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PubMed2005

An overview of radiographic film holders.

OBJECTIVES: To provide an overview of radiographic film holders, from their inception in the early 1900s to present day. METHODS: A Medline literature search was conducted for dental studies that used keywords that pertain to radiographic film holders. Hand searches of the bibliographies were also conducted. Sixty articles (dating from 1896 to 1998) that describe new or improved film holders are reviewed here. RESULTS: From the earliest days of dental radiography, dentists attempted to standardize radiographic images and techniques. The focus of researchers in the 1950s to the 1970s was to develop a film holder that would hold the film and allow easy and predictable alignment of the X-ray tube. As research projects became more dependent on dental radiographic measurements, the focus shifted to producing reproducible radiographic images, from which highly repeatable measurements could be made. CONCLUSION: Existing devices have strengths and weaknesses. Readily available devices are adequate for routine clinical use; however, user-friendly and patient-friendly film-holding devices that result in highly reliable and accurate measurements have yet to be introduced.

Copying Processes↗
PubMed1997

The efficacy of caries detection using three intraoral films under different processing conditions.

This study compares the diagnostic accuracy of caries detection using Ultra-speed (Eastman Kodak), Ektaspeed (Eastman Kodak) and Ektaspeed Plus (Eastman Kodak) films after they were developed in both new and used processing solutions. Ektaspeed Plus film provided significantly better diagnostic accuracy for small proximal-surface caries limited to the outer third of the dentin than did Ektaspeed film. Ektaspeed Plus film did not differ significantly from Ultra-speed film in aiding in the diagnosis of small carious lesions, and it maintained diagnostic accuracy in used processing solutions. Dentists can offer the X-ray dose-reducing technology of Ektaspeed Plus film to their patients and maintain consistently high diagnostic quality.

Analysis of Variance↗
PubMed1995

Corrected sagittal tomography of the temporomandibular joint. Influence of errors in film and patient positioning on linear and angular measurements.

The aim of this study was to assess the variation in film and patient positioning in horizontally corrected sagittal tomography of the temporomandibular joint (TMJ). The influence of this variation on linear and angular measurements of some anatomic structures of the TMJ was also studied. There was no significant variation in film positioning in the tomograph, using a multi-film cassette. The variation in positioning the patient in the tomograph was significant when four dental assistants were asked to place the Frankfort plane parallel to the horizontal plane. The measurements with the film in a straight position were compared with the measurements with the film angulated, to simulate the mean variation in film and patient positioning. Linear and angular measurements of anatomic structures were performed in arthrotomograms of 58 joints, representing joints with superior disk position and joints with anterior disk position with and without reduction. There was a difference between the two measurements for four different distances and one angle independent of diagnosis. No differences could be found between patients belonging to the different diagnostic groups. The results indicate that variation in patient positioning influences linear and angular measurements of anatomic structures in TMJ arthrotomograms.

Analysis of Variance↗
PubMed1988

[Extension of measurable range of film dosimetry by a low energy X-ray absorption method].

The availability of an X-ray absorption technique employing a very low power X-ray tube was examined to extend measurable range for photographic film dosimetry. The X-ray tube having titanium target was operated at 8 kV and 0.2 microA to emit Ti KX-rays of moderate intensity. The degree of the Ti KX-ray absorption, defined as similar to photographic density, was measured for the two kinds of badge film, Fuji gamma-ray badge film and Kodak personal monitoring film, type 2 exposed for 60Co or 137Cs gamma-rays and developed by the respective standard procedures. The experimental results show that the dosimetric range of 0.01-100 R for the Fuji film and 0.03-1,000 R for the Kodak film may be easily measured by 1 minute counting with the relative statistical error (sigma) of 10%.

Cesium Radioisotopes↗
PubMedDate not supplied

A new approach to the film library: time-unit filing.

The installation of a new radiology information system (RIS) at Children's Hospital Medical Center of Akron in Akron, Ohio, took the radiology department into a new world of technology, but raised issues we never anticipated. The major problem the new RIS forced the department to overcome was how to eliminate the film file's reliance on a proprietary radiology numbering system. Previously, the department had used its own numbering system--a proprietary x-ray number--to file film jackets and had used the hospital-issued medical record number to access patient and payer information from the hospital information system. It became clear that we should use a single number--the medical record number--to access all data, but we wondered how that would affect our film file room. An RIS consultant suggested that we consider filing films by last date of service, a system called "time-unit filing." Time-unit filing means keeping the most recent two-weeks worth of films in the main file room. They are organized by gender in blue or pink jackets and marked alphabetically by the patient's last name in a way that makes mis-files easy to see. If a patient's film jacket is activated again, it is refiled in the current two-week time unit. Inactive jackets remain in their two-week time unit indefinitely. Time-unit filing has had many benefits for the radiology department at Children's Hospital Medical Center of Akron: fewer mis-files, less time needed for filing and searching, and successful implementation of the new RIS.

Evaluation Studies as Topic↗
PubMed1992

[Quality assurance from the viewpoint of the x-ray film industry].

The parameters of a film-screen-combination are listed in the directive to section 16 of the german X-ray Regulation. These parameters are determined by methods described in DIN standards and published by the manufacturer. Comparable but less precise parameters are determined in the Acceptance Test. For physical reasons it is not possible to determine the speed of an X-ray film or the intensification factor of a screen separately. The films, screens and processing chemicals delivered by the members of the manufacturer association ZVEI are kept below a deviation (expressed as relative contribution to the system speed S) of +/- 10% for the majority of products, the upper limit is +/- 15%. Poor storage and transport conditions may adversely affect the quality of X-ray films. A special labeling of the film box shall serve to guarantee safe distribution channels. The processing conditions are adjusted at the Acceptance Test according to the manufacturers recommendations. The Constancy Test of film processing serves to maintain these correct conditions. Methods deviating from the DIN-method are of limited (Bayerische method) or no value (Stuttgart method).

Commerce↗
PubMed2004

Bitewing film quality: a clinical comparison of the loop vs. holder techniques.

OBJECTIVE: To compare in vivo bitewing film quality using the holder versus the paper loop technique. METHOD AND MATERIALS: Four bitewing films were taken from the right and left premolar and molar regions of 45 dental students using both the bitewing holder and paper loop techniques. A total of 360 films were taken and assessed by an experienced practitioner not apprised of the bitewing technique used. Of interest were: (1) the number of overlaps and the percentage of teeth showing the alveolar crest; (2) proper film positioning; and (3) the percentage of cone cutting. A Poisson regression using generalized estimating equations (GEEs) was used to estimate the difference in overlap between the two techniques. For proper positioning and cone cutting, logistic regressions using GEEs were used. RESULTS: The average number of horizontal overlaps for the loop and holder techniques at the right premolar, right molar, left premolar, and left molar were 1.64, 2.11, 2.16, 2.78, and 1.64, 2.00, 2.00, 2.18, respectively. The loop technique was 1.11 times more likely to cause overlapping than the holder technique. The highest percentage of teeth showing the alveolar crest by the loop technique was 97.8% in the mandibular second premolar and first molar. With respect to film positioning, the loop technique was 1.12 times more likely to cause improper positioning than the holder technique. Both techniques demonstrated minimal cone cutting (1 in the loop versus 0 in the holder). CONCLUSION: The quality of bitewing films taken by the loop and holder techniques was not significantly different.

Alveolar Process↗
PubMed1990

Electrolytic recovery of silver from dental radiographic films.

Silver (Ag) was removed from unexposed Kodak X-OmatRP; T-MatG; X-Omat duplicating; and ultraspeed periapical dental radiographic films by immersing them into a fixer solution until the films were completely translucent. The silver was recovered from the fixer solution by the electrolytic plating technique. The number of unexposed films needed to be fixed in order to recover one troy ounce of silver by electrolysis was as follows: 250 panoramic films or 200 cephalometric films or 2,000 posterior periapical films. The silver was assayed for its purity by energy dispersive x-ray analysis, coupled to a scanning electron microscope. Depending on the sample tested, the purity of the silver recovered by electrolysis varied from 78 to 89 percent.

Electrolysis↗
PubMed1989

Densitometric evaluation of three intra-oral radiographic films.

The radiographic, or diagnostic, quality of the processed radiograph depends upon a number of factors, one of the most important being the characteristics of the film. The purpose of this study was to determine which of three intra-oral radiographic films, obtainable in this country, would give the best results in terms of density range, speed, contrast and base plus fog values. Agfa Dentus, Flow X-Ray and Kodak (all speed group D films) were exposed, using a calibrated G.E. 1000 x-ray generator at 65 kVp, 10 mA and 50 impulses (1 second) exposure time. The target-film-distance was 40 cm, the total filtration 2.0 mm Aluminium and the half-value layer 2.7 mm Aluminium equivalent. An aluminium step-wedge with 8 steps, in steps of 1.5 mm, and a natural premolar tooth, with a carious lesion, embedded in acrylic, were used as phantoms. An 8 mm-thick layer of base-plate wax and a 3 mm-thick lead plate were used to simulate tissue-scatter and prevent back-scatter, respectively. To determine the base plug fog value, an unexposed film from the same batch was processed simultaneously with each of the three films evaluated. All processing was done in a Dürr AC 245 L processor with automatic replenishment and a 6-minute cycle. The processing chemicals, viz., Kolchem High Stability X-ray developer and fixer, were mixed and used in strict accordance with the manufacturer's recommendations. The radiographic densities of each step of the step-wedge, and of carious and normal dentine of the phantom tooth, were determined by means of an RMI Digital Densitometer.(ABSTRACT TRUNCATED AT 250 WORDS)

Densitometry↗
PubMed1996

A prospective randomized clinical trial comparing two film-screen systems for chest radiography.

OBJECTIVE: To compare conventional and asymmetric film-screen chest radiography systems in a prospective, randomized trial. PATIENTS AND METHODS: Posteroanterior and lateral films were obtained with each system for one healthy volunteer and 49 consenting patients referred from pulmonary clinics and wards (for a total of 27 male and 23 female subjects ranging in age from 16 to 82 [mean 58] years). The radiographs, obtained and presented in random order, were reviewed and rated independently by two experienced radiologists and one resident in radiology; all observers were blinded to patient identification and film type. The Wilcoxon signed rank sum nonparametric test for paired samples was used to test for significant differences between the two film-screen systems. A second evaluation involving direct (blinded) comparison of the two types of films was then performed for each of the 25 patients in whom abnormality was noted during the first evaluation. RESULTS: For the posteroanterior radiographs, the asymmetric film-screen system was significantly better for assessing the trachea and mainstem bronchi, the descending thoracic-aortic edge, the left paraspinal line, the thoracic vertebral body interspace and the azygo-esophageal line (p < 0.05), whereas the conventional system had superior conspicuity in the lateral subpleural zones (p < 0.05). For the lateral radiographs, the asymmetric system was superior for assessing retrosternal lung markings (p < 0.05) but inferior for assessing fissures (p < 0.05). CONCLUSIONS: In general, the asymmetric system was superior for assessing mediastinal features and inferior for assessing the lateral subpleural zones in the posteroanterior radiographs. The asymmetric system was superior for assessing retrosternal lung markings and inferior for assessing fissures in the lateral radiographs. The results for the posteroanterior radiographs were consistent with the results of nonblinded studies reported elsewhere.

Adolescent↗
PubMed1997

Conversion of an infrared densitometer for radiochromic film analysis.

By the simple incorporation of a high intensity red LED into a typical infrared film densitometer, radiochromic film can be analysed using existing detectors and scanning software. Results show an accurate dose measurement using radiochromic film and this system compared to conventional detectors for percentage depth dose and penumbral measurements in high and low energy x-ray beams. A small circuit including a red Light Emitting Diode (LED) was positioned inside the film densitometer which does not obscure the infrared source. The red and infrared diodes work independently. For 6 MV x-rays, the 80%/20% penumbral width at 15 mm depth for a 10 x 10 cm field at 100 cm SSD was measured to be 3.5 mm with radiochromic film as compared to 3.3 with corrected diode measurements. Percentage depth doses were measured to within +/- 3% of ionisation chamber data at 6MV and within +/- 2% for 250 kVp x-ray with the film placed parallel to the beam direction in both cases.

Absorptiometry, Photon↗
PubMed2004

Detection of age-related macular degeneration using a nonmydriatic digital camera and a standard film fundus camera.

OBJECTIVE: To compare gradings of lesions associated with age-related macular degeneration (AMD) from digital and stereoscopic film images. DESIGN: Instrument validation study. PARTICIPANTS: Sixty-two subjects (124 eyes) with varying degrees of AMD, including no AMD. METHODS: Images of the optic disc and macula were taken using a 45 degrees digital camera (6.3 megapixels) through dark-adapted pupils and pharmacologically dilated pupils. In addition, 30 degrees stereoscopic retinal film images were taken through pharmacologically dilated pupils of the same eyes. All images were graded for drusen size, type, and area; pigmentary abnormalities; geographic atrophy; and neovascular lesions using the modified Wisconsin Age-Related Maculopathy Grading System. Exact agreement and unweighted kappa scores were calculated for paired gradings resulting from digital and film images. MAIN OUTCOME MEASURE: Agreement between gradings obtained from stereoscopic slide transparencies and digital nonstereoscopic images. RESULTS: Exact agreement between gradings of digital and stereoscopic film images taken through pharmacologically dilated pupils was 91% (kappa = 0.85) for the categories of none, early AMD, and late AMD. Exact agreement for gradings of digital images taken through dark-adapted pupils compared with gradings of film images was 80% (kappa = 0.69). Exact agreement for gradings of digital images captured through dark-adapted and pharmacologically dilated pupils was 86% (kappa = 0.78). In addition, kappa scores for agreement between different approaches for individual lesions were moderate to almost perfect. CONCLUSIONS: Gradings resulting from high-resolution digital images, especially when the pupil is pharmacologically dilated, are comparable with those resulting from film-based images. We conclude that digital imaging of the retina is useful for epidemiological studies of AMD.

Adult↗
PubMed2002

Commercial filming of patient care activities in hospitals.

Commercial filming of patient care activities is common in hospital settings. This article reviews common circumstances in which patients are commercially filmed, explores the potential positive and negative aspects of filming, and considers the ethical and legal issues associated with commercial filming of patients in hospital settings. We examine the competing goals of commercial filming and the duties of journalists vs the rights of patients to privacy. Current standards and recommendations for commercial filming of patient care activities are reviewed and additional recommendations are offered.

American Medical Association↗
PubMed1996

Surface microarchitectural design in biomedical applications: in vitro transmural endothelialization on microporous segmented polyurethane films fabricated using an excimer laser.

We describe the preparation of segmented polyurethane (SPU) films with round micropores and present a quantitative assay method of endothelial cell (EC) migration through micropores of and growth on microprocessed SPU films as an in vitro model of transmural endothelialization in open-cell-structured small-diameter vascular grafts. The micropored films, pores of which ranged from 9 to 100 microns in diameter, were microfabricated using an excimer laser. Time-dependent processes of EC ingrowth through micropores of SPU films with different pore sizes, which have a confluent monolayer sheet on one face and are cell free on the other, and subsequent endothelialization were quantitatively studied. The circular cellular sheet centered at the micropores expanded as incubation proceeded. Markedly retarded migration was found for the smallest pore size (9 microns in diameter). The larger the pore, the higher was the endothelialization rate. The endothelialization characteristics were studied on multiply microspored films of different pore sizes and densities, each of which was prepared so as to provide a fixed total pore area per unit area (0.01 mm2 per mm2). The highest endothelialization rates in an early incubation period were found on films with microspores between 18 and 50 microns in diameter.

Animals↗
PubMed1998

Oral mucosal adhesive film containing local anesthetics: in vitro and clinical evaluation.

In vitro and in vivo studies were conducted to gauge the effectiveness of a novel oral mucosa adhesive, moderately water-soluble, pliant polymer artificial dentifrice (AD) film containing dibucaine (DC) for relief of pain due to oral erosion. The film was prepared from a hydroxypropyl cellulose-M (HPC-M) ethanol solution containing varying amounts of DC, as well as polyethylene glycol. In the in vitro experiments, the disintegration of HPC-M showed a lag time of about 50 min, a much lower rate than that of drug release, which more or less leveled off after 50 min. Twenty-five percent of the DC was released from the film (0.113 and 0.225 mg/cm2) after the initial 5 min, which then reached about 80% after 50 min, the time at which the polymer began to break up. In the in vivo study, the local anesthetic effect of the film was evaluated in 23 patients (10 males, 13 females) suffering from the adverse effects of chemotherapy. When applied to the wet surface of the mucosa, the AD film absorbed moisture and showed excellent adhesion. Pain relief in patients lasted 2.2 +/- 0.21 and 4.3 +/- 0.25 h at DC doses of 0.113 and 0.225 mg/cm2, respectively. These results suggest that the AD film may cover mucositis sites of oral mucosa long enough to allow DC release and bring relief from pain arising from chemotherapy and/or radiotherapy.

Adhesives↗
PubMed2000

Synthetic absorbable film for prevention of air leaks after stapled pulmonary resection.

Staple-line reinforcement buttresses made of bovine pericardium (BP), expanded polytetrafluoroethylene (ePTFE), and so on have been shown to be effective in preventing air leaks after stapled lung volume reduction operations, and some of them have been clinically utilized. However, each buttress suffers at least one disadvantage such as risk of viral infection and chronic inflammation. A new buttress was made using a poly(L-lactic acid-co-epsilon-caprolactone) film (L/C film) and its effectiveness as a staple-line reinforcement was examined by performing lung volume reduction operation on a canine model. Soft tissue responses to the buttress were compared with those to the BP strip and the absorbable behavior was studied. The L/C film buttress was flexible and thin enough to easily cut. Death of dogs, infection, acute and prolonged air leaks, and any complications related to its use were not observed. The tissue responses to the film were more mild and favorable than those to BP. The L/C film was absorbed after the staple line was covered by a connective tissue. The results described above suggest that the buttress made of an L/C film is a promising staple-line reinforcement material.

Absorption↗
PubMed2001

Anteroposterior diameter of the vertebral canal in cervical region: comparison of anatomical, computed tomographic, and plain film measurements.

The purpose was to compare the computed tomographic and plain film measurements with those of anatomical specimens to determine the antero-posterior diameter of the spinal canal in cervical region. Antero-posterior diameters of 75 cervical vertebral canals (15 sets of C3-C7) were measured anatomically at two different levels. Computed tomographic and plain film measurements were also obtained at the corresponding levels. Considering anatomical measurements as the gold standard, plain film and computed tomographic measurements were statistically compared. Interobserver and intraobserver differences were also evaluated. At the uppermost pedicle levels, there was no statistically significant difference between plain films and anatomical measurements, a good correlation. However, at lowermost pedicle level there was a statistically significant difference between plain films and anatomical measurements but not between tomographic and anatomical measurements. Our results suggest that plain films can accurately estimate cervical spinal canal mid-sagittal diameter at the uppermost pedicle level and be used as a first step examination for the evaluation of cervical spinal stenoses.

Anthropometry↗
PubMed2001

Imprinting of chiral molecular recognition sites in thin TiO2 films associated with field-effect transistors: novel functionalized devices for chiroselective and chirospecific analyses.

(R)- or (S)-2-Methylferrocene carboxylic acids, (R)-1 or (S)-1, (R)- or (S)-2-phenylbutanoic acid, (R)-2 or (S)-2, and (R)- or (S)-2-propanoic acid, (R)-3 or (S)-3, can be imprinted in thin TiO2 films on the gate surface of ion-sensitive field-effect transistor (ISFET) devices. The imprinting is performed by hydrolyzing the respective carboxylate TiIV butoxide complex on the gate surface, followed by washing off the acid from the resulting TiO2 film. The imprinted sites reveal chiroselectivity only towards the sensing of the imprinted enantiomer. The chiral recognition sites reveal not only chiroselectivity but also chirospecificity and, for example, the (R)-2-imprinted film is active in the sensing of (R)-2, but insensitive towards the sensing of (R)2-phenylpropanoic acid, (R)-3, which exhibits a similar chirality. Similarly, the (R)-3-imprinted film is inactive in the analysis of (R)-2. The chiroselectivity and chirospecificity of the resulting imprinted films are attributed to the need to align and fit the respective substrates in precise molecular contours generated in the cross-linked TiO2 films upon the imprinting process.

Journal Article↗