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1.
Xeroradiographs and conventional film radiographs (D- and E-speed) were compared in a clinical study with the use of one-half complete-mouth radiographs for the detection of recurrent dental caries in 200 teeth. The results indicated that film was the most useful in identification of noncarious restored teeth (91% correct versus 79% correct for xeroradiography); however, xeroradiography was better than film for detection of recurrent caries (67% versus 53%). With ROC analysis, both film and xeroradiography were equally useful, having the same ROC value of 0.78. At rates of 67% and 53% for detection of the presence of recurrent caries, neither imaging system can overcome basic geometric limitations of superimposition of metallic restorations. Thus, there is the continued need for careful clinical assessesment of existing restorations for the presence of recurrent caries.  相似文献   

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Xeroradiographs and conventional film radiographs (D- and E-speed) were compared in a clinical study with the use of 1 complete-mouth radiographs for (1) the presence of interproximal caries and (2) the determination of the depth of interproximal caries with the use of 200 tooth surfaces. In addition, an analysis of correct classification rates making a comparison of the same techniques was conducted. The results with the use of ROC analysis indicated that when a comparison was made of xeroradiography and D- and E-speed film, all techniques were equally useful. A broad range of observer ROC area values was found, indicating that diagnostic performance varies greatly with observer. The results of the diagnostic decisions made on carious surfaces versus noncarious surfaces indicated that all techniques tested were similar: 90% correct for noncarious surfaces and 77% correct for carious surfaces.  相似文献   

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This study determined the perceived strengths and weaknesses of xeroradiography, D-speed film, and E-speed film for intraoral radiography. Results indicated that xeroradiography was preferred for the imaging of structures useful in periodontics and endodontics whereas film demonstrated a low level of image artifacts and was judged to be better for the imaging requirements of routine restorative dentistry. D-speed film was rated higher than E-speed film. These subjective assessments are similar to previously reported pilot studies but differ from previously published objective studies, which showed no significant difference between the three imaging techniques. Although there are substantial subjective differences between xeroradiography, D-speed film radiography, and E-speed film radiography, all the techniques provide more than the threshold level of necessary diagnostic information and all techniques portray adequate information for evaluation of common abnormalities encountered in the oral cavity.  相似文献   

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This article assesses the diagnostic utility, radiation dose, equipment reliability, patient acceptance, and costs associated with D-speed film, E-speed film, and dental xeroradiographs for intraoral imaging. From the analysis and review of laboratory studies and clinical trials, conclusions and recommendations are offered.  相似文献   

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目的:介绍自行设计标准牙片持片器的设计、工作原理,并评价用该持片器拍摄牙片的可重复性。方法:选择具有健康、完整牙列志愿者20例。同一牙位拍摄2组牙片,一组为咬翼片,另一组为标准牙片投照装置拍摄的定位牙片,拍摄间隔为1h,获得2组20对牙片。测量釉牙骨质界-牙槽嵴顶距离(CEJ-AC)及邻牙釉牙骨质界点间距离(CEJ-CEJ)。结果:主观评价显示该投照装置的可重复性好,传统咬翼片可重复性较差,前后2次投照咬翼片CEJ-AC及CEJ-CEJ差值比标准牙片大,差异有显著性(P<0.05)。结论:使用标准牙片持片器拍摄的牙片可重复性好于咬翼片,可明显提高牙片图像的可重复性。  相似文献   

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The purpose of this study was to compare reproducibility in the assessment of caries lesion behaviour in digital subtraction images and conventional radiographs. Ninety-seven pairs of conventional film bite-wings were included. The radiographs had been taken with a Kwik-Bite filmholder without further standardisation. The selection criterion was that at least one surface imaged in a bite-wing pair should show progresssion of a caries lesion from the first exposure to the second. The time interval between the bite-wings was 1-2 years. The radiographs were scanned into a personal computer and the two images from the same patient subtracted. Seven observers scored the subtraction images and the conventional films. The scale was based on no change/ change in surface appearance scored in the following categories: 0 = no change; 1 = development of a new caries lesion in enamel; 2 = development of caries lesion in enamel and dentine/progression of an existing enamel lesion into dentine/progression of a dentinal lesion further into dentine; 3 = development of secondary caries; 4 = new filling/change of filling/extension of filling. Cohen's kappa coefficients were calculated for intra- and inter-observer agreement for the two radiographic methods separately. The kappa value served as the statistical sampling unit for testing differences between the two methods (Wilcoxon's test for ranked pairs). The average intra-observer kappa value was 0.875 (range 0.775-0.958) for the subtraction images and 0.758 (range 0.560-0.890) for the conventional radiographs. The difference was statistically significant (p<0.05). For inter-observer agreement, the kappa values were lower than for intra-observer agreement. The average value was 0.678 (range 0.485-0.754) for the subtraction images and 0.701 (range 0.497-0.817) for the conventional radiographs (p>0.1). This study suggests a new way of comparing reproducibility in terms of kappa values between diagnostic methods in clinical studies where accuracy cannot be evaluated. The subtraction method may be useful in the assessment of caries lesion behaviour in the clinic.  相似文献   

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Detection of periapical bone pathosis is an important part of the diagnostic process in dentistry. Xeroradiographs and E-speed films were taken to evaluate and to compare the diagnostic value for the radiographic interpretation of periapical lesions. Thirty-four patients undergoing endodontic treatment were chosen. Simultaneous exposures of the radiographic film and the xeroradiographic plates were made. The samples were viewed and categorized by the examiners using the following scores: 0 = unacceptably poor, 1 = poor but diagnostic, 2 = adequate for diagnostic information, and 3 = optimal for diagnostic information. A paired sample t test was performed on the result of the evaluation by the two examiners, and both showed that there were no significant difference at p less than 0.05 between xeroradiography and conventional radiography. A two-sample t test was performed on the means of the two examiner's evaluation, and there was no significant difference at p less than 0.05 between the means.  相似文献   

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Eagle first described vague orofacial pain associated with styloid elongation in 1937. Since that time, many authors have described the various clinical symptoms, radiographic features, and treatment regiments seen with Eagle's syndrome. Two cases of Eagle's syndrome treated surgically are presented in this article. Both extraoral and intraoral approaches were separately used. These two surgical approaches are critically discussed in depth. The extraoral approach is advocated. In addition, diagnostic procedures and nonsurgical treatment alternatives are discussed.  相似文献   

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In Japan, some dentists use indirect-exposure (screen) films for intraoral radiography, without the use of intensifying screens. The purpose of the present investigation was to determine whether film speed, inherent contrast, and latitude of Japanese indirect-exposure films used without intensifying screens were comparable to those of direct-exposure (non-screen) films used for intraoral radiography. The characteristic curves of Kodak Ektaspeed ("E" speed) and Ultra-speed ("D" speed) films were used as standards for comparison. Indirect-exposure films without intensifying screens were extremely slow compared with direct-exposure "E" and "D" speed films. Therefore, they should not be used for intraoral radiography because they needlessly expose the patient to excessive X-ray radiation. The direct-exposure films Hanshin Hi-Fi and Hanshin New Silver were equivalent in speed, higher in contrast, and narrower in latitude than Kodak Ektaspeed film. In general, the indirect-exposure films had lower speed, lower contrast and wider latitude than the direct-exposure films. Their speed and contrast would have been increased if intensifying screens had been used. Therefore, indirect-exposure films without intensifying screens should not be used for intraoral radiography.  相似文献   

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OBJECTIVE: Automatic exposure control has been used successfully in medicine to improve image quality and reduce the number of retakes necessitated by inadequate operator selection of exposure factors. The purpose of this study was to assess the influence of automatic exposure control on panoramic image quality. STUDY DESIGN: A total of 352 patients were imaged with either the OP 100 or the Orthophos Plus panoramic machine. An expert consensus panel judged film quality using a 5-point scale. Differences in quality that would have resulted from the use of operator-determined exposures were calculated through use of an algorithm validated with test images of a human phantom. RESULTS: McNemar's test demonstrated significant improvements in quality with automatic exposure control (P = .001) in comparison with manual exposure control. No quality difference was found between the 2 machines (P = .9661). Manual exposure selection by oral and maxillofacial radiology residents was better than selection by technologists and assistants (P = .006). CONCLUSIONS: This study confirms the utility of automatic exposure control for panoramic radiography.  相似文献   

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Abstract –  Aim : To compare intraoral occlusal (OC) and periapical (PA) radiographs vs. limited cone beam computed tomography (CBCT) in diagnosing root-fractured permanent teeth. Material and methods :  In 38 patients (mean age 24 years, range 8–52 years) with 44 permanent teeth with horizontal root fractures, intraoral radiographs (PA and OC) and limited CBCT were used to evaluate the location (apical, middle, cervical third of the root) and angulation of the fracture line. Furthermore, the conventional radiographs and CBCT images were compared for concordance of fracture location. Results :  In the PA and OC radiographs, 28 fractures (63.6%) were located in the middle third of the root, 11 (25.0%) in the apical third and 5 (11.4%) in the cervical third. The PA/OC radiographs and the sagittal CBCT images (facial aspect) yielded the same level of root fracture in 70.5% of cases (31 teeth; 95% CI: 54.1–82.7%). The PA/OC radiographs and sagittal CBCT images (palatal aspect) showed the same level of root fracture in 31.8% of cases. There was a statistically significant association between the angle at which the root fracture line intersected the axis of the tooth and the level of root fracture in the facial aspect of the sagittal CBCT images. Conclusions :  The diagnosis of the location and angulation of root fractures based on limited CBCT imaging differs significantly from diagnostic procedures based on intraoral radiographs (PA/OC) alone. The clinical significance for treatment strategies and for the prognosis of root-fractured teeth has to be addressed in future studies.  相似文献   

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