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Digital Radiographs (digital + radiograph)
Selected AbstractsCorrelation between early perforation of cover screws and marginal bone loss: a retrospective studyJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 1 2008Nele Van Assche Abstract Aim: This retrospective study aimed to determine the consequence of early cover screw exposure on peri-implant marginal bone level. Material and Methods: Sixty Astra Tech® MicroThread implants installed in partially edentulous jaws were compared: 20 implants were placed following a two-stage procedure and were unintentionally exposed to the oral cavity (two-stage exposed), 20 implants were placed following a two-stage procedure and were surgically exposed after a subgingival healing time of 3,6 months (two-stage submerged), and 20 implants were placed following a one-stage surgical protocol (one-stage). Digital radiographs were taken at implant placement for all implants, and after abutment surgery for the two-stage exposed and two-stage submerged groups or after 3 months for the one-stage group. Bone loss mesially and distally was measured with an on-screen cursor after calibration. Results: Mean bone re-modelling was 1.96 mm (range: 0.2,3.2 mm) around the two-stage exposed implants, 0.01 mm (range: 0.0,0.3 mm) around the two-stage submerged implants and 0.14 mm (range: 0.0,1.2 mm) around the one-stage implants. Conclusion: The unintentional perforation of two-stage implants resulted in significant bone destruction, probably because the biological width was not considered. [source] Ex vivo assessment of irrigant penetration and renewal during the cleaning and shaping of root canals: a digital subtraction radiographic studyINTERNATIONAL ENDODONTIC JOURNAL, Issue 4 2010F. Bronnec Bronnec F, Bouillaguet S, Machtou P.Ex vivo assessment of irrigant penetration and renewal during the cleaning and shaping of root canals: a digital subtraction radiographic study. International Endodontic Journal, 43, 275,282, 2010. Abstract Aim, To assess radiographically irrigant penetration in the root canal system of curved roots during root canal shaping procedures ex vivo. Methodology, Thirty extracted mandibular molar teeth with moderate to severe curvature were used. A special aiming device was used to guarantee that each successive radiograph was taken with the same positioning. The mesiolingual canal of each tooth was instrumented using the ProTaper system. For each step of the shaping procedure, two irrigation modalities were repeated in the same order. Active irrigation consisted of a 0.5-mL flush of sodium diatrizoate solution (Hypaque 50%) immediately followed by agitation with a size 08 K-file. Passive irrigation consisted of a 0.5-mL flush of sodium hypochlorite solution delivered with a syringe through a 27-gauge notched tip needle. A digital radiograph was taken after each modality and stored on computer for subsequent digital subtraction and measures of the depths of irrigant penetration. Comparisons were performed within an analysis-of-variance framework in a repeated-measures approach. Results, The penetration of irrigants was significantly greater for each successive step of the shaping procedure when the two modalities were analysed separately (P < 0.001). The difference between the two modalities was statistically significant for each step of the shaping procedure (P < 0.0001). Conclusions, Shaping root canals improved both penetration and exchange of irrigant inside the root canal system. Complete renewal of the solution was impossible to achieve with a conventional syringe delivery system and a limited volume of solution. Recapitulation with a K-file after flushing improved irrigant penetration. [source] Detection of marginal defects of composite restorations with conventional and digital radiographsEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 4 2002Rainer Haak The purpose of this study was to determine the validity of detecting approximal imperfections of composite fillings using three intraoral radiographic systems in vitro. Class II composite resin restorations (108) with three radiopacities (264, 306, 443% Al 99.5) of which 27 had marginal openings or overhangs, respectively, were conventionally (Ektaspeed plus) and digitally (Dexis, Digora) radiographed. Images were assessed by 10 observers for the presence of marginal gaps and overhangs, as well as for their need of restorative treatment according to a five-point confidence rating scale. The validity of the observations were expressed as areas under receiver operating characteristic (ROC) curves (Aroc). Repeated measures analysis of variance revealed significant effects of ,radiographic system' and ,diagnostic purpose'. Marginal overhangs (Aroc = 0.90) were significantly easier to diagnose than openings (Aroc = 0.63). Marginal gaps were better detected on conventional and Dexis radiographs than on Digora images. the range of sensitivities and specificities of the treatment decision was 0.53,0.56 and 0.87,0.88, respectively. It was concluded that the validity of detecting marginal defects of composite resin restorations based on radiographs was only slightly affected by the radiographic system being used. The diagnosis of marginal gaps frequently resulted in false-positive and false-negative decisions. [source] Accuracy of computer-automated caries detection in digital radiographs compared with human observersEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 3 2002Ann Wenzel The aim of this study was to compare diagnostic accuracy of a caries detection program with that of human observers. A total of 190 extracted teeth were radiographed with two Trophy RVG (RadioVisioGraphy) digital sensor systems. Four observers scored the approximal surfaces in all images on a disease severity scale. Each observer thereafter used the Logicon Caries Detector (LCD) program to analyse the surfaces in the digital images and recorded their outcome. To determine the true absence or presence of caries, histological validation was used. Sensitivities, specificities, positive and negative predictive values were calculated and differences between the diagnostic methods tested. Specificities for the outcome with the LCD were significantly lower for three observers than when they themselves assessed the RVG images and, correspondingly, the positive predictive values were lower for the LCD outcome for three of the observers. Sensitivity was also lower for two observers on the diagnostic threshold caries in dentine. It was concluded that the automated caries detection program is less accurate than human observers in detecting approximal caries lesions. [source] An audit of intra-oral digital radiographs for endodonticsINTERNATIONAL ENDODONTIC JOURNAL, Issue 4 2010R. Austin Aim, The aim of this study was to improve the quality of digital radiographs taken during endodontic treatment at King's College Hospital Dental Institute, UK. There were three phases. The first phase compared the Schick CDR system with Digora Optime. The second and third phases involved ways of improving the quality of the digital radiographs produced by the Schick CDR system. Methodology, The Faculty of General Dental Practitioners Royal College of Surgeons of England (FGDP) guidelines on Selection Criteria for Dental Radiography and Guidance Notes for Dental Practitioners on the Safe Use of X-Ray Equipment-National Radiological Protection Board enabled the use of a three point quality scale (one excellent, two diagnostically acceptable, three unacceptable), which took into consideration sensor angulation, positioning, contrast and focusing. The recommended FGDP guidelines are not less than 70% images scoring excellent. For the first phase 50 exposures recorded with the Schick CDR system were compared with 50 recorded using Digora Optime. For the second and third phases 50 radiographs for each phase were evaluated with images generated by the Schick system with training provided between the phases. Results, Images produced by the Schick system showed an inferior quality compared with the images generated by the Digora method. Both systems failed to reach the desired quality FGDP standard of 70% excellent (Schick 55% Digora 69%). Comparison of the results in the second and third phases showed that training the operator improved the quality but recommended the purchase of a size 1 or 0 Schick sensors to improve positioning errors. Conclusions, This study was carried out in order to minimise the ionising radiation dose to patients and to maximise the clinical and administrative benefits of using a digital system. It demonstrated an improvement in the quality of radiographs across all criteria measured up to and beyond the desired standard, from 55% of radiographs scoring excellent in the first phase to 80% in the third phase. As a result of the study it was decided to install the Schick CDR system because of the speed it produced images even though the first phase of this study demonstrated inferior image quality. The audit had clear, measurable standards with explicit targets. The audits have been through the entire audit cycle, data collection, change and a further data collection to provide evidence of the benefit of the change. A third data collection, demonstrated an ongoing commitment to quality. [source] Validation of a dental image analyzer tool to measure alveolar bone loss in periodontitis patientsJOURNAL OF PERIODONTAL RESEARCH, Issue 1 2009W. J. Teeuw Background and Objective:, Radiographs are an essential adjunct to the clinical examination for periodontal diagnoses. Over the past few years, digital radiographs have become available for use in clinical practice. Therefore, the present study investigated whether measuring alveolar bone loss, using digital radiographs with a newly constructed dental image analyzer tool was comparable to the conventional method, using intra-oral radiographs on film, a light box and a Schei ruler. Material and Methods:, Alveolar bone loss of the mesial and distal sites of 60 randomly selected teeth from 12 patients with periodontitis was measured using the conventional method, and then using the dental image analyzer tool, by five dentists. The conventional method scored bone loss in categories of 10% increments relative to the total root length, whereas the software dental image analyzer tool calculated bone loss in 0.1% increments relative to the total root length after crucial landmarks were identified. Results:, Both methods showed a high interobserver reliability for bone loss measurements in nonmolar and molar sites (intraclass correlation coefficient , 0.88). Also, a high reliability between both methods was demonstrated (intraclass correlation coefficient nonmolar sites, 0.98; intraclass correlation coefficient molar sites, 0.95). In addition, the new dental image analyzer tool showed a high sensitivity (1.00) and a high specificity (0.91) in selecting teeth with , 50% or < 50% alveolar bone loss in comparison with the conventional method. Conclusion:, This study provides evidence that, if digital radiographs are available, the dental image analyzer tool can reliably replace the conventional method for measuring alveolar bone loss in periodontitis patients. [source] Technical note: Standardized and semiautomated Harris lines detectionAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 3 2008S. Suter Abstract Arrest in long bone growth and the subsequent resumption of growth may be visible as radiopaque transverse lines in radiographs (Harris lines, HL; Harris, HA. 1933. Bone growth in health and disease. London: Oxford University Press). The assessment of individual age at occurrence of such lines, as part of paleopathological skeletal studies, is time-consuming and shows large intra- and interobserver variability. Thus, a standardized, automated detection algorithm would help to increase the validity of such paleopathological research. We present an image analysis application facilitating automatic detection of HL. On the basis of established age calculation methods, the individual age-at-formation can be automatically assessed with the tool presented. Additional user input to confirm the automatic result is possible via an intuitive graphical user interface. Automated detection of HL from digital radiographs of a sample of late Medieval Swiss tibiae was compared to the consensus of manual assessment by two blinded expert observers. The intra- and interobserver variability was high. The quality of the observer result improved when standardized detection criteria were defined and applied. The newly developed algorithm detected two-thirds of the HL that were identified as consensus lines between the observers. It was, however, necessary to validate the last one-third by manual editing. The lack of a large test series must be noted. The application is freely available for further testing by any interested researcher. Am J Phys Anthropol, 2008. © 2008 Wiley-Liss, Inc. [source] Marginal Bone Level around Implants Assessed in Digital and Film Radiographs: In Vivo Study in the DogCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 1 2000Eva Borg DDS ABSTRACT Background: One of the objectives of postoperative radiographic examinations of implants is to evaluate the marginal bone height and its changes over time. Purpose: The purpose of this study was to assess the influence of digital image processing on measurements of the marginal bone level around implants. Material and Methods: Implants in beagle dogs, used to study the development of peri-implantitis and subsequent healing following treatment, were monitored with conventional radiography and a digital image plate system. Five observers measured the distance between a reference point and the bone level. Measurements in conventional radiographs were made with the use of an x-ray viewer (2X) and a magnifying lens (7X). For the digital images, the system's built-in measuring function was used together with five image processing techniques: edge enhancement (matrixes set on 5 and 25), inverted grey scale, single color highlight, and color intensity mapping together with the brightness and contrast control. From the time of maximum breakdown and the end of the experiment, histologic values were available. Results: Differences between techniques and observers increased toward the end of the healing period. Measurements made at maximum breakdown did not differ significantly from the histologic value. Measurements made after healing all methods, except that using edge enhancement and a 25 × 25 kernel, differed significantly from the histologic value by underestimating the bone level. Conclusions: Measurements of bone level around implants from digital radiographs are as accurate and precise as those from film images. In particular cases, the use of specific image processing algorithms may improve both accuracy and precision. After healing, the histologic specimens showed an incomplete bone fill in the crater with a remaining thin layer of connective tissue in contact with the fixture, and in such situations, the morphology of the bone will give a more complicated diagnostic task. [source] Caries prevalence of permanent teeth: a national survey of children in Iceland using ICDASCOMMUNITY DENTISTRY AND ORAL EPIDEMIOLOGY, Issue 4 2010Helga Agustsdottir Agustsdottir H, Gudmundsdottir H, Eggertsson H, Jonsson SH, Gudlaugsson JO, Saemundsson SR, Eliasson ST, Arnadottir IB, Holbrook WP. Caries prevalence of permanent teeth: a national survey of children in Iceland using ICDAS. Community Dent Oral Epidemiol 2010; 38: 299,309. © John Wiley & Sons A/S Abstract,,, Objectives:, The Icelandic Oral Health Survey aimed to obtain new national data on the oral health of Icelandic children and teenagers. Methods:, A representative stratified random cluster sample of 2251 Icelandic children in first, seventh and 10th grade, aged approximately 6-, 12- and 15-years old was examined for caries prevalence using the ICDAS criteria. Bite-wing digital radiographs were obtained for the children in 7th and 10th grade. Results:, D3MFT scores by visual examination of 6-, 12- and 15-year olds were 0.12, 1.43 and 2.78 respectively but when including radiographs, the D3MFT rose to 2.11 at 12 years and 4.25 at 15 years. The Significant Caries Index, SiC, by visual examination for 12 and 15 y was 3.7 and 6.7 respectively but was 4.7 for 12 y and 8.9 for 15 y with radiographs. In all age groups and at most disease levels, caries was active in the majority of the lesions (58,100%). The percentage of children with no visually detectable caries at D3/D1 level was 93%/74% for 6 years, 48%/22% for 12 years and 35%/16% for 15 years. When radiographs were included the percentage reduced to 34%/15% for 12 years and 20%/6% for 15 years. Approximately 80% of 12- and 15-year-olds had at least one of their first molars sealed, with the mean number of sealed first molars being 2.2 among 12 y and 2.0 among 15 y. Conclusions:, Caries levels were higher than expected in this national survey and further away from the goals of the National Health Plan for 2010 than anticipated. Caries distribution was skewed with more than half of the children having low caries scores but a wide distribution of caries experience was seen among the remaining population. [source] | ||||||||||