The effective dose of different scanning protocols using the Sirona GALILEOS(®) comfort CBCT scanner.

OBJECTIVES: To determine the effective dose and CT dose index (CTDI) for a range of imaging protocols using the Sirona GALILEOS(®) Comfort CBCT scanner (Sirona Dental Systems GmbH, Bensheim, Germany). METHODS: Calibrated optically stimulated luminescence dosemeters were placed at 26 sites in the head and neck of a modified RANDO(®) phantom (The Phantom Laboratory, Greenwich, NY). Effective dose was calculated for 12 different scanning protocols. CTDI measurements were also performed to determine the dose-length product (DLP) and the ratio of effective dose to DLP for each scanning protocol. RESULTS: The effective dose for a full maxillomandibular scan at 42 mAs was 102 ± 1 µSv and remained unchanged with varying contrast and resolution settings. This compares with 71 µSv for a maxillary scan and 76 µSv for a mandibular scan with identical milliampere-seconds (mAs) at high contrast and resolution settings. CONCLUSIONS: Changes to mAs and beam collimation have a significant influence on effective dose. Effective dose and DLP vary linearly with mAs. A collimated maxillary or mandibular scan decreases effective dose by approximately 29% and 24%, respectively, as compared with a full maxillomandibular scan. Changes to contrast and resolution settings have little influence on effective dose. This study provides data for setting individualized patient exposure protocols to minimize patient dose from ionizing radiation used for diagnostic or treatment planning tasks in dentistry.

The sensitivity, specificity, and reliability of radiographic periapical diagnosis of posterior teeth.

PURPOSE: The purpose of this study was to define the percent accuracy, sensitivity, specificity, and reliability of periapical radiographic diagnosis of periapical inflammatory disease. METHOD: A total of 140 cases were reviewed under ideal viewing conditions by 6 observers. For each case, observers determined whether periapical disease was evident and rated the confidence of their interpretation. RESULTS: The mean percent accuracy was 70.2%. The mean sensitivity and specificity were 0.65 and 0.78, respectively. The intraclass correlation coefficients for intraobserver and interobserver reliability were 0.66 and 0.54, respectively. CONCLUSION: Specificity of periapical radiographic diagnosis is higher than sensitivity. These results support the current guideline for selective use of periapical views based on patient symptoms and clinical signs. Finally, dentists have a good degree of reliability on repeated evaluations, but only fair agreement when compared with other dentists reading the same radiograph.

A study of the impact of screening or selective radiography on the treatment and postdelivery outcome for edentulous patients.

OBJECTIVE: The purpose of this study was to assess the impact of radiographic findings on complete denture treatment and on the postdelivery course of those patients who had pretreatment radiographs (the screening group) and those who did not (the selection group). METHOD: In total, 375 cases were randomly selected by systematic sampling. Data collected included patient demographic information and denture history, predenture fabrication radiographic findings, and postdenture delivery complaints. RESULTS: Of the screening patients, 100% had pretreatment radiographs made; this compared with 13.5% of the selection patients. In the screening group, 68.3% of patients had one or more positive radiographic findings recorded. Of the screening patients, 8.3% received treatment before denture fabrication; this compared with 1.2% of the selection patients. Of the 375 cases, 2 screening patients had postdelivery complaints that required management other than denture adjustment. CONCLUSION: The results indicate that there is weak scientific support for the guideline recommending routine pretreatment radiography for new denture patients.

Lateral periodontal cyst: a case report and review of the literature.

A polycystic lateral periodontal cyst was observed over a period of 25 months. The case history, a description of the natural history of this lesion and its diagnostic characteristics, and a review of the literature are presented.

An analysis of the scientific basis for the radiographic guideline for new edentulous patients.

The FDA Radiology Guideline for the new edentulous patient recommends an initial survey of the arches. In the process of developing this recommendation, the expert panel reviewed the available literature and concluded that there was sufficient evidence to warrant screening radiography rather than selective radiography, which is the principle on which all the other recommendations are based. Our evaluation of the literature used by the panel for the edentulous recommendation identifies critical errors in the analysis of the data. Factors such as a vague definition of abnormality and a geographically diverse sample population might have led the expert panel to suggest a very conservative recommendation for this group of patients. The recommendation failed to consider the treatment impact of findings and was based simply on the large number of observations, regardless of their treatment or pathologic significance. However, in studies in which treatment is considered, it is clear that screening radiography for new edentulous patients does not yield sufficient clinically relevant information to support the guideline.

Osteopathia striata, short stature, cataracts, and microdontia: a new syndrome? A case report.

A case of osteopathia striata, childhood cataracts, short stature, elbow deformity, and microdontia with rhizomicry in a white male is reported. The report includes a detailed analysis of dental changes. The relationship of this syndrome to other similar conditions including osteopathia striata with cranial base sclerosis and Rothmund-Thomson syndrome are discussed.

Current trends in guideline development: a cause for concern.

Although the development and use of practice-related guidelines as educational aids has a long history in the health professions, scientific assessment indicates that they have had limited success in changing practice patterns. This is principally due to the exclusion of practitioners from the development process, and the lack of a credible scientific basis for many guidelines. Past failures have led to new methods of guideline development based on a critical analysis of scientific data. These methods, which involve legitimate professional organizations at all stages of the development process, are clearly a step in the right direction. Unfortunately, there are signs that current guideline developers still fail to recognize the critical nature of the new methods or the need for an open and inclusive development process. It is even more disquieting that the objective of some guideline developers, such as licensing bodies, is the formulation of standards or review criteria, particularly when there are very few therapeutic practices with a sufficient scientific basis to justify such a designation. National and provincial societies, as well as dental educators, need to assume a leadership role to ensure that if guidelines are required, they will be developed as credible aids for the improvement of patient care. In this paper, the authors recount why the "traditional process" of guideline development resulted in guidelines that were mistrusted by the profession and, as a result, ineffective. They also outline the widely-documented current methodology, which should be followed if guidelines are to be accepted by the profession. Finally, they discuss the critical issue of who should develop guidelines, and examine their role in dental practice and education.

Surface and internal absorbed doses in mandibular and maxillary occlusal radiography.

The objective of this study was to determine the absorbed radiation doses to various structures within the head and neck as a result of routine mandibular and maxillary occlusal radiography. Five projections were investigated: the anterior mandibular; true mandibular; anterior maxillary; lateral maxillary; and maxillary vertex occlusal radiographic views. Standard thermoluminescent dosimetry methodology was employed using a humanoid phantom of the skull. Multiple exposures were done for each view to ensure adequate precision. The absorbed doses to various locations following a single occlusal exposure are presented in centiGray (cGy). It was found that the absorbed dose values for occlusal radiography observed in this study were similar in magnitude to previously reported absorbed dose values for other forms of dental radiography. Values ranged from 0.0014 cGy to 1.301 cGy. The highest absorbed doses were generally the skin entrance doses. The results of this study provide an accurate, concise summary of surface and internal absorbed radiation doses for five commonly used occlusal radiographs. They can be used in the calculation of risk estimates for dental radiography, and may assist dentists in their discussions with patients concerned about radiation exposure.

The use of diagnostic tests to aid clinical diagnosis.

Clinical decision making in dentistry involves some uncertainty and error, but in the absence of good clinical research it is often more of an art than a science. This article demonstrates a way in which clinicians can consistently and effectively base the diagnostic process on scientific evidence. The authors examine the selection and utility of supplemental diagnostic tests, describe the properties of these tests, and explain how test results can be used to augment clinical opinion. To aid the dental clinician in the decision making process, a step-by-step strategy is presented for the detection of squamous cell carcinoma using toluidine blue dye.

A survey of the radiographic practices of general dentists for edentulous patients.

OBJECTIVE: The objective of the study was to evaluate the radiographic practice of general dentists for edentulous patients. STUDY DESIGN: A questionnaire was sent to a sample of graduates from the two Ontario dental schools. RESULTS: The adjusted response rate for the survey was 80%. Fifty-three percent of the respondents used screening radiography for new patients. The overwhelming choice for these dentists was the panoramic film. There was a significant positive association between ownership of a panoramic unit and use of this radiograph. Dentists who do not own a panoramic unit rarely chose to refer their patients for this radiograph either routinely or selectively. When dentists, rather than the auxiliaries, made the greater proportion of the radiographs, they tended to use selective radiography. Most dentists chose selective radiography for the recall patient. CONCLUSIONS: Almost half the dentists did not follow the Food and Drug Administration/American Dental Association guideline of screening radiography for the new edentulous patient. Of those dentists who did follow the guideline the vast majority both owned panoramic units and chose to use a panoramic survey. Most dentists followed the guideline for selective radiography for the recall patient.

Radiographic examination of children. A survey of prescribing practices of general dentists.

OBJECTIVE: The purpose of this article was to assess the radiographic prescribing practices of a sample of general practitioners for the pediatric dental patients in relation to current guidelines. STUDY DESIGN: Questionnaires were mailed to a sample of 963 dentists. The adjusted response was 80%. RESULTS: For the new patient under age 6, slightly more than two thirds of respondents reported the use of selective radiography. For ages 6 to 14 years, a slight majority chose a protocol of survey radiography. Of those who used a predetermined protocol, 69% chose "bite-wings only" for the child under 6 years, whereas for the child 6 to 14 years, the protocol of choice was a complete radiographic survey, predominantly the panoramic/bite-wing. For recall patients in both age groups, less than 1% of dentists used survey radiography. CONCLUSION: From our results, we concluded that the majority of dentists followed the guideline for children under 6 years. However, for children in the transitional dentition years, our respondents choices were divided between selective or survey radiography. The ambiguity in the wording or interpretation of the guideline for this age group may have contributed to this result.

Survey of radiographic practices of general dentists for the dentate adult patient.

OBJECTIVE: The purpose of this study was to assess the radiographic practices of general dentists with emphasis on the influence of education on these practices. METHODS: Data were obtained from a mail survey of a stratified random sample of 963 general practitioners in Ontario, Canada, who graduated from the two provincial dental schools. Descriptive statistics were used, and associations were tested by Pearson's chi 2 analysis. RESULTS: The adjusted response rate was 80%. For the new patient, 62% of respondents chose a type of predetermined protocol with the panoramic/bite-wing survey as the predominant choice. Only 37% of respondents chose to prescribe selectively according to the patient's needs. For recall patients, 55% of dentists used selective radiography, and of those who chose a protocol, the vast majority preferred bite-wing radiographs only. CONCLUSIONS: Three influences on the dentists' choice of radiographic examination as suggested by the data were dental education, ownership of a panoramic unit, and who exposed the radiographs. These associations were statistically significant.

A survey of radiographic techniques and equipment used by a sample of general dental practitioners.

A study of radiographic practices of general dentists was conducted by mail survey. Eighty percent of 963 dentists returned completed questionnaires. All participants resided in the province of Ontario, Canada, and were graduates of either of the two provincial dental schools. Fewer than one third of radiographs were taken by the dentist with only 10% of dentists taking three fourths or more of the radiographs in their practices. There was infrequent use of E speed film (11%) and rectangular collimation (8%). Automatic processing was used by 93% of dentists. Although the overwhelming majority of dentists used a film holder, 2% still have the patient hold the film. The type of film holder used was affected by dental school experience, whereas the use of E speed film was not.

A survey of magnetic fields in the dental operatory.

Recently, there has been growing concern regarding the biological effects of occupational exposure to weak time-varying magnetic fields, especially those in the extremely low-frequency range (0.1-100.0 Hz). This study examined some potential sources and intensities of 60 Hz magnetic fields produced in the dental environment. A random sample of general dental offices and selected specialty offices was visited, and the magnetic fields associated with ultrasonic scalers, amalgamators, composite light curing units, X-ray view boxes and chair lights were measured. The median 60 Hz field strengths measured at various running speeds (off, standby, low and high) and the distances from the equipment (0, 15 and 30 cm) ranged from 1.2 to 2,225 milligauss (mG). Field strengths fell off quickly with distance, but were less affected by the running speed of the equipment. They also varied among the five types of equipment tested. This was likely due to variations in the make, model and age of the equipment. The 60 Hz magnetic field strengths recorded in the dental operatory were comparable to those reported from measurements of common household appliances. However, in view of recent concerns with respect to the possible effects of magnetic fields, it is suggested that exposures be minimized and the concept of prudent avoidance be employed.

Osteosarcoma and fibrous dysplasia: radiographic features in the differential diagnosis: a case report.

A case of osteosarcoma misdiagnosed as fibrous dysplasia is presented to demonstrate the importance of an integrated diagnostic approach to oral lesions. The clinical and radiographic differences between fibrous dysplasia and osteosarcoma are reviewed.

The paradental cyst of the mandibular permanent first molar: report of a bilateral case.

A case of bilateral paradental cysts affecting the first permanent molars is described. Radiographic characteristics and differential interpretations of the lesion are discussed.