Panoramic Device Research Articles

Assessment of Diagnosis of Apical Root Fractures During Tooth Extraction Using Different Radiographic Techniques: An Ex-vivo Study

Objective: This study aimed to examine the diagnostic ability of different imaging techniques for apical root fractures that occur during tooth extraction by specialist dentists in different branches. Methods: Dry human mandibles used for education at Faculty of Dentistry and teeth extracted for routine treatment were used. After the root lengths were measured using a periodontal probe, the samples were adjusted to different lengths. These specimens were placed on a dry human mandible, and images were obtained and recorded using a periapical device, panoramic device, and computed tomography. Radiographs and recordings were performed by an oral and maxillofacial radiologist. The evaluation process was performed by an oral and maxillofacial radiologist, periodontologist, and oral and maxillofacial surgeon. Results: The diagnosis of 1 mm root presence and absence on periapical radiographs showed significant agreement among all observers. In the presence of 2 mm and 3 mm roots, all observers stated that the roots were present. On the panoramic radiographs, moderate agreement was observed in teeth with a 1 mm root. However, poor agreement between observers was observed for teeth with 2 mm and 3 mm roots. Cone-beam computed tomography (CBCT) was effective for the diagnosis of all observers. Conclusion: Consistent with the literature, the present study showed a higher interobserver agreement in CBCT. However, considering the patient's anxiety during the procedure, the duration of local anesthesia, and the surgeon's fatigue, two-dimensional radiographs are generally preferred over CBCT, which has a longer image processing time. Diagnosis using periapical radiographs was more effective than that using panoramic radiographs.

Determination of relative dose of ionizing radiation in the thyroid gland using a panoramic device with different protocols.

The use of panoramic radiography (PR) is a complementary examination to aid in the diagnosis of cases in paediatric dentistry. The lack of specific protocols for these devices, however, can result in high doses of radiation, affecting critical organs such as the thyroid. To evaluate the discrepancies in ionizing radiation received by the thyroid during PR examinations using anthropomorphic paediatric simulators built from computed tomography images. Two anthropomorphic paediatric phantoms were printed and used, representing children aged 6 and 11 years, with an opening in the thyroid region for the insertion of dosimetric radiographic films. The simulators were subjected to different pre-existing protocols in the PR devices. The radiographic films were processed and analysed using a luxmeter. The radiation dose to the thyroid was higher in the 6-year-old phantom than in the 11-year-old phantom, for given exposure factors. In addition, there was an increase in dose in children's protocols compared with small adult protocols. Therefore, companies that develop PR equipment must develop child protocols for separate age groups that will consequently reduce the radiation dose in children, especially in their critical organs.

Spot the Fire, Amuse the Alpinist. The Toposcope, an in situ Panoramic Device (1790–1910)

Initially designed at the end of the 18th century to identify the exact location of a fire during the dark hours of the night, the toposcope became in the following decades a tourist attraction device. Thanks most of all to the work of Alpine and Touring Clubs, the presence of these instruments spread throughout Europe under many names (Toposkop, Indicateur des Alpes, Table d’orientation). Alpine regions have been their crib, but they rapidly reached other environments. Wherever there was a good 360° vision of the surroundings, a toposcope could be placed. They constitute a universe that is as connected as varied. The deep time of their technology and their applicative variations also testify a migratory path which resembles many other panoramic devices. The article aims therefore to media-archaeologically trace the major dynamics of the toposcope. Not to uniform them under a homogeneous history, but to reflect upon its role in defining the modern meanings of mobility and virtuality. In that, the toposcope represents an interesting point of view since, unlike many other panoramic devices, it provides for an in situ mediated experience. Sharing some features with Augmented Reality, the toposcope elaborates a different approach to optical immersive experience.

All-embracing view

This pan.able initially anchors the user's attention in a portrait of a viewer, to reveal, progressively and successively, image display devices with contrasting purposes. Using the conceptual framework of the instrumental approach (Rabardel 1995) seems to us to be heuristic, in order to bring out the instrumented activity of the gaze, which is situated in different times and places. Shaping the problematic of our research through a visual approach is not to close the analysis but to accompany the genesis of the views in the process of being made. Indeed, if the user first discovers a portrait of a viewer, the questions on either side of the portrait invites them to navigate either towards the object of this viewer's activity (“What is she contemplating?”), or toward the instrumentation of her gaze (“How does she look at what she is looking at?”). Questions guide the user in the different aspects of the conceptual model, which constitutes the core of the instrumental approach: the instrument (the image display device), the subject (the Viewer) and the object of the activity (Faux Terrain) The successive questions allow the user to browse within two photographic series by Arno Gisinger (Betrachterbilder and Faux Terrain) to address the question of the gaze's formatting through the intermediary of a panoramic device of the end of the 19th century, that of the battle of Bergisel in Innsbruck. As a counterpoint to the panorama that conditions the gaze, the user is then invited to discover this double series (Betrachterbilder and Faux Terrain) exhibited opposite each other in Frankfurt's Schirn Kunsthalle, in a scenography that encourages the emancipation of the gaze. Indeed, according to their own path and their own singular logic, each visitor can rearrange the images shown in the rotunda. Through this gesture within this pan.able, combining photographic and conceptual prisms, reiterated in a variety of contexts, we invite .able users to become progressively aware of the framework of their gaze by making visible image display devices through graphic representations. When there is a genesis of the gaze, the gaze initially stumbles, and is prevented from seeing as usual. Then, if, and only if, the experience is opened up, the world being viewed, and the viewer, are both transformed in the interweaving of the gaze. It is by wandering through the staging of successive re-creations of Arno Gisinger's photographic and scenographic work that viewers of the .able journal come into contact with the experiential depth of their own gaze. It is thus the successive reworkings that give shape to the experience of the gaze, which settles in a superimposition, an accumulation of worlds like nesting dolls. This mise en abyme is extended in the reflexive gesture of inviting .able's viewers to look back on their own gaze within the pan.able. The aim of this visual publication is to open a research-creation program titled “genesis of gazes,” at the crossroads of ergonomics, photography, and education.

Design of a Panoramic Scanning Device Based on a Piezoelectric Ceramic Stack Actuator and Friction Transmission

In view of the complex structure and inaccurate positioning capabilities of the existing panoramic scanning system, a panoramic scanning device based on a piezoelectric ceramic stack actuator and friction transmission was designed. In our model, the output displacement of the piezoelectric ceramics is amplified by a bridge-type flexure hinge and applied to a shaft by friction to achieve panoramic scanning imaging. The mathematical model of the device was established, and the working characteristics were analyzed. The analysis demonstrated that the linear displacement increment of the shaft is a superposition. A modality simulation was performed, and the simulation results show that the designed device works normally at a frequency of 511.5 Hz. The test results indicated that the displacement of the actuator can reach 6 μm at an input voltage of 100 V. Moreover, the laser scanning results showed that the designed device can perform panoramic scanning imaging, which meets the requirements for use on the high-speed imaging system.

Binerization of Panoramic Dental Image for Dental Anatomy Identification

Dental image is used for identification of a person because it can provide a lot of information about dental such as tooth contour, tooth position, and tooth shape. This research aims to process dental panoramic images in the form of greyscale images into binary images. Converting the greyscale image to binary is known as the thresholding process. The thresholding process is also called binerization. The input data used in this study is in the form of dental anatomical images produced by dental panoramic devices. The data used were 20 images, namely 10 abnormal dental images and 10 normal dental images. Results for the identification of dental anatomy with binerization the system and the manual calculation are the same. Identification normal dental are 50% and abnormal dental are 80%.

Awareness and practice of 2D and 3D diagnostic imaging among dentists in Hong Kong.

Aims To investigate the awareness and practice of 2D and 3D diagnostic imaging, including respective equipment, specifications, number of images acquired, indications for CBCT scans, preference between 2D and 3D imaging, and the confidence in acquiring and interpreting radiographic images among dentists in Hong Kong.Materials and methods A citywide survey was performed with an online questionnaire that was sent via the local dental association to registered dentists in Hong Kong. The anonymous survey focused on: their dental background; number, type and age of their intra-oral, panoramic devices; CBCT indications, field-of-view and consideration of low-dose protocols; and their confidence in taking and interpreting these images.Results From the feedback collected, 65% of dentists used digital intra-oral systems. Around 70% of respondents who perform CBCTs utilised low-dose protocols to reduce radiation dose. Age and years of practising dentistry were significant influencing factors in determining dentists' utilisation of low-dose protocols for CBCT devices. Male dentists and dentists with higher qualifications generally reported being more confident in taking and interpreting CBCT images. Dentists who were older and had more years of practising dentistry were generally more confident in interpreting CBCT images.Conclusion Only half of the dentists feel confident in taking and interpreting CBCT images, and there seems to be a limited knowledge of radiation dose-related risks. Therefore, continuous professional education should specifically focus on the potential of digital imaging and training in CBCT modalities, radiation dose protection and image interpretation.

Measuring the dose-width product and proposing the local diagnostic reference level in panoramic dental radiography: a multi-center study from Iran.

Although radiation exposure associated with dental radiography is relatively low, patient exposure must be kept practically low. Therefore, it is necessary for each country to establish its own diagnostic reference levels (DRLs) suitable for its equipment and practice. In the present study, dose-width product (DWP) values for panoramic dental radiography were measured and a local DRL was established. Five panoramic devices from five radiology clinics of Kashan, Iran were selected to measure the DWP values of panoramic dental radiography. To investigate the DWP values, the parameters of each patient's exposure (e.g., tube voltage, tube current, and exposure time) at these five radiology clinics were extracted. Then, the dose value received by each patient was measured based on a CT pencil chamber. Finally, the overall median DWP values for the patients with small, medium, and large sizes were obtained, and these values were considered as the local DRLs for panoramic dental radiography. A total of 99 adult patients were included in the present study. The findings demonstrated that the median and third-quartile DWP values for these five radiology clinics ranged from 42.3 to 94.3 and 49.7 to 142.8mGymm, respectively. The local DRL values, which were established as the overall median DWP values, were 43.4, 52.0, and 80.3mGy mm for the adults with small, medium, and large sizes, respectively. The local DRL proposed in this study for the adult with standard/medium size was lower than those proposed by other reports and seemed acceptable for panoramic radiography in Kashan, Iran.

Entrance skin dose of the thyroid gland area following exposure with different protocols of two panoramic and cone-beam computed tomography devices

Background: Cone-beam computed tomography (CBCT) has gained considerable use, while radiation burden remains an important concern. Aims: This study aimed at determining the entrance skin dose of the thyroid gland area through exposure with the normal, soft, and hard modes of Vatech (Pax-i) panoramic device as well as different field of views (FOVs) of Vatech (Pax-i 3D) CBCT system. Materials and Methods: Dose measurements were performed on a head-and-neck phantom by an ion chamber dosimeter. Panoramic imaging was done in three normal, soft, and hard modes, each entailing woman, man, and child options. CBCT examinations were performed with various FOVs, each having normal, soft, and hard modes as well as woman, man, and child choices. Doses obtained from different protocols of the two imaging modalities were compared by paired t-test. Results: All FOVs in CBCT resulted in greater radiation dose than panoramic in each of the normal, soft, and hard exposure modes (P

Panoramic shot device of 720‐degree VR for hexacopter UAV based on three‐axis gimbal

A new structure and an improved control method of the three-axis gimbal for hexacopter unmanned aerial vehicle (UAV) are presented. By optimising the structure of the three-axis gimbal and establishing the mathematical model with the maximum stability, the improved structure of three-axis gimbal is proposed, which two groups of virtual reality (VR) camera arrays are mounted on the top and bottom of the frame to meet requirements of the 720-degree panoramic shot. The redundant design of five motors in the structure could realise the stabilisation of three-axis linkage of the gimbal that will ensure the optimal performance of the independent stable cameras all the time. At the same time, the attitude of the gimbal could be controlled by the complementary filter and proportional, integral and derivative algorithms. Furthermore, the closed-loop controls of angle, speed and current of Brushless DC motor are realised by the non-contact magnetic encoder, which improves the anti-shake performance of the system. The experiments in the prototype are designed to prove the anti-shake performance of the proposed gimbal and stability of the hexacopter UAV.

Comparative Study of the Effective Dose from Panoramic Radiography in Dentistry Measured Using a Radiophotoluminescent Glass Dosimeter and an Optically Stimulated Luminescence Detector

Accurate measurement of the absorbed dose and the effective dose is required in dental panoramic radiography involving relatively low energy with a rotational X-ray tube system using long exposures. To determine the effectiveness of measuring the irradiation by using passive dosimetry, we compared the entrance skin doses by using a radiophotoluminescent glass dosimeter (RPL) and an optically stimulated luminescence detector (OSL) in a phantom model consisting of nine and 31 transverse sections. The parameters of the panoramic device were set to 80 kV, 4 mA, and 12 s in the standard program mode. The X-ray spectrum was applied in the same manner as the panoramic dose by using the SpekCalc Software. The results indicated a mass attenuation coefficient of 0.008226 cm2/g, and an effective energy of 34 keV. The equivalent dose between the RPL and the OSL was calculated based on a product of the absorbed doses. The density of the aluminum attenuators was 2.699 g/cm3. During the panoramic examination, tissue absorption doses with regard to the RPL were a surface dose of 75.33 μGy and a depth dose of 71.77 μGy, those with regard to the OSL were surface dose of 9.2 μGy a depth dose of 70.39 μGy and a mean dose of 74.79 μGy. The effective dose based on the International Commission on Radiological Protection Publication 103 tissue weighting factor for the RPL were 0.742 μSv, 8.9 μSv, 2.96 μSv and those for the OSL were 0.754 μSv, 9.05 μSv, and 3.018 μSv in the parotid and sublingual glands, orbit, and thyroid gland, respectively. The RPL was more effective than the OSL for measuring the absorbed radiation dose in low-energy systems with a rotational X-ray tube.

Accuracy of digital panoramic radiographs on the vertical measurements of dental implants

Objectives: Panoramic radiography (PR) is the most commonly used technique to evaluate the dental and associated structures. The aim of this study was to determine the accuracy of panoramic radiographs (PRDs) in planning of dental implant treatment and the magnification rate of a panoramic device for anterior, premolar and posterior regions.Materials and Methods: Eighty-eight patients, who received PRD after implant surgery, were included to the study. A total of 240 dental implants (53 anterior, 69 premolar, and 118 molar regions) of which previously vertical lengths were known, were re-measured on post-operative radiographic images using the scaling tools of the panoramic system to determine the magnification rate and the accuracy of PRDs. Cause the data had normal distribution, the paired t test was used for the statistical analysis (p<0.05). The magnification rate of the three regions was calculated as the rate of measured vertical length of the implants to the actual vertical length of the implants. Results: Statistically significant difference was found between the actual and measured vertical length of the implants on the PRD (p<0.05). However, the correlation rate was found close to 1 for all regions. The difference between the actual and measured vertical length of the implants on the PRD was 0.50 mm for the anterior region, 0.97 mm for the premolar region, and 0.83 mm for the molar region. The magnification rate of the panoramic system corrected by CliniviewTM (Instrumentarium Corp., Tuusula, FINLAND) software was found around 1 for all the regions. Conclusions: Due to their readily accessible nature and low radiation dose, PRDs can be used in implant surgery for vertical measurements with 1 mm confidence interval.

RADIATION DOSE FROM DENTAL RADIOGRAPHY IN INDONESIA: A FIVE-YEAR SURVEY.

Dose metrics on intraoral and panoramic dental radiography were analyzed to preliminarily indicate dose trend of dental radiology equipment in Indonesia. Measurements were performed in 71 healthcare institutions involving a total of 92 dental X-ray devices. Imaging modes are categorized into 'low dose' and 'high dose' based on the task. The 75th percentile for intraoral IAK was 2.8 and 4.3 mGy for 'low' and 'high' dose modes, respectively while for panoramic devices the 75th percentile of the KAP for 'low' and 'high' dose modes were 85.2 and 192.4 mGy cm2, respectively. Results compared with local regulatory recommendation for intraoral units indicated that 38.8 and 6.3% of measured dose modes on analogue and digital devices, respectively, were above the recommended range. The dose trend can be used as reference for local regulations concerning patient dose in dental radiography and preliminary value prior to the establishment of national diagnostic reference level.

Absorbed doses in salivary and thyroid glands from panoramic radiography and cone beam computed tomography

Abstract Introduction: Panoramic radiography and cone beam computed tomography (CBCT) are very important in the diagnosis of oral diseases, however patients are exposed to the risk of ionizing radiation. This paper describes our study aimed at comparing absorbed doses in the salivary glands and thyroid due to panoramic radiography and CBCT and estimating radiation induced cancer risk associated with those methods. Methods Absorbed doses of two CBCT equipment (i-CAT® Next Generation and SCANORA® 3D) and a digital panoramic device (ORTHOPANTOMOGRAPH® OP200D) were measured using thermoluminescent dosimeters loaded in an anthropomorphic phantom on sublingual, submandibular, parotid and thyroid glands. Results Absorbed doses in the i-CAT® device ranged between 0.02 (+/-0.01) and 2.23 mGy (+/-0.03), in the SCANORA™ device ranged from 0.01 (+/-0.01) to 2.96 mGy (+/-0.29) and in the ORTHOPANTOMOGRAPH® OP200D ranged between 0.04 mGy and 0.78 mGy. The radiation induced cancer risk was highlighted in the salivary glands, which received higher doses. The protocols that offer the highest risk of cancer are the high resolution protocols of CBCT equipment. Conclusion CBCT exposes patients to higher levels of radiation than panoramic radiography, so the risks and benefits of each method should be considered. The doses in CBCT were dependent on equipment and exposure parameters, therefore adequate selection minimizes the radiation dose.

The Effect of Changing Focal Trough in a Panoramic Device on the Accuracy of Distance Measurements

Introduction: Magnification and distortion are the most important limitations of panoramic radiography. The aim of this study was to determine the effects of changing focal trough option of Planmeca SCARA 3 on the accuracy of linear distance measurements. Materials and Methods: In this in-vitro study, 28 pieces of gutta-percha were attached to the assumptive place of each lost root of an adult dry skull with average size and normal shape. The actual measurements were obtained by a digital caliper. The panoramic images of the skull were taken in six different sizes and shapes of focal trough. This procedure was repeated ten times with new gutta-percha. Paired t-test was used to compare the values of different actual and radiographic images of gutta-percha dimensions. Results: The mean difference [standard deviation (SD)] between actual measurement and panoramic radiography in the different groups was from 0.37 (1.1) to 0.58 (2.87) mm. The mean (SD) difference of linear measurements between real and radiographic images was 0.52 (0.43) mm in average size, V-shaped group, which was statistically and clinically significant (P = 0.00). Conclusion: Changing the focal trough option of Planmeca SCARA 3 has minimal effects on the accuracy of linear measurements in panoramic radiographs.

Feasibility of dental panoramic radiography for dental arch evaluation in small animals

The purpose of this study was to evaluate the feasibility of dental panoramic radiography for dental arch evaluation in small animals. The dental arches of four Beagles, one Shih Tzu dog, and three Korean short-haired cats were radiographed using human panoramic X-rays. All animals were under general anaesthesia during the examination. The animals’ heads were placed horizontal to the panoramic device, just as a human’s head is placed in panoramic dental assessments. All animals were evaluated with an open and closed mouth view (human view). In the closed mouth view, the animal was provided a bite blocker for proper placement of the oral cavity. The open mouth view angle was approximately 30–45°. The maxilla and mandible were held in position with radiolucent 3M tape. The standard scoring measurement was performed based on visibility of the tooth root and the sharpness of the dento-alveolar margin. No significant differences in scoring were noticed between the two positions. The visibility of teeth roots in Beagles was far better than that in the Shih Tzu dogs and two Korean short-haired cats. In addition, the Beagle series showed sharp dento-alveolar margin scores. These results suggest that human panoramic dental X-rays represent a possible dental evaluation tool for animals with large skulls.

Assessment of panoral radiograph quality in a dental treatment center

Purpose The quality of orthopantogram (OPG) images is primarily a function of patient positioning during image capture. The purpose of the investigation was to evaluate the quality of digital panoral radiographic images obtained by using the same imaging device in a large dental treatment center on the basis of the radiography technician operator securing the image. Materials and Methods Three hundred OPGs radiographs taken on a Kodak 8000C Digital Panoramic and Cephalometric System device in a large dental treatment center comprised the sample. The most recent OPGs beginning at May 2010 through 2007 were selected for three radiography technicians until subgroups of 100 OPGs per technician were obtained. Each panoral was evaluated by two investigators for 21 OPG image errors. Results Mean panoral total score was 14.71 and mean grade was 2.41 for the entire sample indicating a “good” quality. Significant differences were found among technicians for 3 of 21 panoral fault variables. The relative contribution to inferior OPG quality was greatest for the following positioning faults in rank order: Gazebo effect (11.3%), condyles pushed out (11.0%), unclear nasal structures (10.0%), airspace over U6s (9.5%), and condyles image top (9.0%). Conclusions There were no significant differences among technicians for overall quality indicators (total score and grade). However, statistically significant differences among the three technicians were found for image error wide anterior teeth, Gazebo effect, and unclear nasal structures.

The cadmium telluride photon counting sensor in panoramic radiology: gray value separation and its potential application for bone density evaluation

To investigate whether bone mineral density can be evaluated more accurately using a panoramic device with a new cadmium telluride photon-counting sensor and software than 2 panoramic devices with a conventional semiconductor sensor. A fiduciary test object with several known levels of hydroxy apatite mineral concentration was placed in a phantom on the mandibular occlusal plane. Panoramic images were acquired by changing the position of the test object within the dental arch. The gray value, the spectrum deformation index (SDI), and the relative attenuation index (RAI) of the test object were evaluated. The SDI and RAI represent unique energy information as acquired by the QR-Master panoramic machine and the corresponding special QR-MC analysis software. In order to compare the values expressed in the different units (gray, SDI, and RAI values), the percentage discrepancy was calculated. The cadmium telluride photon-counting fitted machine more consistently separated each of the hydroxy apatite concentrations in all of the different positioning configurations and locations. The SDI function of the QR Master machine produced more stable values than the RAI value and the gray values of the 2 conventional panoramic machines. The methodologies as developed for this study can be used to test more sophisticated analyses for the determination of bone density.

PTH-185 Mapping the gastric mucosal surface: image mosaicking for capsule endoscopy

Introduction Upper gastrointestinal (GI) endoscopy is invasive, incurs risks and most findings are not relevant to the symptoms. Yet 1% of the population undergo upper GI endoscopy per annum and the Be Clear on Cancer campaign expects a 52% increase in demand. Several studies suggest that capsule endoscopy (CE) could be used to examine the upper GI tract, but lack of control and difficulties locating landmarks could increase the chance of missed pathology. We aimed to see if it were possible to map the gastric mucosal surface using mosaicking algorithms to stitch together overlapping CE video frames: a technique which could be used to inform clinicians about completeness of examination. Method An algorithm for image mosaicking from CE video frames was developed based on the feature selection method SURF (speeded up robust features). This ’blob detection’ method recognises local regions of an image which are distinguishable by properties such as brightness and matches them in overlapping images. SURF is fast to compute, adapts to variations in rotation and scale and therefore is potentially suitable for analysing CE images. In order to establish that there were enough features for image stitching in the CE images we performed a control test: a single CE image from a forward viewing Mirocam Navi (Intromedic, Seoul, South Korea) was divided up into overlapping subsections. Each subsection was separately submitted to a random transformation of scaling, rotation and translation. These images were then given as an input sequence to the algorithm in order to be stitched back together. A further test of the image stitching algorithm was performed using the Capsocam (Capsovision, CA, USA) capsule, which incorporates four 90° side viewing cameras and is therefore advantageous for mapping because of its 360 O panoramic view. Results Using control images from human stomachs we established that there are sufficient features in gastric CE images to allow feature based image mosaicking. This applied to imaging obtained both from both forward viewing and panoramic view devices. Finally, we found that the success of the image mosaicking depended on the movement of the capsule, and whether there were sufficient overlapping features from frame-to-frame for stitching images together. Conclusion Our data show that there are sufficient features to stitch together CE video frames confirming the possibility of developing gastric surface mapping using image mosaicking techniques. A degree of control may be necessary in order to achieve a ‘slow sweep’ over the mucosal surface in order to maximise the acquisition of overlapping features. Disclosure of interest None Declared.

Are the makings of a dirty bomb in your neighborhood?

Although regulators say that current protections are adequate, the US government continues to pay for extra security features for facilities that hold radiological materials.