Intraoral versus extraoral bitewing radiography in detection of enamel proximal caries: an ex vivo study

Management of a clinical case of caries lesions by undergraduate dentistry students

Background

Dental caries remains the most prevalent chronic disease worldwide. Hence the importance of detecting and evaluating caries and combining this with additional diagnostic methods to ensure the best treatment. The main objective was to study what is the sensitivity and specificity for detecting initial and cavitated caries lesions by students in third, fourth and fifth year of the Degree in Dentistry at the University of Barcelona, analysing if there is any difference between the diagnoses and treatments among the different years and each student's clinical experience. It was also determined if they apply the techniques based on the concepts of minimal intervention.

Material and Methods

An observational cross-sectional study using an online survey was performed, based on a real clinical case, aimed at the students in third, fourth and fifth year of the Degree in Dentistry at the University of Barcelona.

Results

Most of the respondents (72.13%) observed demineralization or cavities caused by caries in the clinical image and all in the radiographic image (100%). Meanwhile, they showed a more conservative attitude in the treatment of occlusal face, where 23.08% in 4.6 and 46.25% in 4.7 indicate filling of pits and fissures. On the other hand, on the proximal faces, they directly opted for a class II filling (95% in 4.5 distal, 94% in 4.6 mesial and 84% in 4.6 distal). Eighty-five percent of the students considered applying techniques based on the concepts of minimal intervention.

Conclusions

The students use similar criteria when diagnosing and treating possible caries lesions regardless of academic year or clinical experience. The personal evaluation of the application of the concepts of minimal intervention does not correlate with the clinical attitude to those cases. Key words:Dental caries, caries diagnosis, caries management, questionnaire.

Eligibility of a novel BW + technology and comparison of sensitivity and specificity of different imaging methods for radiological caries detection

OBJECTIVES

Bitewing radiography is considered to be of high diagnostic value in caries detection, but owing to projections, lesions may remain undetected. The novel bitewing plus (BW +) technology enables scrolling through radiographs in different directions and angles. The present study aimed at comparing BW + with other 2D and 3D imaging methods in terms of sensitivity, specificity, and user reliability.

MATERIALS AND METHODS

Five human cadavers were used in this study. In three cadavers, natural teeth were transplanted post-mortem. BW + , two-dimensional (digital sensors, imaging plates, 2D and 3D bitewing radiographs) and 3D methods (high and low dose CBCT) were taken. Carious lesions were evaluated on 96 teeth at three positions (mesial, distal, and occlusal) and scored according to their level of demineralization by ten observers, resulting in 35,799 possible lesions across all observers and settings. For reference, µCT scans of all teeth were performed.

RESULTS

Overall, radiographic evaluations showed a high rate of false-negative diagnoses, with around 70% of lesions remaining undetected, especially enamel lesions. BW + showed the highest sensitivity for dentinal caries and had comparatively high specificity overall.

CONCLUSIONS

Within the limits of the study, BW + showed great potential for added diagnostic value, especially for dentinal caries. However, the tradeoff of diagnostic benefit and radiation exposure must be considered according to each patient's age and risk.

Does enhancement filter application increase the diagnostic accuracy of misfit detection at the implant-prosthesis interface?

STATEMENT OF PROBLEM

Misfits at the implant-prosthesis interface may increase complications in dental implants and affect peri-implant tissue health. Periapical radiographs are the most used imaging examinations for detecting misfits at the implant-prosthesis interface, although digital systems have largely replaced film-based radiographs. Whether postprocessing tools such as enhancement filters assist diagnosis by highlighting misfits is unclear.

PURPOSE

The purpose of this in vitro study was to assess the influence of enhancement filter application in the diagnostic accuracy of misfit detection at the implant-prosthesis interface.

MATERIAL AND METHODS

A total of 32 dental implants were placed in dry human mandibles. A polyester strip was inserted at the implant-prosthesis interface to simulate a 50-μm misfit; prosthetic crowns installed directly on the implant platforms were used as controls. Standard paralleling periapical images were acquired by using a semidirect system (photostimulable phosphor plate) with the application of Highlight, Invert, and Colorization filters, as well as a direct system (metal oxide complementary semiconductor sensor) with filters Sharpness 3, Invert, and Pseudocolorization. Oral radiologists evaluated the images with and without the application of filters. The areas under the receiver operating characteristics curves (Az values), sensitivity, specificity, accuracy, positive predictive value, and negative predictive values were calculated. The Az values were compared with the receiver operating characteristic (ROC) curves comparison test of the Epidat 3.1 software (α=.05).

RESULTS

Although images without filter application presented descriptively higher diagnostic values than those with filter application, the Az values for images with and without filter application in both semidirect and direct systems showed no significant differences (P>.05).

CONCLUSIONS

Enhancement filter application did not significantly influence the diagnostic accuracy of misfit detection at the implant-prosthesis interface.

ORCA-EFCD consensus report on clinical recommendation for caries diagnosis. Paper I: caries lesion detection and depth assessment

OBJECTIVES

The aim of the present consensus paper was to provide recommendations for clinical practice considering the use of visual examination, dental radiography and adjunct methods for primary caries detection.

MATERIALS AND METHODS

The executive councils of the European Organisation for Caries Research (ORCA) and the European Federation of Conservative Dentistry (EFCD) nominated ten experts each to join the expert panel. The steering committee formed three work groups that were asked to provide recommendations on (1) caries detection and diagnostic methods, (2) caries activity assessment and (3) forming individualised caries diagnoses. The experts responsible for "caries detection and diagnostic methods" searched and evaluated the relevant literature, drafted this manuscript and made provisional consensus recommendations. These recommendations were discussed and refined during the structured process in the whole work group. Finally, the agreement for each recommendation was determined using an anonymous Delphi survey.

RESULTS

Recommendations (N = 8) were approved and agreed upon by the whole expert panel: visual examination (N = 3), dental radiography (N = 3) and additional diagnostic methods (N = 2). While the quality of evidence was found to be heterogeneous, all recommendations were agreed upon by the expert panel.

CONCLUSION

Visual examination is recommended as the first-choice method for the detection and assessment of caries lesions on accessible surfaces. Intraoral radiography, preferably bitewing, is recommended as an additional method. Adjunct, non-ionising radiation methods might also be useful in certain clinical situations.

CLINICAL RELEVANCE

The expert panel merged evidence from the scientific literature with practical considerations and provided recommendations for their use in daily dental practice.

Radiation doses in extraoral bitewing radiography compared with intraoral bitewing and panoramic radiography

OBJECTIVES

We compared the effective dose (E) and thyroid equivalent dose of 2 extraoral bitewing (EOBW) units and compared E with their respective panoramic (PAN) modes and with intraoral bitewing radiography (IOBW).

STUDY DESIGN

Child and adult anthropomorphic phantoms with dosimeters were used to evaluate Orthophos SL, Rayscan α+, and 1 intraoral unit using rectangular and circular collimation. Extraoral bitewing thyroid equivalent dose was assessed without and with thyroid shielding.

RESULTS

Child and adult E values of EOBW were lower with Orthophos (3.6 and 8.6 μSv) than with Rayscan (28.1 and 30.2 μSv). For IOBW, E was lower with rectangular vs circular collimation for child (7.0 vs 11.8 μSv) and adult (4.6 vs 14.2 μSv). E values of EOBW were lower than PAN for Orthophos. The IOBW E was lower than Rayscan EOBW for child (≤11.8 vs 28.1 μSv) and adult (≤14.2 vs 30.2 μSv). Adult E for rectangular IOBW (4.6 μSv) was lower than EOBW with Orthophos (8.6 μSv) and Rayscan (30.2 μSv). Thyroid shielding reduced EOBW thyroid equivalent dose with Rayscan in the adult from 190.7 to 89.0 μSv.

CONCLUSION

Orthophos provides significantly lower EOBW E than Rayscan, thus EOBW recommendations must be unit specific. For children, Orthophos EOBW could be an alternative to IOBW, for which rectangular collimation is recommended. Thyroid shielding reduced adult Rayscan equivalent dose but added imaging artifacts.

Development and validation of a clinical phantom reproducing various lesions for oral and maxillofacial radiology research

Purpose

The objective of this study was to propose a method for developing a clinical phantom to reproduce various diseases that are clinically prevalent in the field of dentistry. This could facilitate diverse clinical research without unnecessarily exposing patients to radiation.

Material and Methods

This study utilized a single dry skull, which was visually and radiographically examined to evaluate its condition. Existing lesions on the dry skull were preserved, and other relevant lesions were artificially created as necessary. These lesions were then documented using intraoral radiography and cone-beam computed tomography. Once all pre-existing and reproduced lesions were confirmed by the consensus of 2 oral and maxillofacial radiologists, the skull was embedded in a soft tissue substitute. To validate the process, cone-beam computed tomography scans and panoramic radiographs were obtained of the fabricated phantom. All acquired images were subsequently evaluated.

Results

Most lesions could be identified on panoramic radiographs, although some sialoliths and cracked teeth were confirmed only through cone-beam computed tomographic images. A small gap was observed between the epoxy resin and the bone structures. However, 2 oral and maxillofacial radiologists agreed that this space did not meaningfully impact the interpretation process.

Conclusion

The newly developed phantom has potential for use as a standardized phantom within the dental field. It may be utilized for a variety of imaging studies, not only for optimization purposes, but also for addressing other experimental issues related to both 2- and 3-dimensional diagnostic radiography.

Automatic exposure compensation of digital radiographic technologies does not affect alveolar bone-level measurement

OBJECTIVE

To evaluate whether the automatic exposure compensation in the presence of high-density materials can affect the measurement of alveolar bone level.

METHODS

Thirty regions of seven dry skulls and six mandibles were radiographed with and without a high-density material, using two digital radiographic technologies: photostimulable phosphor plate (PSP, Digora Optime) and sensor (CMOS, Digora Toto), totaling 120 images. The distances from the cement-enamel junction to the alveolar bone crest were measured using cone-beam computed tomography (CBCT) images to represent the reference standard. The same measurements of alveolar bone level and the average of the pixel values of the image were evaluated on the radiographs. Paired t test compared the average pixel values and alveolar bone-level measurements between images with and without high-density material. One-way analysis of variance compared the difference between radiographic and CBCT measurements (α = 0.05).

RESULTS

The high-density material reduced the pixel values in PSP (p = 0.002) and CMOS (p < 0.001) technologies, demonstrating the AEC functioning in both technologies. There was no difference in bone-level measurements between the images without and with the high-density material for both technologies (p ≥ 0.091), or between the tomographic and radiographic measurements (p ≥ 0.319).

CONCLUSION

In the presence of high-density material, the automatic exposure compensation reduces the average pixel values of the images (i.e., images get darker), but does not influence the radiographic measurements of alveolar bone level.

Influence of radiographic acquisition methods and visualization software programs on the detection of misfits at the implant-abutment interface: An ex vivo study

STATEMENT OF PROBLEM

Misfits at the implant-prosthesis interface may compromise implant-supported prostheses. Periapical radiographs are frequently used to detect misfit and can be obtained by using digital or film-based systems; however, which radiographic acquisition method and visualization software program provides the greatest accuracy is unclear.

PURPOSE

The purpose of this ex vivo study was to evaluate the influence of 3 radiographic acquisition methods (complementary metal oxide semiconductor [CMOS] sensor, phosphor plates, and radiographic films) and 2 visualization software programs (proprietary and third-party) on the detection of misfits at the implant-prosthesis interface.

MATERIAL AND METHODS

Thirty-two dental implants were placed in dry human mandibles. Misfits were simulated by inserting a 50-μm polyester strip at the implant-prosthesis interface; prosthetic crowns installed directly over the implant platforms were considered as controls. Standard parallel periapical radiographs were obtained by using a CMOS sensor, a phosphor plate, and radiographic films. Five dentists assessed the digital radiographs for the presence or absence of misfits at the implant-prosthesis interface by using the proprietary software program and a third-party software program; film-based radiographs were evaluated on a light box. The area under the receiver operating characteristic curves (Az values) were compared (α=.05); sensitivity, specificity, accuracy, positive predictive value, and negative predictive values were also estimated.

RESULTS

All diagnostic and Az values were higher for the phosphor plate than for the CMOS sensor and the film-based methods (P<.05), regardless of the viewing software program used (proprietary or third-party) (P>.05).

CONCLUSIONS

The use of phosphor plates positively influenced the diagnostic accuracy for the detection of misfits at the implant-prosthesis interface, irrespective of the viewing software program used.

The impact of different dental restorations on detection of proximal caries by cone beam computed tomography

OBJECTIVES

To evaluate the effects of different types of restorations on observer ability to detect proximal caries in CBCT images.

MATERIALS AND METHODS

Forty human premolars and molars with artificial proximal caries were placed proximal and distal to 5 molars having different restorations (amalgam, composite, resin-modified glass ionomer cement (RMGIC) fillings, zirconia, and lithium disilicate crowns) and a non-restored molar. CBCT scans were obtained using i-CAT^® Next Generation. Images were rated twice by 2 observers. The exact depth of artificial caries was histologically established. Sensitivity, specificity, and area under the receiver operating characteristic curve (Az) values were calculated.

RESULTS

Caries detection in teeth surfaces mesial and distal to amalgam showed compromised specificity and accuracy. Moreover, caries detection in teeth surfaces mesial to zirconia crown showed low sensitivity, specificity, and accuracy. Capability of CBCT in detection of proximal caries in teeth adjacent to composite, RMGIC, and lithium disilicate was comparable to those adjacent to non-restored molar.

CONCLUSIONS

CBCT scans performed for tasks other than caries detection should be assessed for proximal caries in absence of any restorations as well as in presence of composite, RMGIC fillings, and lithium disilicate crowns. However, CBCT should not be used for proximal caries detection in teeth adjacent to amalgam and teeth surfaces mesial to zirconia crowns.

CLINICAL SIGNIFICANCE

It is important to investigate the influence of artifacts produced by various restorations on CBCT-based caries detection to optimize CBCT benefits, caries diagnosis and avoid unnecessary treatment of sound surfaces.

Extraoral bite-wing radiographs: A universally accepted paradox

BACKGROUND

The development of specialized panoramic radiograph machine software has spawned the introduction of an innovative and promising dental radiographic examination type: extraoral bite-wings. But does this unconventional type of imaging belong in the bite-wing family? Is there any relationship at all to the conventional bite-wing radiograph?

OBJECTIVES

The purpose of this article is not to make a case for the diagnostic effectiveness of one system over the other; this is best left to further clinical evaluation. Instead, the authors intend to provide an outline of a few key and distinguishing elements of the intraoral bite-wing radiographic examination followed by those of the extraoral panoramic substitute and draw attention to the importance of reimagining the increasingly universal naming convention of this novel radiographic examination, the paradoxical "extraoral bite-wing radiograph", based on the fundamental principles of each of these imaging systems.

PRACTICAL IMPLICATIONS

The accuracy of clinical and technical terminology in oral radiography is of paramount importance to both the profession and patients, especially when considering emerging technologies.

Radiographic Interpretation in Oral Medicine and Hospital Dental Practice

Oral medicine practice includes the diagnosis and nonsurgical treatment of oral and orofacial diseases and oral manifestations of systemic conditions. Oral medicine specialists in medical and dental settings often require imaging in assessment and treatment of these conditions. This article reviews imaging that may be used in practice, particularly as relevant for facial pain, bone conditions, and salivary gland disease. It reviews imaging that may be considered in a hospital setting for assessment of admitted patients, patient evaluation before surgical procedures, and provision of dentistry in a hospital setting for patients who cannot submit to treatment in an outpatient setting.

Guidelines for oral and maxillofacial imaging: COVID-19 considerations

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus causing the current coronavirus disease 2019 (COVID-19) pandemic, is not only highly infectious but can induce serious outcomes in vulnerable individuals including dental patients and dental health care personnel (DHCPs). Responses to COVID-19 have been published by the Centers for Disease Control and Prevention and the American Dental Association, but a more specific response is required for the safe practice of oral and maxillofacial radiology. We aim to review the current knowledge of how the disease threatens patients and DHCPs and how to determine which patients are likely to be SARS-CoV-2 infected; consider how the use of personal protective equipment and infection control measures based on current best practices and science can reduce the risk of disease transmission during radiologic procedures; and examine how intraoral radiography, with its potentially greater risk of spreading the disease, might be replaced by extraoral radiographic techniques for certain diagnostic tasks. This is complemented by a flowchart that can be displayed in all dental offices.

COVID-19 and beyond: implications for dental radiography

Due to the coronavirus pandemic, all routine dental care in the UK ceased on 25 March 2020. Liverpool University Dental Hospital (LUDH) responded by commencing an emergency dental service on the same date. Clinicians were redeployed within the Hospital to meet the needs of the service, including staffing of the radiology department. LUDH followed Royal College recommendations by taking extraoral radiographs in preference to intraoral radiographs due to the risk of inducing an aerosol. Issues were identified with clinical diagnosis from sectional panoramic radiographs, which led to the introduction of extraoral bitewings being taken as an alternative. A quality assurance audit found that these images provided a substantially lower radiation dose and produced excellent quality images with improved diagnostic accuracy. This article aims to summarise how our radiography practices changed in response to the coronavirus and how the lessons that we have learnt provide an opportunity to modify and improve future practice, beyond the pandemic.

Application of panoramic radiography with a multilayer imaging program for detecting proximal caries: a preliminary clinical study

OBJECTIVE

The aim of this study is to introduce a novel program of panoramic radiography that shows 41 multilayer images from the buccal to lingual aspects in a region of interest, and to evaluate the effectiveness of this program for detecting proximal caries.

METHODS

In total, 480 premolars and molars on 30 panoramic radiographs taken with the multilayer imaging program were included in this study. The presence or absence of caries in 960 proximal surfaces was assessed by three experienced oral and maxillofacial radiologists as a consensus-based gold-standard. Two general dentists evaluated and scored proximal caries on 980 surfaces on panoramic radiographs with and without the multilayer imaging program. The two general dentists' scores were compared with the gold-standard, and were analyzed for sensitivity, specificity, positive predictive value, negative predictive value, and area under the receiver operating characteristic (ROC) curve with and without using the program. The area under the ROC curve was analyzed using STATA/SE 13.1.

RESULTS

When the multilayer imaging program was used for panoramic radiography, the inter- and intraobserver agreement of the two general dentists improved. All values, including the area under the ROC curve, were higher when the multilayer imaging program was used than when it was not used. The area under the ROC curve showed a statistically significant improvement only in Observer 1, whose diagnostic ability was poorer than that of Observer 2.

CONCLUSIONS:O

This multilayer imaging program might help the inexperienced dentist to improve the diagnostic accuracy of proximal caries. If further studies would be performed in various clinical application, it could be useful when intraoral radiography taking is difficult for reasons such as mouth-opening limitations and the gag reflex of the patients.

Clustering effects of oral conditions based on clinical and radiographic examinations

OBJECTIVES

The intra-class correlation coefficient (ICC) is a measure of intra-subject clustering effects. A priori estimates of the ICC and the associated design effect (DE) are required for sample size estimation in clustered studies, and should be considered during their analysis, too. We aimed to determine the clustering effects of carious lesions, apical lesions, periodontal bone loss, and periodontal pocketing, assessed in clinical or radiographic examinations.

METHODS

A subsample of patients (n = 175) enrolled in the fifth German Oral Health Study provided data on clinically determined carious teeth (i.e., with untreated carious lesions, WHO method) as well as teeth with periodontal pocketing (i.e., with maximum probing-pocket-depths ≥ 4 mm). A sample of panoramic radiographs (n = 85) from randomly chosen patients, examined from 2010 to 2017 at the Charité dental hospital, provided data on radiographically determined carious teeth (i.e., with lesions extending into dentine or enamel), teeth with apical lesions (determined by dentists via majority vote), and teeth with periodontal bone loss (≥ 20% of root-length). The ICC and its 95% confidence interval (95% CI) were determined.

RESULTS

There were 3839 and 1961 teeth assessed in clinical and radiographic evaluations, respectively. For clinically or radiographically determined carious lesions, the ICC (95% CI) was 0.20 (0.16-0.24) or 0.19 (0.14-0.25), respectively. For clinical pocketing or radiographic bone loss, the ICC was 0.40 (0.35-0.46) or 0.30 (0.24-0.38), respectively. The lowest ICC was found for apical lesions at 0.08 (0.06-0.13).

CONCLUSIONS

The ICC varied between assessment methods and conditions. Clustered trials should account for this during study planning and data analysis.

CLINICAL RELEVANCE

Within the limitations of this study, and considering the risk of selection bias and the limited sample sizes of both datasets, clustering effects were substantial but varied between dental conditions. Studies not accounting for this during planning and analysis may yield misleading estimates if clustering is present.

Perioperative dental screening and treatment in patients undergoing cardiothoracic surgery and interventional cardiovascular procedures. A consensus report based on RAND/UCLA methodology

AIM

To reach a consensus on a consistent strategy to adopt when screening patients for dental/periodontal infections and on the feasibility of providing dental treatment before cardiothoracic surgery, cardiovascular surgery or other cardiovascular invasive procedures.

METHODOLOGY

A panel of experts from six Italian scientific societies was created. The deliberations of the panel were based on the RAND method. From an initial systematic literature review, it became clear that a consensually validated protocol for the reproducible dental screening of patients awaiting cardiac interventions was considered mandatory by professionals with expertise in the dental, cardiologic and cardiac surgery areas. However, a systematic review also concluded that the treatment options to be provided, their prognosis and timing in relation to the physical condition of patients, had never been defined. Following the systematic review, several fundamental questions were generated. The panel was divided into two working groups each of which produced documents that addressed the topic and which were subsequently used to generate a questionnaire. Each member of the panel completed the questionnaire independently, and then, a panel discussion was held to reach a consensus on how best to manage patients with dental/periodontal infections who were awaiting invasive cardiac procedures.

RESULTS

A high level of agreement was reached regarding all the items on the questionnaire, and each of the clinical questions formulated were answered. Three tables were created which can be used to generate a useful tool to provide standardized dental/periodontal screening of patients undergoing elective cardiovascular interventions and to summarize both the possible oral and cardiovascular conditions of the patient and the timing available for the procedures considered.

CONCLUSIONS

Upon publication of this consensus document, the dissemination of the information to a wide dental and cardiac audience should commence. The authors hope that this consensus will become a model for the development of a dedicated protocol, ideally usable by heart and dental teams in the pre-interventional preparation phase.

A comparison of diagnosis of early stage interproximal caries with bitewing radiographs and periapical images using consensus reference

OBJECTIVES:

The purpose of this study was to assess the diagnostic property of intraoral bitewing radiographs (BTW) for early stage interproximal caries, and to compare them with periapical radiographs (PA) at different levels of caries progression.

METHODS:

A total of 241 interproximal surfaces of BTW and corresponding PAs were used. Seven teaching faculty consisting of three oral and maxillofacial radiologists, two operative faculty, and two prosthodontists evaluated the images. The observers graded images as either "intact", "enamel caries <1/2 width", "enamel caries >1/2 width", or "caries into dentin". The gold-standard was established by consensus of two experienced faculty with 35 years and 27 years of experience. Specificity, sensitivity, positive-predictive value, and negative-predictive value were calculated for the different level of caries progression. Furthermore, receiver operating curves) of BTW and PAs of each evaluator were made and the area under the curve of BTW and PAs were compared.

RESULTS:

There was no significant difference in the specificity of BTW and PAs. BTW showed significantly higher sensitivity than PAs in all levels of caries progression (p<0.01). Positive-predictive value and negative-predictive value of BTWs were also significantly higher than PAs. One-way ANOVA and Tukey HSD test showed a significant difference in sensitivity with different levels of caries progression. The average area under the curve was significantly higher for BTWs than PAs (p<0.01).

CONCLUSIONS:

BTWs offer a significant advantage over PAs in the diagnoses of early stages of interproximal carious lesions.

Accuracy of extraoral bite-wing radiography in detecting proximal caries and crestal bone loss

BACKGROUND

Extraoral bite-wing (EB) radiography is an imaging technology used in dentistry. The authors conducted an in vivo study comparing the accuracy of intraoral bitewing (IB) radiographs and EB radiographs for proximal caries and bone loss diagnosis.

METHODS

The authors recruited 116 patients who received IB radiographs to receive EB radiographs. The 5 calibrated authors made a consensus radiographic diagnosis of proximal caries and crestal bone loss. For this study, they assumed IB radiographs as the criterion standard. Next, they obtained EB radiographs for the 116 patients and calculated sensitivity, specificity, and false-positive rates against each patient's IB radiograph.

RESULTS

The patients' EB radiographs revealed a significantly greater number of caries and crestal bone loss findings compared with their IB radiographs. The EB radiographs had a high to excellent sensitivity and moderate to low specificity of caries and crestal bone loss findings, respectively. Considering IB radiographs to be the criterion standard, the false-positive rate for EB radiographs was moderate for caries and high for bone loss diagnosis.

CONCLUSIONS

The EB radiographs, which generate fewer images of overlapping proximal surfaces, have the advantage of detecting more carious lesions and bone loss findings than the IB radiographs do, but with the disadvantage of more false-positive diagnoses. Further research is needed to evaluate if the false-positive findings represent true carious lesions and bone loss.

PRACTICAL IMPLICATIONS

EB radiography is a promising technology, which has several advantages over traditional IB radiography. Clinicians should be aware of false-positive diagnosis of caries and bone loss with EB radiography.

Numerical Evaluation of Image Contrast for Thicker and Thinner Objects among Current Intraoral Digital Imaging Systems

The purpose is to evaluate the performance of current intraoral digital detectors in detail using a precise phantom and new method. Two aluminum step wedges in 0.5 mm steps were exposed by two photostimulable phosphor plate (PSP) systems—one with automatic exposure compensation (AEC) and the other without AEC—and a CCD sensor. Images were obtained with 3 doses at 60 kV. The effect of metallic material also was evaluated. The contrast-to-noise ratio (CNR) for thinner steps and the low contrast value (LCV) for thicker steps were obtained. The CCD system was the best under all conditions (P < 0.001), although the Gray value was sensitive to the dose, and the Gray value-dose relation varied greatly. The PSP system with AEC was superior to that without AEC for the LCV (P < 0.001) but was inferior to it regarding the CNR (P < 0.001). CNR and LCV in the PSP system without AEC were not affected by the metallic plate. Intraoral digital imaging systems should be chosen according to their diagnostic purpose. PSP system with AEC may be the best for detecting molar proximal caries, whereas the PSP system without AEC may be better for evaluating small bone regeneration in periodontal disease. The CCD system provided the best performance.