Use of 'rapid' processing techniques by a sample of British dentists

Questionnaire surveys - sources of error and implications for design, reporting and appraisal

Questionnaire surveys of dentists are a commonly used research method which can yield important results. Nevertheless, in order to give reliable information, surveys must be carefully designed to avoid bias. The challenge of planning, designing and implementing a questionnaire study is often underestimated. While headline response rate is commonly used as an indication of survey quality, there are four potential areas of survey error. These are coverage, sampling, measurement and response. These four areas of error are discussed, with examples from the current literature, to assist readers in critically appraising questionnaire studies. We make 12 key recommendations to researchers to help avoid bias in their research; approaches to response enhancement are also considered. Reporting guidelines for questionnaire studies are suggested which improve transparency and assist in understanding of research methodologies and results. We have termed these guidelines: Reporting Items for Surveys and Questionnaires (RISQ). In conclusion, there is no single solution that can guarantee a successful study. Conversely, failure to pay careful attention to any one of many crucial aspects of survey design can be the downfall of an otherwise robust study.

An International Survey among Prosthodontists of the Use of Mandibular Implant-Supported Dental Prostheses

PURPOSE

To evaluate the use of implant-supported overdentures (IOD) and implant-supported fixed dental prostheses (IFDP) in patients with edentulous mandibles among international prosthodontists.

MATERIALS AND METHODS

A questionnaire was sent by e-mail to all clinically active prosthodontists in the International College of Prosthodontists with questions related to implant treatment of the edentulous mandible performed in 2015.

RESULTS

One hundred and sixteen prosthodontists from 33 countries responded to the questionnaire. The vast majority of the responding prosthodontists was faculty or worked in private practice, and the great majority had performed treatment with mandibular implant-supported dental prostheses; however, two thirds of the respondents reported that <20% of the implant patients in their clinic had received treatment related to edentulous mandibles. The majority reported using 2 implants (84%), while 13% used 4 for overdenture retention. There were great variations regarding retention systems used for mandibular IODs; the most common was individual Locator attachments. Cost was considered the most common reason to choose mandibular IOD, There was a wide variation of materials used for mandibular IFDPs. The most common combination included milled titanium frameworks and acrylic resin teeth.

CONCLUSIONS

This survey, completed by 116 prosthodontists from 33 countries, showed that implant treatment for edentulous mandibles is common, but there was great variation among the respondents regarding amount of treatments performed, design, and materials used for the implant prostheses.

Do Treatment Policies for Proximal Humerus Fractures Differ among Three Nordic Countries and Estonia? Results of a Survey Study

BACKGROUND AND PURPOSE

Proximal humerus fractures are common fragility injuries. The incidence of these fractures has been estimated to be 82-105 per 105 person-years. Treatment of this fracture, especially in the elderly, is controversial. Our study group published a systematic review of the available literature and concluded that non-operative methods are favored over operative methods in three- and four-part fractures. The aim of this multinational study was to compare treatment policies for proximal humerus fractures among the Nordic countries and Estonia.

MATERIALS AND METHODS

The study was conducted as a questionnaire-based survey, using the Internet-based program, Webropol(®) (webropol.com). The questionnaire link was sent to the surgeons responsible for treating proximal humerus fractures in major public hospitals in Estonia, Finland, Norway, and Sweden. Questionnaire included questions regarding the responder's hospital, patient characteristics, and examinations taken before decision making. Clinical part included eight example patient cases with treatment options.

RESULTS

Of the 77 recipients of the questionnaire, 59 responded; consequently, the response rate was 77%. Based on the eight presented displaced fracture examples, in both Estonia and Norway and in Finland, 41% and 38%, respectively, preferred surgical treatment with locking plate. In Sweden, the percentage was 28%. The pre- and post-operative protocols showed a similarity in all participant countries.

CONCLUSION

Our survey revealed a remarkable uniformity in the current practice of operative treatments and rehabilitation for proximal humerus fractures in the participant countries.

Questionnaire surveys of dentists on radiology

OBJECTIVES

Survey by questionnaire is a widely used research method in dental radiology. A major concern in reviews of questionnaires is non-response. The objectives of this study were to review questionnaire studies in dental radiology with regard to potential survey errors and to develop recommendations to assist future researchers.

METHODS

A literature search with the software search package PubMed was used to obtain internet-based access to Medline through the website www.ncbi.nlm.nih.gov/pubmed. A search of the English language peer-reviewed literature was conducted of all published studies, with no restriction on date. The search strategy found articles with dates from 1983 to 2010. The medical subject heading terms used were "questionnaire", "dental radiology" and "dental radiography". The reference sections of articles retrieved by this method were hand-searched in order to identify further relevant papers. Reviews, commentaries and relevant studies from the wider literature were also included.

RESULTS

53 questionnaire studies were identified in the dental literature that concerned dental radiography and included a report of response rate. These were all published between 1983 and 2010. In total, 87 articles are referred to in this review, including the 53 dental radiology studies. Other cited articles include reviews, commentaries and examples of studies outside dental radiology where they are germane to the arguments presented.

CONCLUSIONS

Non-response is only one of four broad areas of error to which questionnaire surveys are subject. This review considers coverage, sampling and measurement, as well as non-response. Recommendations are made to assist future research that uses questionnaire surveys.

Diagnostic Dental Radiation Risk during Pregnancy: Awareness among General Dentists in Tabriz

Background and aims

Pregnant women often do not receive proper dental care in emergency visits due to a lack of awareness of the effect of radiation doses and the involved risks for the fetus. The aim of the present study was to assess the awareness of general dentists practicing in Tabriz, Iran, of the risks involved during exposure to diagnostic dental radiation in pregnant women.

Materials and methods

In this descriptive/cross-sectional study, 250 general dentists, who had attended continuing education courses under the supervision of the Faculty of Dentistry, filled out questionnaires on their awareness of radiation risks. Data was analyzed by Spearman's correlation coefficient test.

Results

The mean of correct answers was 6.47±1.66, with the least and highest correct answers of 2 and 10, respectively. The highest and the lowest levels of awareness were related to the use of a lead apron (92%) and a long rectangular collimator (3.2%), respectively. There was a statistically significant correlation between the age of practitioners and awareness of radiation risks (P=0.02). However, no statistically significant correlation was observed between job experience (P=0.25) and the number of continuing education courses attended (P=0.16) and awareness of radiation risks.

Conclusion

The studied population of dentists does not seem to have the sufficient knowledge regarding the diagnostic dental radiation risk during pregnancy. Further educational courses and pamphlets are recommended for increasing their awareness of this subject.

Survey of dental radiological practice in Turkey

OBJECTIVES

The aim of this study was to determine the dentist's knowledge about dose reduction techniques, radiographic equipment and quality of dental radiographic service in general dental practice in Turkey.

METHODS

The survey was performed on 636 dentists who attended the 11th International Congress organized by the Turkish Dental Association. Information on the demographic characteristics of the dentists, radiographic equipment, techniques and processing they used and radiation protection was obtained with a 32 point questionnaire.

RESULTS

The respondents' knowledge concerning the technical details of their equipment was limited, with 512 (86.9%) not knowing the kilovoltage peak (kVp) of their machine. Only 34 (5.5%) respondents reported having rectangular collimators. The dentists had little knowledge about the speed of film they used. D-speed film was the most preferred one with 21.6%. Fifty-eight (10.2%) dentists used E-speed film and the F-speed film was used only by 13 (2.3%) dentists. The most preferred technique (62%) for periapical radiography was the bisecting angle technique. Four hundred and eighty five (82.5%) of the dentists reported that they took the radiographs by themselves.

CONCLUSIONS

In the present study, the results indicate that for minimizing any unnecessary radiation, attempts should be made to improve dentists' knowledge about radiation dose reduction techniques.

Fraudulent management of digital endodontic images

AIM

To present examples of radiographic image reconstructions in endodontic treatment, to discuss the potential problems arising from the use of image processing software and to mention some current methods to prevent such counterfeit utilization of digital endodontic radiographs.

SUMMARY

Conventional Ultra-Speed periapical films of root canal treatment were digitized with flatbed scanner (Umax Powerlook II, Umax Technologies, Inc., Taiwan). Digital images were altered with PHOTOSHOP 6.0 software (Adobe Corporation, San Jose, CA, USA). Carious lesions, periapical pathoses, fake root canals and artificial fillings were created, and inadequate treatment was corrected by application of various image manipulation functions of the software.

KEY LEARNING POINTS

Digital endodontic images can be altered with image processing software. The use of digital radiographic data inevitably raises concerns about security, reliability and the potential for fraud.

Radiographic equipment and techniques used in general dental practice: a survey of general dental practitioners in England and Wales

OBJECTIVES

The aims of this study were to determine the self-reported use of panoramic radiography, D- and E-speed film, rectangular collimation, film holders, equipment fitted with a long spacer cone (>200 mm) and the bisecting angle and paralleling techniques by general dental practitioners and to see if use was related to the dentists' age and postgraduate qualifications.

METHODS

Three mailings of a self-completion questionnaire were circulated to 800 general dental practitioners working in the National Health General Dental Service in England and Wales.

RESULTS

A response rate of 74% was achieved. Sixty-one percent of general dental practitioners reported use of panoramic equipment. Fifty percent of dentists always used E-speed film and 18% always used rectangular collimation. Sixty-eight percent of dentists always used bitewing film holders though fewer (37%) used periapical film holders. Sixty-three percent of dentists always used a long cone. The bisecting angle technique was used by 70% of dentists with 22% always using this technique for periapical radiographs. Thirty-one percent always used the paralleling technique. Use of panoramic equipment, periapical film holders, bisecting angle and paralleling techniques were associated with the dentists' age. Use of periapical film holders, bisecting angle and paralleling techniques and rectangular collimation were associated with dentists' postgraduate qualifications.

CONCLUSIONS

There are several features of radiographic equipment and techniques that can aid high quality imaging and reduce patient dose. Although a number of these are being used in general dental practice in England and Wales they have yet to achieve universal adoption.

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.

A laboratory evaluation of Ektaspeed Plus dental X-ray film

OBJECTIVES

The aim of this study was to make a laboratory evaluation of the image quality of a new dental X-ray film, Ektaspeed Plus, compared with Ektaspeed and Ultraspeed films.

METHODS

Films of each emulsion type underwent a range of exposures at both 50 kVp and 70 kVp, and characteristic curves were constructed to give a comparison of fog, speed and contrast. Line pair and contrast detail test objects were used to assess the resolution of radiographs and the ability of the two film types to reproduce minor differences in subject contrast. The sensitivity of the emulsions to safelighting for a range of times was also tested.

RESULTS

Ektaspeed Plus had the same speed, a slightly higher base plus fog density but a higher contrast (50 and 70 kVp) than Ektaspeed. The speed of Ektaspeed Plus was higher and the contrast similar to that of Ultraspeed film. Limiting resolutions of the three films were the same. There was a slightly better imaging of one contrast detail phantom with Ektaspeed Plus compared to Ektaspeed at 70 kVp only. All three emulsions were insensitive to recommended safelighting conditions.

CONCLUSION

The improved image contrast of Ektaspeed Plus may be more acceptable to dentists than Ektaspeed and lead to a greater acceptance of E-speed film, contributing to dose reduction.

A comparison of six intra-oral X-ray films

OBJECTIVES

To compare objectively and subjectively national-brand dental X-ray films with widely available and less costly brands.

METHODS

A range of dental films, including the recently released Kodak Ektaspeed Plus, was purchased from mail-order suppliers at the lowest published price. Objective measurements (film speed, contrast, fog levels, costs, physical characteristics) and subjective evaluations (ease of use, film graininess, overall appearance) were made.

RESULTS

Private-label films were obtained at less cost than those of major vendors. Not all film speeds, sizes and wrapping materials were available from individual manufacturers. Objective measures and subjective appraisals showed that Ektaspeed Plus was the fastest film and had good contrast with the clinically useful density ranges. Agfa Dentus was the next fastest film, but it had rather low contrast and was grainier than the other films. The non-proprietary brands were difficult to open with primary glove barriers, making effective infection control practices arduous. All films were relatively stable over a 16-week period regardless of storage location.

CONCLUSIONS

The major manufacturers offered more choices of film sizes and speeds than did private label suppliers. The films from the major manufacturers, although more expensive, were more conducive to effective infection control practices. Ektaspeed Plus had a performance comparable with or better than the other available films. Based on this preliminary study, it is recommended that this new film is considered as an alternative to D-speed films.

An in vitro comparison of 10 radiographic methods for working length estimation

The aim of this in vitro study was to assess the efficacy of 10 currently available methods of producing radiographic images, two conventional and eight rapid, in working length estimation. Thirty extracted teeth comprising 42 root canals were mounted in blocks of poly(methylmethacrylate) and access cavities prepared. A size 15 Hedstrom file was inserted into each root canal and sealed into position. Each tooth was imaged by 10 methods: combinations of conventional (D- and E- speed) film processed with conventional manual chemistry of two proprietary brands of rapid processing chemistry (Westone Rapid Dental and Kodak 'Rapid Access'), Super X30 packet processed film, Hanshin Hi-Fi and Nix NF45-100 films processed using their respective manufacturers' monobath solutions, and the Sens-A-Ray digital X-ray system. Comparisons of length of file visible were made between the D-speed films (conventionally processed using Kodak chemistry) and the nine other radiographic methods. No significant differences in percentage length of file seen were found between D-speed film processed with conventional chemistry and E-speed film processed with the same chemistry or between D-speed film processed with with conventional chemistry and six of the rapid imaging systems studied. The percentage length of the file visible was significantly less for Sens-A-Ray (P=0.02) and for Nix NF45-100 film (P<0.005) when compared with D-speed film processed with conventional chemistry. This difference in file length is probably not of clinical importance for the Sens-A-Ray images but may be so for the Nix images.

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

A new dental x-ray film, Kodak Ektaspeed Plus (Eastman Kodak Co., Rochester, N.Y.), was compared with Kodak Ektaspeed and Ultraspeed films. The comparison was based on objective measures (film contrast, speed, and fog levels) and subjective appraisals (film graininess and appearance). Ektaspeed Plus had higher contrast than Ektaspeed and in general similar contrast to Ultraspeed. Ektaspeed Plus was faster than Ektaspeed. Films were stored in various locations and base + fog determinations were made during a 16-week period. Ektaspeed Plus and Ultraspeed films were generally stable within this period. There were no meaningful differences in fog buildup based on storage location. Ektaspeed Plus had the least rate of buildup. Ektaspeed demonstrated the greatest rate of buildup and the greatest sensitivity to environmental factors. Periapical exposures were made of the molars of a manikin. These radiographs were subjectively assessed by three observers. The Ektaspeed Plus film was judged to appear less grainy than the Ektaspeed and to have a pleasing appearance. On the basis of the evaluations performed in this initial investigation, it was concluded that Ektaspeed Plus was superior to Ektaspeed film and was superior or equivalent to Ultraspeed film for dental radiography.

Review article: radiation protection in dental radiology

Dental radiology represents the most frequent diagnostic radiological investigation in the industrialized world, with over 16 million examinations performed annually in England and Wales alone. Although individual doses and risks are low in dental radiography, the collective dose is not inconsiderable and many examinations are performed in younger age groups. Radiation protection of patients in dental radiology is achieved in three ways: by appropriate selection criteria for patients and equipment, methods of dose limitation and quality assurance procedures. There is a lack of agreed radiographic selection criteria to guide British dentists and this may lead to overuse of certain techniques, principally panoramic radiography. In intraoral radiography the use of fast (E-speed) film and rectangular collimation offer dose reductions of approximately 50% and 60%, respectively. Constant potential X-ray units and rare-earth filtration permit further reductions. In panoramic and cephalometric radiography, improved collimation offers a simple means of dose limitation, while doses can be reduced by up to one-eighth by combining the use of constant potential X-ray units, rare-earth intensifying screens and rare-earth filtration. Lead protection of the abdomen has little relevance to radiation protection; however, thyroid shielding has some value. Concern has been expressed about the poor diagnostic quality of radiographs taken in the general dental services. Consequently a quality assurance programme plays an essential part in dental radiation protection by improving diagnostic yield and limiting repeat examinations.