Objective and subjective evaluations of Kodak Ektaspeed Plus dental x-ray film

Effects of developer depletion on image quality of Kodak Insight and Ektaspeed Plus films

OBJECTIVE

To evaluate the effect of processing solution depletion on the image quality of F-speed dental X-ray film (Insight), compared with Ektaspeed Plus.

METHODS

The films were exposed with a phantom and developed in manual and automatic conditions, in fresh and progressively depleted solutions. The comparison was based on densitometric analysis and subjective appraisal.

RESULTS

The processing solution depletion presented a different behaviour depending on whether manual or automatic technique was used. The films were distinctly affected by depleted processing solutions.

CONCLUSIONS

The developer depletion was faster in automatic than manual conditions. Insight film was more resistant than Ektaspeed Plus to the effects of processing solution depletion. In the present study there was agreement between the objective and subjective appraisals.

The effect of automated nonroller processing on the sensitometric characteristics of 3 intraoral film types

OBJECTIVES

We sought to compare the sensitometric characteristics of 3 intraoral film types processed in an automated roller solution with the characteristics of the films processed in 4 automated nonroller solutions.

STUDY DESIGN

Eastman Kodak Ultra-Speed, Flow X-ray EV-57, and Eastman Kodak InSight films were exposed to varying levels of radiation and processed in 1 automated roller solution and in 4 nonroller solutions. Speed and contrast were measured at various density levels and ranges.

RESULTS

With the exception of 1 nonroller solution, there was little difference in speed between roller and nonroller processing chemicals at various density levels. Some nonroller solutions were faster than the roller chemicals for all films. Nonroller processing mostly increased contrast compared with roller processing over various ranges.

CONCLUSIONS

Sensitometric properties of films processed in automatic nonroller solutions are comparable in many cases to those in roller solutions, sometimes resulting in greater speed and contrast. Different adjustments in exposure factors are required for specific film/processing combinations.

A comparison of Kodak Ultraspeed and Ektaspeed Plus dental X-ray films for use in endodontics

BACKGROUND

The advantage of using a faster film for length determination in endodontic therapy is obvious. However, for such a film to be generally accepted, it must demonstrate comparable diagnostic quality to traditionally used films.

METHODS

The comparative accuracy of canal length determination of Ultraspeed and Ektaspeed Plus dental X-ray films was assessed in maxillary first and second molars; for different canals, for different teeth, for different exposures, and for different examiners (five general dentists and three endodontic specialists).

RESULTS

In general, there were no significant differences between films, among examiners, or any interaction between films and exposures. That is, an assessor's ability to estimate lengths was not significantly influenced by the film type or by exposure used. There was a wide divergence in the individual assessor's ability to estimate lengths. Specialists estimated lengths more accurately than general practitioners and estimated lengths more accurately with Ektaspeed Plus film. Length determination in distobuccal and mesiobuccal canals was more accurate than in palatal canals. Most palatal canals were underestimated in length by more than 1mm. The use of file sizes larger in number than size 15 is recommended in these canals.

CONCLUSION

For length determination, Ektaspeed Plus dental X-ray film is as effective as Ultraspeed film. Given the acceptable quality and accuracy of Ektaspeed Plus film, there seems to be no clinical reason to subject patients to greater radiation by using a slower film during endodontic therapy.

Radiographic and digital imaging in periodontal practice

This review defines terms such as accuracy, validity, and reliability, which are used to describe the quality of methods for taking x-rays and for analyzing digital images. Values for these parameters are described for techniques of taking standardized x-rays such as ear-rod fixation and fixation by use of teeth with a dental impression. In addition, values are given for linear measurements on digitized images and for quantitative image subtraction. Differences are addressed between quantitative subtraction with a reference ramp and relative subtraction using the computer-assisted densitometric image analysis (CADIA) system. The relationship between radiographic bone height and clinical attachment level is also discussed. Finally, present and future use in the periodontal office of linear radiographic measurements on digital images and digital subtraction is discussed.

The influence of storage conditions on film characteristics of Ektaspeed plus and Ultra-speed films

BACKGROUND

Dental professionals were reluctant to accept Ektaspeed (Eastman Kodak Co.) intraoral film despite its X-radiation dose-sparing advantages for patients. One reason may have been Ektaspeed film's known sensitivity to long-term storage as compared with that of Ultra-speed film (Eastman Kodak Co.). In 1995, Kodak replaced Ektaspeed with Ektaspeed Plus, claiming it had better resolution and higher stability than Ektaspeed, as well as equal exposure radiation. The authors compared film response to storage condition and time for Ultra-speed and Ektaspeed Plus films.

METHODS

The authors stored 10 boxes of newly produced Ultra-speed and Ektaspeed Plus film in five locations. They conducted 23 image trials over a 26-month period, exposing each film with an aluminum step-wedge under controlled conditions. After processing the film, they measured density to calculate the film's base + fog and contrast index values.

RESULTS

The authors found significant differences in film type (P = .0002), processing status (P < .0001), storage location (P < .0001) and month of storage (P < .0001). They also found a film-type-by-location interaction (P < .0001) but did not find a film-type-by-processing interaction (P = .3271). Regression lines suggested that the optical density of base + fog levels rose more steeply for Ultra-speed film than they did for Ektaspeed Plus film. A significant association of decreasing contrast with increasing months of storage was seen with Ultra-speed film (P < .0001). There was a small increase in base + fog levels resulting from the use of used solutions over the course of the study.

CONCLUSIONS

Ektaspeed Plus film compared favorably with Ultra-speed film under all conditions.

CLINICAL IMPLICATIONS

The authors recommend the use of Ektaspeed Plus film for intraoral imaging, as its performance is comparable to that of Ultra-speed film while requiring half the X-radiation exposure to patients. Clinicians must ensure that the correct safelights and processing solutions are used before switching to the new film.

A perceptibility curve comparison of Ultra-speed and Ektaspeed Plus films

OBJECTIVE

The purpose of this study was to evaluate the subjectively assessed contrast difference between Kodak's Ultra-speed and Ektaspeed Plus dental radiography films (Eastman Kodak, Rochester, N.Y.) through the use of perceptibility curves.

DESIGN

Four series of 22 radiographs were exposed at 70 and 90 kVp with each film type by means of a Gendex 1000 dental radiography unit (Gendex Corp., Milwaukee, Wis.) for times ranging from 0.05 to 5 seconds at 10 ma. The test object consisted of a 7-mm-thick rectangular aluminum block with 10 circular depth cuts, each 2 mm in diameter, which created wells varying in depth from 50 to 500 microns. The corresponding films were processed concurrently (for 4.5 minutes) in total darkness with fresh Kodak Readymatic solutions (Eastman Kodak) held at a constant temperature of 28 degrees C. The resulting radiographs were viewed in a predetermined random order under ideal conditions by 10 dentists. The evaluators recorded the maximum number of perceptible images on each film. A pair of perceptibility curves were generated at 70 and 90 kVp by plotting the log relative exposure versus the mean number of perceptible images.

RESULTS

There was no statistical difference between the two film types with respect to the mean number of perceptible images, as analyzed by Wilcoxon's signed rank test (p = 0.22; p = 0.44).

CONCLUSIONS

There is no subjectively assessed contrast difference between Kodak s Ultra-speed and Ektaspeed Plus films at 70 and 90 kVp.

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.

In vivo study of approximal caries depth on storage phosphor plate images compared with dental x-ray film

The aim of this in vivo study was to compare approximal caries depth on storage phosphor plate images to conventional film. A Soredex Digora imaging plate was placed in a film bite-wing positioner behind a Kodak Ektaspeed Plus film package without lead foil. The effect of scattered radiation on film without lead foil with a storage phosphor plate at the back was studied in a separate in vitro experiment. Compared with film protected by lead foil, the film showed higher density, but comparable contrast. For the in vivo study, clinical bite-wing exposures were made with the setup described above, with exposure settings for Ektaspeed Plus film. A four-point scale was chosen for approximal caries depth: 0 = no caries; 1 = caries in enamel; 2 = caries reaching dentino-enamel junction; 3 = caries into dentin. The bite-wing film images were shown to a panel of four experts. Sixty surfaces were selected for observer performance, based on identical scorings of the experts consensus classification. Next, six dentists evaluated both film and storage phosphor plate images with the same four point scale. Analysis of variance revealed a significant observer and image modality effect without an interaction effect. In conclusion, caries depth on storage phosphor plate images was underestimated compared with film-based images.

Radiographic contrast. A comparative study of three dental X-ray films

OBJECTIVE

To investigate the radiographic contrast of three dental X-ray films (Ultra-speed, Ektaspeed and Ektaspeed Plus, Eastman-Kodak, Rochester, NY, USA).

METHODS

An aluminium stepwedge was radiographed for the objective assessment and a dried human mandibular segment including the teeth for the subjective evaluation. In the objective assessment, contrast was evaluated from the measured optic densities and the results analysed statistically by the Kruskal-Wallis one-way Anova and Mann-Whitney U test. Subjective evaluation was performed by 12 dentists with a range of clinical experience and scores were assigned to five dental and bony structures.

RESULTS

In the objective evaluation there was no significant difference in contrast obtained with the Ultra-speed and Ektaspeed Plus films: both had significantly better contrast than Ektaspeed film. The subjective assessment revealed that the majority of the dentists preferred either Ultra-speed or Ektaspeed Plus films for contrast.

CONCLUSION

Radiographic contrast of Ektaspeed Plus did not differ significantly from Ultra-speed and both were superior to Ektaspeed film.

Base and fog densities of fresh Ektaspeed Plus dental X-ray films

Previous findings with regard to base and fog density of Ektaspeed Plus dental X-ray films have shown increased values compared with Ektaspeed and Ultra-Speed films, but the results are contradictory. The purpose of the present study was to measure base density, using 10 different fixing solutions, and fog density, using 10 different developing solutions at temperatures varying from 16 to 30 degrees C. The 10 developers tested were intended for manual (three), semiautomatic (three), and automatic (four) processing. Base densities were nearly identical for all fixing products (range, 0.190-0.192). One group of six developers showed quite stable fog values for all temperatures (range, 0.190-0.259), whereas another group (four developers) showed increased values at increasing temperatures (range, 0.395-0.438 at 30 degrees C). It is concluded that base density is within the limits of ISO standards for most fixing products but that some developers result in fog densities that are above ISO standard limits at high temperatures.

Sensitometric and image quality performance of "rapid" intraoral film processing techniques

A number of products are available to dentists for the rapid production of intraoral radiographic films but there is little information on their relative merits. This study evaluated the performance of five "rapid" film processing products commonly used by British dentists in comparison with standard Kodak manual processing. Two Perspex contrast-detail test objects were made in order to investigate threshold contrast. Film speed, film gradient, limiting resolution and threshold contrast results are presented. Rapid processing systems possessed lower film speed when compared with Kodak Ektaspeed film and standard Kodak processing. The speed of E-speed film was found to be lower than that of D-speed film when used with Westone "Rapid X-ray" processing. Overall image quality was generally similar for all film/processing combinations evaluated, with the exception of Nix QP which gave markedly poorer image quality.