (Az = 0.953) and without post (Az = 0.956) were significantly higher than those of periapical radiography with post (Az = 0.753) and without post (Az = 0.778). Conclusion: CBCT was more accurate than conventional periapical radiography in detecting VRF. PMID:24944444

  20. INDUSTRIAL RADIOGRAPHY COURSE, INSTRUCTORS' GUIDE. VOLUME 2.

    ERIC Educational Resources Information Center

    Texas A and M Univ., College Station. Engineering Extension Service.

    INFORMATION RELATIVE TO THE LESSON PLANS IN "INDUSTRIAL RADIOGRAPHY COURSE, INSTRUCTOR'S GUIDE, VOLUME I" (VT 003 565) IS PRESENTED ON 52 INFORMATION SHEETS INCLUDING THE SUBJECTS SHIELDING EQUATIONS AND LOGARITHMS, METAL PROPERTIES, FIELD TRIP INSTRUCTIONS FOR STUDENTS, WELDING SYMBOLS AND SIZES, SAMPLE REPORT FORMS, AND TYPICAL SHIPPING…

  1. Safety Testing of Industrial Radiography Devices

    SciTech Connect

    Trapp, D.J.

    1999-09-29

    The Nuclear Regulatory Commission contracted the Savannah River Technology Center to verify the relevancy of the 10 CFR Part 34 requirements for the normal use of portable gamma radiography systems and to propose recommendations for changes or modifications to the requirements.

  2. Relationship between the elongated styloid process in panoramic radiographs and some of the general health conditions in patients over 40 years of age in the Iranian population

    PubMed Central

    Ghafari, Roshanak; Hosseini, Bahareh; Shirani, Amir Mansour; Manochehrifar, Hamed; Saghaie, Sima

    2012-01-01

    Background: The styloid process and the attached ligaments have the potential for calcification and ossification in specific conditions. The purpose of this study was to evaluate the relationship between the elongated styloid process (ESP) frequency and some of the systemic health factors of patients over 40 years of age. Materials and Methods: In this analytical-descriptive study, 296 panoramic radiographs of patients over 40 years of age (165 female and 131 male) referred to the Dental School of Khorasgan Azad University were selected. The length of the styloid process was measured by a special ruler and recorded in a questionnaire form. Other data such as sex, age, height, weight, blood pressure, heartbeat and the number of teeth present in the mouth were also recorded. The lengths equal to or more than 30 mm on the radiographs were considered as ESP. Data analysis were done by independent t-test, Pearson correlation coefficient and Chi-square test at a significance level of < 0.05. Results: ESP was observed in 135 cases (45.6%). There was a significant relationship between ESP and the body height, weight and the blood pressure, but there was no significant correlation between ESP, the heartbeat and the number of teeth present in the mouth. Conclusion: Because of the significant relationship between the length of the styloid process and the blood pressure, height and weight it is reasonable to evaluate a patient's systemic health conditions when radiographic signs of ESP are observed. PMID:23814562

  3. Evaluation of the accuracy of linear and angular measurements on panoramic radiographs taken at different positions

    PubMed Central

    Nikneshan, Sima; Sharafi, Mohamad

    2013-01-01

    Purpose This study assessed the accuracy of linear and angular measurements on panoramic radiographs taken at different positions in vitro. Materials and Methods Two acrylic models were fabricated from a cast with normal occlusion. Straight and 75° mesially and lingually angulated pins were placed, and standardized panoramic radiographs were taken at standard position, at an 8° downward tilt of the occlusal plane compared to the standard position, at an 8° upward tilt of the anterior occlusal plane, and at a 10° downward tilt of the right and left sides of the model. On the radiographs, the length of the pins above (crown) and below (root) the occlusal plane, total pin length, crown-to-root ratio, and angulation of pins relative to the occlusal plane were calculated. The data were subjected to repeated measures ANOVA and LSD multiple comparisons tests. Results Significant differences were noted between the radiographic measurements and true values in different positions on both models with linear (P<0.001) and those with angulated pins (P<0.005). No statistically significant differences were observed between the angular measurements and baselines of the natural head posture at different positions for the linear and angulated pins. Conclusion Angular measurements on panoramic radiographs were sufficiently accurate and changes in the position of the occlusal plane equal to or less than 10° had no significant effect on them. Some variations could exist in the pin positioning (head positioning), and they were tolerable while taking panoramic radiographs. Linear measurements showed the least errors in the standard position and 8° upward tilt of the anterior part of the occlusal plane compared to other positions. PMID:24083213

  4. Higher-order pupil aberrations in wide-angle and panoramic optical systems

    NASA Astrophysics Data System (ADS)

    Fallah, Hamid R.; Maxwell, Jonathan

    1996-08-01

    In optical systems with modest fields of view, pupil spherical aberration and pupil coma are the principal pupil aberrations of significance, but at extreme fields of view, astigmatic effects and field curvature and distortion effects of the pupil imagery play a part in understanding the subtleties of oblique object-image imagery. Biogon and fisheye wide angle lens systems have been investigated for their pupil aberration properties, along with the investigation of similar effects in a panoramic optical system.

  5. Influence of the intergonial distance on image distortion in panoramic radiographs

    PubMed Central

    Ladeira, DBS; Cruz, AD; Almeida, SM; Bóscolo, FN

    2012-01-01

    Objectives The aim of this study was to evaluate the influence of the intergonial distance during the formation of panoramic radiographic images by means of horizontal and vertical measurements. Methods 30 macerated mandibles were categorized into 3 different groups (n = 10) according to their intergonial distances as follows: G1, mean distance 8.2 cm, G2, mean distance 9.0 cm and G3, mean distance 9.6 cm. Three metal spheres 0.198 cm in diameter and placed at an incline using an isosceles triangle were separately placed over the internal and external surfaces of the mandibles before radiographic exposure for the purpose of taking the horizontal and vertical measurements. The occlusal planes of the mandibles were horizontally placed on the chin rest of the panoramic machine Orthopantomograph® OP 100 (Instrumentarium Imaging, Tuusula, Finland) and were then radiographed. In the panoramic radiographs, an expert radiologist measured the distances between the metal spheres in the horizontal and vertical directions using a digital caliper. The data were tabled and statistically analysed by Student's t-test and analysis of variance with Tukey post-test (α = 0.05). Results In all three groups magnification of the distances between spheres was observed when compared with the real distance in both horizontal and vertical measurements (p < 0.05). Differences in both horizontal and vertical measurements were observed between the different regions (p < 0.05), however there were no differences between groups in the same region (p > 0.05). Differences between horizontal and vertical measurements were observed in different regions in all evaluated groups (p < 0.05). Conclusion The intergonial distance is a factor that had no influence on image formation in the panoramic radiograph. PMID:22282504

  6. Perception of anatomical structures in digitally filtered and conventional panoramic radiographs: a clinical evaluation

    PubMed Central

    Baksi, BG; Alpöz, E; Soğur, E; Mert, A

    2010-01-01

    Objectives The aims of the study were to compare subjective image quality of clinical images obtained with a storage phosphor plate (SPP)-based digital and conventional film-based panoramic system for the visualization of various anatomical structures and to evaluate the effect of various processing algorithms on image interpretation. Methods Panoramic radiographs were taken in 42 patients both with film and with a SPP system. SPP images were treated with shadow, sharpen, negative, greyscale sigma and greyscale exponential filters. Four observers subjectively evaluated films and unfiltered and filtered SPP images for the visibility of anatomical structures with various radiodensities as well as for overall image quality on a three-point rating scale. The statistical methods used were Kruskal–Wallis, odds ratio analysis and Cohen's kappa. Results No statistically significant difference was found between film and unfiltered digital images except for low-contrast structures (P > 0.05). Film images were preferred for the visibility of low-contrast structures (P < 0.05). Best overall image quality was obtained with sharpened images (P < 0.05) followed by films and unfiltered digital images. Among all filtered images, sharpened ones received the highest ratings for the visibility of all anatomical structures (P < 0.05). The intra- and interobserver agreement ranged between moderate and substantial and between fair and moderate, respectively. Conclusions Film and unfiltered SPP-based panoramic images performed equally well in terms of overall quality; however, films were best for the perception of low-contrast structures. The sharpening filter may be recommended for enhancing SPP panoramic images to improve the visual perception of most of the anatomical structures as well as overall quality. PMID:20841460

  7. Education About Dental Hygienists' Roles in Public Dental Prevention Programs: Dental and Dental Hygiene Students' and Faculty Members' and Dental Hygienists' Perspectives.

    PubMed

    Pervez, Anushey; Kinney, Janet S; Gwozdek, Anne; Farrell, Christine M; Inglehart, Marita R

    2016-09-01

    In 2005, Public Act No. 161 (PA 161) was passed in Michigan, allowing dental hygienists to practice in approved public dental prevention programs to provide services for underserved populations while utilizing a collaborative agreement with a supervising dentist. The aims of this study were to assess how well dental and dental hygiene students and faculty members and practicing dental hygienists have been educated about PA 161, what attitudes and knowledge about the act they have, and how interested they are in additional education about it. University of Michigan dental and dental hygiene students and faculty members, students in other Michigan dental hygiene programs, and dental hygienists in the state were surveyed. Respondents (response rate) were 160 dental students (50%), 63 dental hygiene students (82%), 30 dental faculty members (26%), and 12 dental hygiene faculty members (52%) at the University of Michigan; 143 dental hygiene students in other programs (20%); and 95 members of the Michigan Dental Hygienists' Association (10%). The results showed that the dental students were less educated about PA 161 than the dental hygiene students, and the dental faculty members were less informed than the dental hygiene faculty members and dental hygienists. Responding dental hygiene faculty members and dental hygienists had more positive attitudes about PA 161 than did the students and dental faculty members. Most of the dental hygiene faculty members and dental hygienists knew a person providing services in a PA 161 program. Most dental hygiene students, faculty members, and dental hygienists wanted more education about PA 161. Overall, the better educated about the program the respondents were, the more positive their attitudes, and the more interested they were in learning more. PMID:27587574

  8. Computer-aided system for measuring the mandibular cortical width on panoramic radiographs in osteoporosis diagnosis

    NASA Astrophysics Data System (ADS)

    Arifin, Agus Zainal; Asano, Akira; Taguchi, Akira; Nakamoto, Takashi; Ohtsuka, Masahiko; Tanimoto, Keiji

    2005-04-01

    Osteoporotic fractures are associated with substantial morbidity, increased medical cost and high mortality risk. Several equipments of bone assessment have been developed to identify individuals, especially postmenopausal women, with high risk of osteoporotic fracture; however, a large segment of women with low skeletal bone mineral density (BMD), namely women with high risk of osteoporotic fractures, cannot be identified sufficiently because osteoporosis is asymptomatic. Recent studies have been demonstrating that mandibular inferior cortical width manually measured on panoramic radiographs may be useful for the identification of women with low BMD. Automatic measurement of cortical width may enable us to identify a large number of asymptomatic women with low BMD. The purpose of this study was to develop a computer-aided system for measuring the mandibular cortical width on panoramic radiographs. Initially, oral radiologists determined the region of interest based on the position of mental foramen. Some enhancing image techniques were applied so as to measure the cortical width at the best point. Panoramic radiographs of 100 women who had BMD assessments of the lumbar spine and femoral neck were used to confirm the efficacy of our new system. Cortical width measured with our system was compared with skeletal BMD. There were significant correlation between cortical width measured with our system and skeletal BMD. These correlations were similar with those between cortical width manually measured by the dentist and skeletal BMD. Our results suggest that our new system may be useful for mass screening of osteoporosis.

  9. Construction of panoramic image mosaics based on affine transform and graph cut

    NASA Astrophysics Data System (ADS)

    Wang, Haiying; Qin, Kaihuai

    2010-08-01

    Image-based rendering has been a popular technique to simulate a visually rich telepresence and virtual reality experience. The construction of panoramic image mosaics is an indispensable step in image-based rendering systems like QuickTime VR and Surround Video. The conventional methods for creating panoramic image mosaics with regular photographic or video images use geometrical feature points and optimization to the overlapped areas of the two consecutive images, and then align and mosaic the corresponding areas using the blending or stitching algorithm. This paper introduces a novel and efficient method to build panoramic image mosaics. The proposed method divides the overlapped areas of the consecutive images into several sub-areas. The feature point, whose gradient value of intensity is the maximum in the sub-area can be found easily. After selecting these feature points, we warp the images using an affine transformation based on point set matching. Then the graph cut algorithm is used to build the seamless image mosaic which makes the overlapped areas containing no visible ghosting or blurred details. It is shown by the experiments that the new method can obtain mosaics of high quality and reduce the computing time.

  10. Correlation of Condylar Guidance Determined by Panoramic Radiographs to One Determined by Conventional Methods

    PubMed Central

    Godavarthi, A Sowjanya; Sajjan, M C Suresh; Raju, A V Rama; Rajeshkumar, P; Premalatha, Averneni; Chava, Narayana

    2015-01-01

    Background: To evaluate the feasibility of using panoramic radiographs as an alternative to an interocclusal recording method for determining the condylar guidance in dentate and edentulous conditions. Materials and Methods: 20 dentulous individuals with an age range of 20-30 years and 20 edentulous patients of 40-65 years were selected. An interocclusal bite registration was done in protrusive position for all the subjects. Orthopantomographs were made for all patients in open mouth position. Hanau articulator was modified to record the angulations to the accuracy of 1°. Tracing of glenoid fossa on radiograph was done to measure the condylar guidance angles. Readings were recorded and analyzed by Freidman’s test and t-test. Results: Condylar guidance values obtained by the interocclusal method and radiographic method in dentate individuals on the right side and left side 40.55°, and 37.1°, and 40.15°, and 34.75°, respectively. In the edentulous individuals, the values on the right side and left side was 36.7° and 36.1° and 35.95° and 33.6,° respectively. The difference was statistically significant (P = < 0.001) in dentate group and was not statistically significant (P = 0.6493) in edentulous group. Conclusion: Panoramic radiograph can be used as an alternative to interocclusal technique only in edentulous patients. Further studies comparing panoramic radiograph to jaw tracking devices would substantiate the results of this study. PMID:26464554

  11. A comparative study of the effective radiation doses from cone beam computed tomography and plain radiography for sialography

    PubMed Central

    Jadu, F; Yaffe, MJ; Lam, EWN

    2010-01-01

    Objectives As a first step in developing a protocol for multidimensional sialography using cone beam CT (CBCT), the objective of this study was to compare the effective radiation doses from sialography of the parotid and submandibular glands using plain radiography and CBCT. Methods The effective doses were calculated from dose measurements made at 25 selected locations in the head and neck of a radiation analogue dosimeter (RANDO) phantom, using International Commission on Radiological Protection 2007 tissue weighting factors. Results The effective dose (E) changed in relationship to changes in CBCT field of view (FOV), peak kilovoltage (kVp) and milliamperage (mA). Specifically, E decreased from a maximum of 932 μSv (30 cm FOV, 120 kVp, 15 mA) to 60 μSv (15 cm FOV, 80 kVp, 10 mA) for a parotid gland study and to 148 μSv (15 cm FOV, 80 kVp, 10 mA) for a submandibular study. The collective series of plain radiographs made during sialography of the parotid and submandibular glands yielded effective doses of 65 μSv and 156 μSv, respectively. The plain parotid gland series included one panoramic, two anterior–posterior skull and four lateral skull radiographs, whereas the submandibular gland series included one panoramic, one standard mandibular occlusal and four lateral skull radiographs. Conclusion The effective doses from CBCT examinations centred on the parotid and submandibular glands were similar to those calculated for plain radiograph sialography when a 15 cm FOV was chosen in combination with exposure conditions of 80 kVp and 10 mA. PMID:20587648

  12. Dental Laboratory Technician.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. Center on Education and Training for Employment.

    This document, which is designed for use in developing a tech prep competency profile for the occupation of dental laboratory technician, lists technical competencies and competency builders for 13 units pertinent to the health technologies cluster in general and 8 units to the occupation of dental laboratory technician. The following skill areas…

  13. Dental Charting. Student's Manual.

    ERIC Educational Resources Information Center

    Weaver, Trudy Karlene; Apfel, Maura

    This manual is part of a series dealing with skills and information needed by students in dental assisting. The individualized student materials are suitable for classroom, laboratory, or cooperative training programs. This student manual contains four units covering the following topics: dental anatomical terminology; tooth numbering systems;…

  14. Dental Assisting Program Guide.

    ERIC Educational Resources Information Center

    Georgia Univ., Athens. Dept. of Vocational Education.

    This program guide contains the standard dental assisting curriculum for technical institutes in Georgia. The curriculum encompasses the minimum competencies required for entry-level dental assistants, and includes job skills in the technical areas of preventive dentistry; four-handed dentistry; chairside assisting with emphasis in diagnostics,…

  15. Dental Fear Among University Employees: Implications for Dental Education.

    ERIC Educational Resources Information Center

    Kaakko, Tarja; Milgrom, Peter; Coldwell, Susan E.; Getz, Tracy; Weinstein, Philip; Ramsay, Douglas S.

    1998-01-01

    A survey of 270 University of Washington permanent employees who were potential candidates for teaching clinics, found dental anxiety prevalent, correlating with poorer perceived dental health, longer intervals between dental appointments, higher frequency of past fear behaviors, more physical symptoms during last dental injection, and more…

  16. The future dental workforce?

    PubMed

    Gallagher, J E; Wilson, N H F

    2009-02-28

    The Editor-in-Chief of the BDJ has previously raised important questions about dental workforce planning and the implications for dental graduates of recent changes and pressures. It is now time to revisit this issue. Much has changed since the last workforce review in England and Wales, and the rate of change is in all probability set to increase. First, at the time of writing this paper the momentous step of including dental care professionals (DCPs) on General Dental Council (GDC) registers in the United Kingdom has recently been completed. Second, the Scope of Practice of all dental professionals has been under consultation by the General Dental Council, and research evidence suggests that greater use should be made of skill-mix in the dental team. Third, within England, Lord Darzi has just published the 'Final Report of the NHS Next Stage Review', which emphasises 'quality care' and 'team-working' as key features of healthcare; this report was accompanied by an important document entitled 'A High Quality Workforce', in which plans for local workforce planning within the NHS are outlined, placing responsibilities at national, local and regional levels. Fourth, policy makers across the UK are wrestling with addressing oral health needs, promoting health and facilitating access to dental care, all of which have implications for the nature and shape of the dental workforce. Fifth, with the impact of globalisation and European policies we are net gainers of dentists as well as having more in training. Sixth, although there have been reviews and policy initiatives by regulatory, professional and other bodies in support of shaping the dental workforce, there has been little serious consideration of skill-mix and funding mechanisms to encourage team-working. Together, these events demand that we enter a fresh debate on the future dental workforce which should extend beyond professional and national boundaries and inform workforce planning. This debate is of great

  17. Health Instruction Packages: Permanent Teeth, Dental Deposits, and Dental Instruments. Dientes Permanentes, Depositos Dentales y Instrumentos Dentales.

    ERIC Educational Resources Information Center

    Lind, Patricia; Germano, Catherine

    These five learning modules use text interspersed with illustrations and reinforcement exercises to instruct dental aide and dental hygiene students about jaw bones and gums, dental deposits, and dental instruments. The first four modules were prepared by Patricia Lind in both Spanish and English. "The Gum and Bone of Permanent Teeth" ("La Encia y…

  18. Is dosimetry still a necessity in current dental practice?

    PubMed

    Reddy, S S; Rakesh, N; Chauhan, Pallavi; Clint, Joseph Ben; Sharma, Shivani

    2015-12-01

    Today, dentists have a wide range of imaging modalities to choose from, the film based techniques, digital techniques, and the recent introduction of 3D volumetric or cone beam computed tomography (CBCT). The inherent design features of the new generation dental x-ray equipment has significantly improved over the years with no evidence of substandard x-ray units in operation. In dental facilities radiological workload is comparatively low, newer radiation equipments and accessories follow safety guidelines and employ better radiation protection measures for the patient and the operator. Dentists' knowledge and expertise in radiation protection measures is good, enabling them to carry out riskfree radiation procedures in their practice. Therefore, the present study is aimed at assessing the need for dosimeters in current dental scenario. 'Is there currently a significant risk from dental radiography to merit the use of personal dosimetery in dental practice. 'Dental health professionals (Oral radiologists) and radiographic assistants of fourteen dental colleges in Karnataka state participated in this questionnaire study. The questionnaire consisted of the following questions--the make, type, year of manufacture of radiographic machines used in their setup, number of radiographs made per day in the institution, type of receptors used, number of personnel at risk for radiation exposure, radiation protection measures used, regular monitoring by personal dosimeters, equivalent dosage readings for the past 12 months and whether the reading of thermoluminescent dosimeters (TLD) for any personnel had exceeded the recommended exposure value in the last 3 years. Dosimetry records of the radiology staff in the last three years shows doses no more than 1.50 mSv per year. The various institutions' dose (person mSv) was in the range of 3.70 mSv-3.90 mSv. Personal monitoring for Dentists can be omitted in the dental colleges since the estimated dose of oral radiologists

  19. Prevalence of Third Molar Agenesis: Associated Dental Anomalies in Non-Syndromic 5923 Patients.

    PubMed

    Sujon, Mamun Khan; Alam, Mohammad Khursheed; Rahman, Shaifulizan Abdul

    2016-01-01

    The aim of this study was to investigate the prevalence of third molar agenesis and other associated dental anomalies in Bangladeshi population and to investigate the relationship of other dental anomalies with the third molar presence/agenesis. A retrospective study was performed using panoramic radiographs of 5923 patients, who ranged in age from 10 to 50 years. All radiographs were analyzed by Planmeca Romexis® 3.0 software (Planmeca Oy, Helsinki, Finland). Pearson chi-square and one way ANOVA (Post Hoc) test were conducted. The prevalence of third molar agenesis was 38.4%. The frequency of third molar agenesis was significantly higher in females than males (p <0.025). Third molar agenesis was significantly more prevalent in maxilla as compared to mandible (p <0.007). The prevalence of other dental anomalies was 6.5%, among them hypodontia was 3.1%. Prevalence of third molar agenesis varies in different geographic region. Among the other dental anomalies hypodontia was more prevalent. PMID:27580050

  20. Comparison among dental, skeletal and chronological development in HIV-positive children: a radiographic study.

    PubMed

    Holderbaum, Rejane Maria; Veeck, Elaine Bauer; Oliveira, Helena Willhelm; Silva, Carmem Lúcia da; Fernandes, Angela

    2005-01-01

    The goal of this study was to evaluate skeletal, dental and chronological development in an HIV-positive group of children, as compared with a control group, during a four-year period. Panoramic radiographs and hand and wrist radiographs of 60 children were taken. The children, of both sexes, aged 5 years and 2 months to 15 years and 5 months, were selected as follows: 30 HIV-positive volunteers who had acquired the disease vertically, and 30 volunteers who did not present the HIV infection or any other systemic disease. All radiographs were technically standardized and analyzed according to criteria established by Nolla (dental age), Greulich and Pyle (bone age), and Eklöf and Ringertz (bone age). The results were submitted to Student's t-test at a 5% level of significance. Based on the comparison between the chronological age and the dental or the skeletal age, significant differences were observed between HIV-positive and HIV-negative children, both in 1999 and in 2003 (p < or = 0.05). Considering the results obtained with the methodology used, it was concluded that HIV-positive children of both sexes presented delayed bone development despite the administration of antiretroviral drugs, and that HIV-positive female children presented younger dental ages compared with their chronological ages in 1999 and in 2003; and HIV-positive males, in 1999. PMID:16308610

  1. Development of dental charts according to tooth development and eruption for Turkish children and young adults

    PubMed Central

    Afşin, Hüseyin; Ozaslan, Abdi; Karadayı, Şükriye

    2014-01-01

    Purpose In this study, we aimed to develop dental charts for Turkish children and young adults of both genders within the age group of 4.5-22.5 years according to tooth mineralization and eruption in a format similar to that proposed by AlQahtani et al. Materials and Methods In total, 753 digital panoramic radiographs from 350 males and 403 females were assessed. The permanent teeth were evaluated according to the classification system described by Demirjian et al. The eruption stage was assessed with Bengston's system, which was modified by AlQahtani et al at four points. Results Teeth generally developed earlier in females than in males. This was particularly notable in the age group of 5-14 years. However, this difference was usually visible in only one stage, not in all teeth. It has been determined that the mixed dentition period ended with the shedding of the second deciduous molars in both genders. Conclusion The dental charts presented here included information that could be beneficial to dental clinicians in making appropriate diagnosis and planning orthodontic and surgical procedures. These charts also provided datasets for preliminary dental age estimation in Turkish children and young adults. PMID:24944959

  2. Digital radiography: a focus on clinical utility

    SciTech Connect

    Price, R.R.; Rollo, F.D.; Monahan, W.G.; James, A.E. Jr.

    1982-01-01

    This book is interesting and timely in that it covers the new and exciting area of digital radiography. The book begins with chapters on the physics, instrumentation, and terminology of digital radiography. Then cost-benefit ratios, legal implication, and outpatient vs. inpatient studies are discussed. The clinical chapters follow. These are applicable to the head and neck, heart, lungs, kidneys, peripheral arteries, and pediatric population. Discussion then centers on intraarterial digital subtraction, clinical experience at Wisconsin, nonangiography application of digital radiology in children, and analog film-screen subtraction intravenous angiography. The book ends by briefly discussing microwave imaging, nuclear magnetic resonance, emission tomography, real-time and Doppler sonography, analog tomography, and the future photoelectric radiology department.

  3. Point projection radiography with the FXI

    SciTech Connect

    Budil, K.; Perry, T.S.; Alvarez, S.A.

    1996-05-06

    Radiography techniques utilizing large area x-ray sources (typically {<=} 7 keV) and pinhole-imaging gated x-ray diagnostics have long been used at the Nova laser facility. However, for targets requiring higher energy x-ray backlighters (> 9 keV), low conversion efficiencies and pinhole losses combine to make this scheme unworkable. The technique of point projection radiography has been improved upon to make imaging at high x-ray energies feasible. In this scheme a {open_quotes}point{close_quotes} source of x-rays, usually a small diameter ({<=}25 {mu}m) fiber, is illuminated with a single, 100 ps pulse from the Nova laser. A gated x-ray imager with a 500 ps electronic gate width is used to record the projected image. The experimental challenges this technique presents and experimental results will be discussed.

  4. Characterizing flash-radiography source spots.

    PubMed

    Ekdahl, Carl

    2011-12-01

    Flash radiography of large hydrodynamic experiments driven by high explosives is a venerable diagnostic technique in use at many laboratories. The size of the radiographic source spot is often quoted as an indication of the resolving power of a particular flash-radiography machine. A variety of techniques for measuring spot size have evolved at the different laboratories, as well as different definitions of spot size. Some definitions are highly dependent on the source spot intensity distributions, and not necessarily well correlated with resolution. The concept of limiting resolution based on bar target measurements is introduced, and shown to be equivalent to the spatial wavenumber at a modulation transfer function value of 5%. This resolution is shown to be better correlated with the full width at half-maximum of the spot intensity distribution than it is with other definitions of spot size. PMID:22193263

  5. Deflection evaluation using time-resolved radiography

    SciTech Connect

    Fry, D.A.; Lucero, J.P.

    1990-01-01

    Time-resolved radiography is the creation of an x-ray image for which both the start-exposure and stop-exposure times are known with respect to the event under study. The combination of image and timing are used to derive information about the event. We have applied time-resolved radiography to evaluate motions of explosive-driven events. In the particular application discussed here, our intent is to measure maximum deflections of the components involved. Exposures are made during the time just before to just after the event of interest occurs. A smear or blur of motion out to its furthest extent is recorded on the image. Comparison of the dynamic images with static images allows deflection measurements to be made. 2 figs.

  6. A system for fast neutron radiography

    SciTech Connect

    Klann, R.T.

    1996-05-01

    A system has been designed and a neutron generator installed to perform fast neutron radiography. With this sytem, objects as small as a coin or as large as a waste drum can be radiographed. The neutron source is an MF Physics A-711 neutron generator which produces 3x10{sup 10} neutrons/second with an average energy of 14.5 MeV. The radiography system uses x-ray scintillation screens and film in commercially available cassettes. The cassettes have been modified to include a thin sheet of plastic to convert neutrons to protons through elastic scattering from hydrogen and other low Z materials in the plastic. For film densities from 1.8 to 3.0, exposures range from 1.9x10{sup 7} to 3.8x10{sup 8} n/cm{sup 2} depending on the type of screen and film.

  7. Wizardry and radiography: a clinical case.

    PubMed

    Desrentes, M

    1990-10-01

    The author encountered a patient who had undergone various sorcery and wizardry practices. At radiography performed because of lower back pain, 100 sharp metal foreign bodies (such as needles and sharpened paper clips) were found scattered between his neck and pelvis. The patient evidently swallowed some of the objects to gain protection against aggression from humans or spiritual beings. However, the means of introduction of some of the objects (eg, the needles in the neck) cannot be determined. PMID:2399308

  8. Digital radiography: Present detectors and future developments

    SciTech Connect

    Perez-Mendez, V.

    1990-08-01

    Present detectors for digital radiography are of two classes: real time detectors and storage (non real time) types. Present real time detectors consist of image intensifier tubes with an internal cesium iodide layer x-ray converter. Non real time detectors involve linear sweep arrays or storage detectors such as film. Future detectors discussed here can be of both types utilizing new technologies such as hydrogenated amorphous silicon photodiode arrays coupled to thin film transistor arrays. 17 refs., 10 figs.

  9. Progress in thermal neutron radiography at LENS

    NASA Astrophysics Data System (ADS)

    Jenkins, Jack; Low Energy Neutron Source (LENS) at Indiana University Collaboration

    2014-09-01

    An end station for thermal neutron radiography and tomography is in operation at the Indiana University LENS facility. Neutrons from proton-induced nuclear reactions in Beryllium are moderated and collimated into a beam which is attenuated by a scanned object on a remotely-controlled rotating table. Neutron signal is then converted to a light signal with a ZnS scintillating screen and recorded in a cooled CCD. The author has performed diagnostics on the radiography hardware and software and has tested the system's capabilities by imaging a stack of high density polyethylene cubes with diverse inlet holes and grooves on an 80/20 aluminum base. The resolution of the radiographs are seen to be less than 1mm and 3D rending software is capable of reconstructing the internal structure of the aluminum. An end station for thermal neutron radiography and tomography is in operation at the Indiana University LENS facility. Neutrons from proton-induced nuclear reactions in Beryllium are moderated and collimated into a beam which is attenuated by a scanned object on a remotely-controlled rotating table. Neutron signal is then converted to a light signal with a ZnS scintillating screen and recorded in a cooled CCD. The author has performed diagnostics on the radiography hardware and software and has tested the system's capabilities by imaging a stack of high density polyethylene cubes with diverse inlet holes and grooves on an 80/20 aluminum base. The resolution of the radiographs are seen to be less than 1mm and 3D rending software is capable of reconstructing the internal structure of the aluminum. NSF.

  10. Toward panoramic in situ mapping of action potential propagation in transgenic hearts to investigate initiation and therapeutic control of arrhythmias

    PubMed Central

    Dura, Miroslav; Schröder-Schetelig, Johannes; Luther, Stefan; Lehnart, Stephan E.

    2014-01-01

    To investigate the dynamics and propensity for arrhythmias in intact transgenic hearts comprehensively, optical strategies for panoramic fluorescence imaging of action potential (AP) propagation are essential. In particular, mechanism-oriented molecular studies usually depend on transgenic mouse hearts of only a few millimeters in size. Furthermore, the temporal scales of the mouse heart remain a challenge for panoramic fluorescence imaging with heart rates ranging from 200 min−1 (e.g., depressed sinus node function) to over 1200 min−1 during fast arrhythmias. To meet these challenging demands, we and others developed physiologically relevant mouse models and characterized their hearts with planar AP mapping. Here, we summarize the progress toward panoramic fluorescence imaging and its prospects for the mouse heart. In general, several high-resolution cameras are synchronized and geometrically arranged for panoramic voltage mapping and the surface and blood vessel anatomy documented through image segmentation and heart surface reconstruction. We expect that panoramic voltage imaging will lead to novel insights about molecular arrhythmia mechanisms through quantitative strategies and organ-representative analysis of intact mouse hearts. PMID:25249982

  11. Advances in dental materials.

    PubMed

    Vaderhobli, Ram M

    2011-07-01

    The use of materials to rehabilitate tooth structures is constantly changing. Over the past decade, newer material processing techniques and technologies have significantly improved the dependability and predictability of dental material for clinicians. The greatest obstacle, however, is in choosing the right combination for continued success. Finding predictable approaches for successful restorative procedures has been the goal of clinical and material scientists. This article provides a broad perspective on the advances made in various classes of dental restorative materials in terms of their functionality with respect to pit and fissure sealants, glass ionomers, and dental composites. PMID:21726695

  12. Dental and Chronological Ages as Determinants of Peak Growth Period and Its Relationship with Dental Calcification Stages

    PubMed Central

    Litsas, George; Lucchese, Alessandra

    2016-01-01

    Purpose: To investigate the relationship between dental, chronological, and cervical vertebral maturation growth in the peak growth period, as well as to study the association between the dental calcification phases and the skeletal maturity stages during the same growth period. Methods: Subjects were selected from orthodontic pre-treatment cohorts consisting of 420 subjects where 255 were identified and enrolled into the study, comprising 145 girls and 110 boys. The lateral cephalometric and panoramic radiographs were examined from the archives of the Department of Orthodontics, Aristotle University of Thessaloniki, Greece. Dental age was assessed according to the method of Demirjian, and skeletal maturation according to the Cervical Vertebral Maturation Method. Statistical elaboration included Spearman Brown formula, descriptive statistics, Pearson’s correlation coefficient and regression analysis, paired samples t-test, and Spearman’s rho correlation coefficient. Results: Chronological and dental age showed a high correlation for both gender(r =0.741 for boys, r = 0.770 for girls, p<0.001). The strongest correlation was for the CVM Stage IV for both males (r=0.554) and females (r=0.68). The lowest correlation was for the CVM Stage III in males (r=0.433, p<0.001) and for the CVM Stage II in females (r=0.393, p>0.001). The t-test revealed statistically significant differences between these variables (p<0.001) during the peak period. A statistically significant correlation (p<0.001) between tooth calcification and CVM stages was determined. The second molars showed the highest correlation with CVM stages (CVMS) (r= 0.65 for boys, r = 0.72 for girls). Conclusion: Dental age was more advanced than chronological for both boys and girls for all CVMS. During the peak period these differences were more pronounced. Moreover, all correlations between skeletal and dental stages were statistically significant. The second molars showed the highest correlation whereas the

  13. Proton Radiography Peers into Metal Solidification

    PubMed Central

    Clarke, Amy; Imhoff, Seth; Gibbs, Paul; Cooley, Jason; Morris, Christopher; Merrill, Frank; Hollander, Brian; Mariam, Fesseha; Ott, Thomas; Barker, Martha; Tucker, Tim; Lee, Wah-Keat; Fezzaa, Kamel; Deriy, Alex; Patterson, Brian; Clarke, Kester; Montalvo, Joel; Field, Robert; Thoma, Dan; Smith, James; Teter, David

    2013-01-01

    Historically, metals are cut up and polished to see the structure and to infer how processing influences the evolution. We can now peer into a metal during processing without destroying it using proton radiography. Understanding the link between processing and structure is important because structure profoundly affects the properties of engineering materials. Synchrotron x-ray radiography has enabled real-time glimpses into metal solidification. However, x-ray energies favor the examination of small volumes and low density metals. Here we use high energy proton radiography for the first time to image a large metal volume (>10,000 mm3) during melting and solidification. We also show complementary x-ray results from a small volume (<1 mm3), bridging four orders of magnitude. Real-time imaging will enable efficient process development and the control of structure evolution to make materials with intended properties; it will also permit the development of experimentally informed, predictive structure and process models. PMID:23779063

  14. Novel embossed radiography system utilizing energy subtraction

    NASA Astrophysics Data System (ADS)

    Osawa, Akihiro; Sato, Eiichi; Matsukiyo, Hiroshi; Enomoto, Toshiyuki; Watanabe, Manabu; Nagao, Jiro; Abderyim, Purkhet; Tanaka, Etsuro; Izumisawa, Mitsuru; Ogawa, Akira; Sato, Shigehiro

    2008-08-01

    Digital subtraction is useful for carrying out embossed radiography by shifting an x-ray source, and energy subtraction is an important technique for imaging target region by deleting unnecessary region in vivo. X-ray generator had a 100-μm-focus tube, energy subtraction was performed at tube voltages of 40 and 60 kV, and a 3.0-mm-thick aluminum filter was used to absorb low-photon-energy bremsstrahlung x-rays. Embossed radiography was achieved with cohesion imaging using a flat panel detector (FPD) with pixel sizes of 48×48 μm, and the shifting distance of the x-ray source in horizontal direction and the distance between the x-ray source and the FPD face were 5.0 mm and 1.0 m, respectively. At a tube voltage of 60 kV and a tube current of 0.50 mA, x-ray intensities without filtering and with filtering were 307 and 28.4 μGy/s, respectively, at 1.0 m from the source. In embossed radiography of non-living animals, the spatial resolution measured using a lead test chart was approximately 70 μm, and we observed embossed images of fine bones, soft tissues, and coronary arteries of approximately 100 μm.

  15. Proton Radiography Peers into Metal Solidification

    SciTech Connect

    Clarke, Amy J.; Imhoff, Seth D.; Gibbs, Paul J.; Cooley, Jason C.; Morris, Christopher; Merrill, Frank E.; Hollander, Brian J.; Mariam, Fesseha G.; Ott, Thomas J.; Barker, Martha R.; Tucker, Tim J.; Lee, Wah-Keat; Fezzaa, Kamel; Deriy, Alex; Patterson, Brian M.; Clarke, Kester D.; Montalvo, Joel D.; Field, Robert D.; Thoma, Dan J.; Smith, James L.; Teter, David F.

    2013-06-19

    Historically, metals are cut up and polished to see the structure and to infer how processing influences the evolution. We can now peer into a metal during processing without destroying it using proton radiography. Understanding the link between processing and structure is important because structure profoundly affects the properties of engineering materials. Synchrotron x-ray radiography has enabled real-time glimpses into metal solidification. However, x-ray energies favor the examination of small volumes and low density metals. In this study, we use high energy proton radiography for the first time to image a large metal volume (>10,000 mm3) during melting and solidification. We also show complementary x-ray results from a small volume (<1mm3), bridging four orders of magnitude. In conclusion, real-time imaging will enable efficient process development and the control of the structure evolution to make materials with intended properties; it will also permit the development of experimentally informed, predictive structure and process models.

  16. Proton Radiography Peers into Metal Solidification

    DOE PAGESBeta

    Clarke, Amy J.; Imhoff, Seth D.; Gibbs, Paul J.; Cooley, Jason C.; Morris, Christopher; Merrill, Frank E.; Hollander, Brian J.; Mariam, Fesseha G.; Ott, Thomas J.; Barker, Martha R.; et al

    2013-06-19

    Historically, metals are cut up and polished to see the structure and to infer how processing influences the evolution. We can now peer into a metal during processing without destroying it using proton radiography. Understanding the link between processing and structure is important because structure profoundly affects the properties of engineering materials. Synchrotron x-ray radiography has enabled real-time glimpses into metal solidification. However, x-ray energies favor the examination of small volumes and low density metals. In this study, we use high energy proton radiography for the first time to image a large metal volume (>10,000 mm3) during melting and solidification.more » We also show complementary x-ray results from a small volume (<1mm3), bridging four orders of magnitude. In conclusion, real-time imaging will enable efficient process development and the control of the structure evolution to make materials with intended properties; it will also permit the development of experimentally informed, predictive structure and process models.« less

  17. Emergency skull radiography: the effect of restrictive criteria on skull radiography and CT use

    SciTech Connect

    Baker, S.R.; Gaylord, G.M.; Lantos, G.; Tabaddor, K.; Gallagher, E.J.

    1985-08-01

    A prospective study was performed to determine the effect of restrictive criteria on the use of emergency skull radiography and computed tomography (CT) of the head. Emergency skull radiography required the completion of a special requisition form. Emergency CT of the head was done at the request of senior consultants and was available on a full-time basis. Over 1 year, 2758 skull studies were performed, a decrease of 39.1% when compared with the year before restrictive criteria were instituted, during which 4587 skull examinations were done. In the same period, the number of emergency CT scans of the head increased by 45.7%, from 471 in the control year to 686 in the experimental year. With the use of restrictive criteria, a net savings of $164,000 was achieved. Our results suggest that the use of restrictive criteria is a cost-effective means of limiting skull radiography when CT of the head is readily available.

  18. Recent developments in a CdTe-based x-ray detector for digital radiography

    NASA Astrophysics Data System (ADS)

    Glasser, Francis; Martin, Jean-Luc; Thevenin, Bernard; Schermesser, Patrick; Pantigny, Philippe; Laurent, Jean Yves; Rambaud, Philippe; Pitault, Bernard; Paltrier, Sylvain

    1997-05-01

    The performance of a new CdTe based x-ray detector devoted to digital radiography are presented. The detectors consist of a 6 cm2 CdTe 2D-array connected to CMOS readout circuit by indium bumps. The final image has 400 X 600 pixels with a 50 micron pitch. This solid-state detector presents the advantages of direct conversion, i.e. high stopping power with high spatial resolution and a significantly higher signal than commercially available scintillator/photodetector systems. The experimental results show excellent linearity, spatial resolution and detective quantum efficiency. The MTF was measured by the angled-slit method: 20 to 30 percent at 10 1p/mm depending on the incident x-ray energy. The measured DQE is about 0.8 at 40 KeV and 100 (mu) Gray dose. Our simulation shows that these experimental results do not reach the theoretical limit. Further improvements are in progress. The first industrial application will be dental radiography due to the small size and the excellent performances. We also tested the detector with x-rays form 20 KeV to 1.25 MeV. Of course the CdTe thickness should then be adapted to the incident x-ray energy.

  19. Accuracy of digital periapical radiography and cone-beam computed tomography in detecting external root resorption

    PubMed Central

    Geha, Hassem; Sankar, Vidya; Teixeira, Fabricio B.; McMahan, Clyde Alex; Noujeim, Marcel

    2015-01-01

    Purpose The purpose of this study was to evaluate and compare the efficacy of cone-beam computed tomography (CBCT) and digital intraoral radiography in diagnosing simulated small external root resorption cavities. Materials and Methods Cavities were drilled in 159 roots using a small spherical bur at different root levels and on all surfaces. The teeth were imaged both with intraoral digital radiography using image plates and with CBCT. Two sets of intraoral images were acquired per tooth: orthogonal (PA) which was the conventional periapical radiograph and mesioangulated (SET). Four readers were asked to rate their confidence level in detecting and locating the lesions. Receiver operating characteristic (ROC) analysis was performed to assess the accuracy of each modality in detecting the presence of lesions, the affected surface, and the affected level. Analysis of variation was used to compare the results and kappa analysis was used to evaluate interobserver agreement. Results A significant difference in the area under the ROC curves was found among the three modalities (P=0.0002), with CBCT (0.81) having a significantly higher value than PA (0.71) or SET (0.71). PA was slightly more accurate than SET, but the difference was not statistically significant. CBCT was also superior in locating the affected surface and level. Conclusion CBCT has already proven its superiority in detecting multiple dental conditions, and this study shows it to likewise be superior in detecting and locating incipient external root resorption. PMID:26389057

  20. Evaluation of panoramic digital images using Panoptiq for frozen section diagnosis

    PubMed Central

    Pradhan, Dinesh; Monaco, Sara E.; Parwani, Anil V.; Ahmed, Ishtiaque; Duboy, Jon; Pantanowitz, Liron

    2016-01-01

    Introduction: Whole slide imaging (WSI) permits intraoperative consultations (frozen sections) to be performed remotely. However, WSI files are large and can be problematic if there are tissue artifacts (e.g., tissue folds) or when slides are scanned without multiplanes (Z-stacks) to permit focusing. The Panoptiq dynamic imaging system allows users to create their own digital files that combine low power panoramic digital images with regions of interest that can be imaged using high power Z-stacks. The aim of this study was to determine the utility of the Panoptiq dynamic imaging system for frozen section telepathology. Materials and Methods: Twenty archival randomly selected genitourinary surgical pathology frozen sectional cases were evaluated using conventional light microscopy (glass slides), panoramic images, and whole slide images. To create panoramic images glass slides were digitized using a Prosilica GT camera (model GT1920C, Allied Vision Technologies) attached to an Olympus B × 45 microscope and Dell Precision Tower 810 computer (Dell). Panoptiq 3 version 3.1.2 software was used for image acquisition and Panoptiq View version 3.1.2 to view images (ViewsIQ, Richmond, BC, Canada). Image acquisition using Panoptiq software involved a pathology resident, who manually created digital maps (×4 objective) and then selected representative regions of interest to generate Z-stacks at higher magnification (×40 objective). Whole slide images were generated using an Aperio XT Scanscope (Leica) and viewed using ImageScope Software (Aperio ePathology, Leica). Three pathologists were asked to render diagnoses and rate image quality (1–10) and their diagnostic confidence (1–10) for each modality. Results: The diagnostic concordance with glass slides was 98.3% for panoramic images and 100% for WSI. Panoptiq images were comparable to the glass slide viewing experience in terms of image quality and diagnostic confidence. Complaints regarding WSI included poor focus