scholarly journals Accuracy of measurements performed on digital panoramic radiographs with and without an extra-oral calibration object

St open ◽  
2020 ◽  
Vol 1 ◽  
pp. 1-11
Author(s):  
Frane Mihanović ◽  
Anita Ivanović
Keyword(s):  
Vertical Direction ◽  
Panoramic Radiograph ◽  
Horizontal Direction ◽  
Dicom Image ◽  
Mean Values ◽  
Panoramic Radiographs ◽  
Accuracy Of Measurements ◽  
Clinical Accuracy ◽  
Calibration Object ◽  
Image Format

Aim: To investigate the accuracy of measurements in vertical and horizontal direction using an extra-oral calibration object placed in different positions on the panoramic radiograph in JPEG and DICOM image format. Methods: Digital panoramic radiographs of a purpose made model with 32 removable teeth replaced with metal balls were taken. The measurements of metal balls were performed with and without the calibration object placed in the middle or on the side of the radiograph in JPEG and DICOM image formats. Results: One sample t-test was used for the analyses of accuracy of measurements in vertical and horizontal direction. The most accurate vertical measurements were achieved in canine group in JPEG (6.02±0.04 mm, P=0.144) and DICOM (6.03±0.07 mm, P=0.104) formats using calibration object placed in the middle of the radiograph. The mean values of measurements in horizontal direction differed significantly from the real values (P<0.05) in all teeth groups regardless of the image format. Conclusion: The most accurate measurements in vertical direction were achieved by placing the metal scale ruler extra-orally in the middle of panoramic radiograph independent of the image format. Reliable clinical accuracy for measurements in horizontal direction was achieved only in canine region (G2) in both image formats.

Panoramic radiographs

2005 ◽  
Vol 29 (2) ◽  
pp. 165-166 ◽  
Author(s):  
Elham S.J. Abu Alhaija
Keyword(s):  
Panoramic Radiograph ◽  
Growth Direction ◽  
Mean Values ◽  
Mandibular Growth ◽  
Panoramic Radiographs ◽  
Gonial Angle ◽  
Dental Examination ◽  
The Mean ◽  
Dental Professional ◽  
Distal Border

The aim of this study was to evaluate the potential of panoramic radiographs to measure mandibular inclination and steepness. Standardized panoramic and lateral cephalometric radiographs were taken for 95 subjects (46 females, mean age 12.4 ± 1.2 years; 49 males, mean age 12.1 ± 1.3 years). Mandibular inclination from panoramic radiograph was measured using gonial angle formed by the tangents of the lower border of the mandible and the distal border of the ascending ramus and the condyle. A correlation test was performed to check for similarity between the measurements. The mean values for the gonial angle were 127.3 ± 6.2 and 125.7 ± 6.5 degrees measured from the panoramic and cephalometric radiographs respectively. A high correlation between the measurements taken from both radiographs was found (r=0.83, P<0.001). Panoramic radiographs are a useful tool for the measurement of gonial angle, which is an indicator of manibular steepness and subsequently mandibular growth direction. The ability to determine growth direction from the orthopantomogram will be useful because majority of dentists request an OPG for patients during routine dental examination. This will enable the dental professional to spot vertical growth problems using a readily available tool. J Clin Pediatr Dent 29(2): 165-166,2005

EVALUATION OF OCCURRENCE OF HYPERDONTIA IN NON-SYNDROMIC POPULATION FROM BIHAR REGION

2019 ◽  
Vol 3 (10) ◽  
Author(s):  
Dr. Minti Kumari ◽  
Dr. Madhuri Kumari ◽  
Dr Anurag Rai ◽  
Dr. Navin Kumar
Keyword(s):  
Panoramic Radiograph ◽  
Permanent Dentition ◽  
Dental Anomalies ◽  
Supernumerary Teeth ◽  
Panoramic Radiographs ◽  
Future Studies ◽  
Asian Populations ◽  
Males And Females ◽  
The Individual ◽  
Clinical Records

It is evident that hyperdontia is more common in the permanent dentition than in the primary. There is a considerable difference between males and females in the prevalence of these teeth in permanent dentition; hyperdontia is twice as common in males as in females. However, this approximation varies in terms of location, other associating syndromes that may be present, and the ethnicity of the individual. In terms of ethnicity, it can be seen that hyperdontia is in fact less common in Caucasian than in Asian populations. There is evidence to show that an individual is more likely to have hyperdontia if other members of their family also have the condition. Hence the present study was planned for evaluation of occurrence of hyperdontia in non-syndromic  population from Bihar Region. The present study was planned in Public Health Dentistry, Patna Dental College and Hospital, Patna, Bihar. Total 195 patients referred to Department of Dentistry were evaluated in the present study. Panoramic radiographs and clinical records of patients above the age of 18 years and without any syndromic features were selected for the study.  All the radiographs were examined for the presence of supernumerary teeth, their location, morphology, and number. Morphologically, teeth were classified as conical, tuberculate, supplemental, and odontoma. Early diagnosis of dental anomalies can prevent some esthetic, orthodontic, and periodontal problems, and knowledge of the prevalence and distribution of the anomalies may help clinicians to the detection of these anomalies at early stages. Our study evaluated the prevalence of selected dental anomalies; future studies should investigate the prevalence of dental anomalies of all types. Keywords: Hyperdontia, non-syndromic, panoramic radiograph, supernumerary teeth, etc.

scholarly journals Styloid process elongation and calcification in subjects with tmd: clinical and radiographic aspects

2012 ◽  
Vol 23 (4) ◽  
pp. 443-450 ◽  
Author(s):  
Kelly Machado de Andrade ◽  
Carolina Almeida Rodrigues ◽  
Plauto C. Aranha Watanabe ◽  
Marcelo Oliveira Mazzetto
Keyword(s):  
Orofacial Pain ◽  
Panoramic Radiograph ◽  
Styloid Process ◽  
Eagle’S Syndrome ◽  
Linear Measurements ◽  
Panoramic Radiographs ◽  
Elongated Styloid Process ◽  
Cephalometric Radiograph ◽  
Lateral Cephalometric Radiograph ◽  
Process Length

Knowledge of the Eagle's syndrome shows that its symptoms can be very easily confused with other types of craniomandibular disorders, especially temporomandibular disorders (TMD). The aim of this study was to find a possible correlation between the presence of TMD and elongation of the styloid process as well relate to presence of calcification of the stilohyoid chain. Fifty patients with TMD, confirmed from the RDC/TMD, were examined clinically and radiographically. Radiographic documentation consisted of digital panoramic radiograph and digital lateral cephalometric radiograph. Radiocef software (Radiomemory) was used for the analysis of radiographs by means of specific cephalometric tracing and linear measurements of the styloid process. Each radiograph was traced and measured three times with intervals of 1 month to spread the error. Statistical analysis was performed by Pearson's test (p=0.001) using Biostat 4.0 statistical software. Result showed an incidence of 76% elongation of the styloid process in the sample. There was a correlation between the bilateral measures taken in panoramic radiographs (?<0.001) and also for measures of styloid process length carried out in different panoramic radiographs and lateral cephalometric radiographs (?<0.001). It was concluded that there is prevalence of elongated styloid process in patients with TMD. However, no relationship was found between measurements on the stylohyoid chain and symptoms of headache, orofacial pain, tinnitus and vertigo.

Spontaneous Blinks as a Criterion of Visual Fatigue during Prolonged Work on Visual Display Terminals

2001 ◽  
Vol 92 (1) ◽  
pp. 234-250 ◽  
Author(s):  
Kenichi Kaneko ◽  
Kazuyoshi Sakamoto
Keyword(s):  
Time Lag ◽  
Vertical Direction ◽  
Visual Display ◽  
Hard Copy ◽  
Subjective Feeling ◽  
Visual Fatigue ◽  
Work Time ◽  
Mean Values ◽  
Significant Difference ◽  
The Mean

Visual fatigue caused by prolonged work viewing a Visual Display Terminals (VDT) and of work reading a hard-copy were assessed by electromyogram (EMG) waveform and electrooculogram (EOG) waveform in spontaneous blinks as objective criteria, and by questionnaire of subjective feeling, and by task performance. The duration and the amplitude of the EMG of the orbicularis ocular muscle on the right side and the EOG of the vertical direction to the eyelid were measured for 10 subjects who participated in a figure task consisting of the addition of single-digit numbers on a VDT work or a work with a hard-copy. The mean values of the duration and the amplitude of the EMG and the EOG were evaluated by the averaging of 10 waveforms of the spontaneous blinks for all subjects. The time lag from the EMG to the EOG in the process of the generation of spontaneous blinks was also analyzed. These five parameters were evaluated during the work time. The mean values for the duration of the EMG increased gradually during the work time, but the amplitude did not show significant difference between the prework and a work time. There was no significant change of the duration of the EOG, but the mean amplitude of the EOG decreased as the work time progressed, and the time lag significantly extended. The blinks frequency increased relatively when using a VDT. The rate of fluctuation for these parameters was higher during use of a VDT than use of a hard-copy. The time lag at five hours of VDT work was extended by 90% based on the value at the prework. The symptoms of general fatigue and fatigue of the eyes increased linearly during the VDT work for six hours. The results indicated a significant correlation between the objective parameters for the activity of the spontaneous blinks, i.e., duration and amplitude of EMG and EOG, and the time lag between EMG and EOG, and the subjective feeling was recognized in the time course of the task. These experimental results suggested that the parameters regarding the EMG and the EOG for the spontaneous blinks were effective indices for assessing visual fatigue during prolonged VDT work.

Numerical Simulation of a Jumper Conveying Slurry for Deep-Sea Mining

2021 ◽  
Author(s):  
Marcio Yamamoto ◽  
Tomo Fujiwara ◽  
Joji Yamamoto ◽  
Sotaro Masanobu
Keyword(s):  
Experimental Data ◽  
Pressure Drop ◽  
Dynamic Analysis ◽  
Internal Pressure ◽  
Deep Sea ◽  
Petroleum Industry ◽  
Vertical Direction ◽  
Internal Flow ◽  
Horizontal Direction ◽  
Viscous Pressure

Abstract One key technology for Deep-Sea Mining is the riser system. The riser is already a field-proven technology in the Petroleum Industry. However, several differences exist between a petroleum production riser and a riser for Deep-Sea Mining, mainly related to the internal flow. The ore-slurry has a larger density than the hydrocarbons and shall be pumped with a much higher flowrate. The current software tools for riser’s dynamic analysis may include the internal fluid hydrostatic pressure and the centrifugal and Coriolis forces imposed by the bent pipe’s internal flow. However, the internal pressure drop is not calculated. The internal pressure alters the pipe’s effective tension and can alter the pipe’s bending moment changing its mechanical behavior. This article describes a computational script’s development to run embedded in a commercial software for riser’s dynamic analysis. Our script calculates the internal viscous pressure drop along with the jumper. This pressure is then converted into wall axial tension (buckling) and imposed on each node of the jumper’s numerical model. Each simulation case was calculated twice with and without the internal flow viscous pressure drop. The comparison with experimental data revealed that the jumper’s average position has a good agreement among all cases. However, the amplitude caused by the top oscillation showed some discrepancies. Experimental data has the highest amplitude in the horizontal direction, while the simulation without viscous pressure calculation had the smallest. The simulation with our embedded script had intermediary amplitude in the horizontal direction. The vertical direction amplitudes have the same behavior for all cases, but the experimental data showed the highest amplitude.

scholarly journals Optimal Use of a Panoramic Radiograph as a Screening Tool for Condylar Resorption in Patients Undergoing Active Orthodontic Treatment: A Case Series

2020 ◽  
Vol 10 ◽  
pp. 65
Author(s):  
Shaima Malik ◽  
Shilpa Singh ◽  
Robby T. George ◽  
Mayank Kakkar ◽  
Nikhilesh R. Vaid
Keyword(s):  
Orthodontic Treatment ◽  
Behavioral Therapy ◽  
Mandibular Condyle ◽  
Case Series ◽  
Panoramic Radiograph ◽  
Degenerative Joint Disease ◽  
Joint Disease ◽  
Initial Examination ◽  
Panoramic Radiographs ◽  
Specific Medication

Condylar resorption of temporomandibular joint findings in the panoramic radiographs is an indication of bone resorption suggesting possible degenerative joint disease that warrants early screen and subsequent referral to a dedicated specialist. This case series reports three patients that underwent the active orthodontic treatment for the duration of approximately 24–36 months. The patients were asymptomatic at the initial examination. The clinical examination was negative for clicking; the range of motion on opening, lateral excursion, and protrusion was normal. Neither of these patients had a history of rheumatic disease or bruxism. During the later stages of orthodontic treatment, two of the three patients reported mild pain and clicking during mastication, which was also confirmed chairside on clinical evaluation. Patients were referred to the orofacial pain specialist, were they were prescribed specific medication for the symptoms, along with cognitive behavioral therapy, and were further evaluated for splint therapy. Panoramic radiographs taken before the start of the treatment, during the treatment and at the completion of the orthodontic treatments indicate the progression in the resorption of mandibular condyle in all three patients suggesting possible degeneration that warrants further investigation and therapy.

Grief and the Imminent Threat of Non-Being

1971 ◽  
Vol 118 (545) ◽  
pp. 467-468 ◽  
Author(s):  
S. Sunder Das
Keyword(s):  
Vertical Direction ◽  
Horizontal Direction ◽  
Self Awareness ◽  
Differentiated Integration ◽  
Existential Grief ◽  
The Subject ◽  
Cultural Dominance ◽  
Imminent Threat

The experience and meaning of grief differs with the progression of self-awareness of the experiencer in his ontogenetic evolution from utter dependence to differentiated integration. Autonomy, achieved by very few adults, carries with it the connotation of transcendence over mere obedience and conformity to the canons of society. This is different from deviance in two important respects. Deviance is a movement in a horizontal direction away from cultural dominance, and therefore could manifest itself in antisocial activities. Autonomy, being a movement in a vertical direction, is supra-cultural and non-conformist rather than antisocial. All this has a great deal to do with existential grief, the experience of which can change according to the level of ontology of the experiencer. The following operational definitions are needed to treat the subject of ontological grief in a meaningful manner.

Design and Application of the Butt Auxiliary Device for the Erection of Steel Tower Using Helicopter

2013 ◽  
Vol 387 ◽  
pp. 319-322
Author(s):  
Yong Jun Xia ◽  
Qian Miao ◽  
Ke Xin Huang
Keyword(s):  
Transmission Line ◽  
Simple Structure ◽  
Engineering Application ◽  
Vertical Direction ◽  
Horizontal Direction ◽  
Construction Technology ◽  
Overhead Transmission Line ◽  
Auxiliary Device ◽  
Design And Application

The erection construction technology of steel tower of overhead transmission line using helicopter has higher requirements to the butt auxiliary device. According to the GE1 steel tower of the QingZang AC/DC interconnection project Geermu converter station earthling line, the butt auxiliary device is developed. The butt auxiliary device includes a guiding device, horizontal-direction caging device and vertical-direction caging device and solve the problems as follows limiting in air, docking, perching and temporary supporting. The successful engineering application show that the butt auxiliary device is safety and reliable and has perfect function, simple structure and convenient installing and removing. This provides reference for the design of the butt auxiliary device to other types steel tower of transmission line.

Numerical Analysis of a Shallow-Buried Portal in Expressway Tunnel with Weak Rockmass

2012 ◽  
Vol 256-259 ◽  
pp. 1369-1372
Author(s):  
Pan Ke Gao ◽  
Yong Li Xie ◽  
Heng Bin Wu
Keyword(s):  
Finite Element ◽  
Numerical Analysis ◽  
Finite Element Simulation ◽  
Vertical Direction ◽  
Surrounding Rock ◽  
Horizontal Direction ◽  
Element Simulation ◽  
Key Factor ◽  
Mountain Tunnels ◽  
Unsymmetrical Loading

Aiming at the problems in construction for a shallow-buried and unsymmetrical loading portal in Banzhulin Tunnel in Yu-Xiang expressway, the finite element simulation were carried on to study the behavior for bench excavation method. Main results of numerical analysis as follows:the displacement of surrounding rock of right tunnel(as AR)at the horizontal direction is large and may larger than that of the left tunnel(as AL) at the vertical direction,and the largest deformation is 22.63mm,occuring at the key point DL. Compared with the data of monitoring measurement, the correctness of this simulation was proved.The behavior for deformation and stress of mountain tunnels as Banzhulin is basically mastered,and the displacement of rockmass is the key factor in tunnelling.

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