Detection Of Proximal Caries Research Articles

The detection accuracies for proximal caries by cone-beam computerized tomography, film, and phosphor plates

To evaluate the accuracy of cone-beam computerized tomography (CBCT) for the detection of noncavitated proximal caries and to compare the detection accuracies of 2 CBCT imaging systems with those based on plain-film radiographs and phosphor-plate images. Test radiographs of 39 noncavitated unrestored human permanent teeth were obtained with film, phosphor-plate, ProMax 3D, and Kodak 9000 3D imaging systems. Seven observers used a 5-level scale to evaluate test images for the presence of proximal caries. With histologic examination serving as the reference standard, observer performances were assessed with receiver operating characteristic (ROC) curves, and the areas under the ROC curves (A(z) values) for the observers, and modalities were analyzed with a repeated-measures analysis of variance. The mean A(z) values for film, phosphor plates, ProMax 3D, and Kodak 9000 3D imaging systems were 0.541, 0.523, 0.528, and 0.525, respectively (P = .763). For detecting subtle noncavitated proximal caries, the detection accuracy with the CBCT images was little better than chance performance and was similar to that with phosphor plate- and film-based intraoral images.

Effect of tube potential and image receptor on the detection of natural proximal caries in primary teeth

The aim of this study was to assess the detection of proximal caries in primary teeth at three different tube potentials using Ektaspeed films, storage phosphor plates (SPPs), and a charge-coupled device (CCD). Fifty-three extracted human primary molars with natural proximal caries were radiographed with three different imaging modalities--Digora Optime SPP system, RVGui CCD system, and Ektaspeed films--at 50-, 65-, and 70-kV tube potentials. Three observers scored the resultant images for the presence or absence of caries. The definitive diagnosis was determined by stereomicroscopic assessment. The diagnostic accuracy for each imaging modality was expressed as the area under the receiver operating characteristic curves (A(z)). Differences among the A(z) values were assessed using two-way ANOVA and t tests. Kappa was used to measure inter- and intra-observer agreement. Higher accuracy was found for SPPs compared to film and CCD images at all tube potentials. Accuracy was significantly different only at 50-kV tube setting in favor of SPPs (p < 0.05). Inter- and intra-observer agreement was high for all systems. A SPP system can be recommended for dental peadodontic clinics particularly with 50-kV tube potential for the diagnosis of proximal caries since further advantages include the elimination of chemical processing, image enhancement, and a better low-contrast detectability performance.

Diagnostic performance of the visual caries classification system ICDAS II versus radiography and micro-computed tomography for proximal caries detection: An in vitro study

Objectives The purpose of this study was: (a) to compare the visual caries classification system ICDAS II with conventional (CR) and digital radiography (DR) for diagnosis of non-cavitated caries on free proximal surfaces, (b) to examine the potential of micro-computed tomography (MCT) to substitute histological examination for the in vitro caries assessment. Methods Both proximal surfaces of 20 teeth received classification separately by two examiners by means of the diagnostic modalities examined. The teeth were sectioned and assessed for depth of the lesion. The modalities were compared in terms of degree of inter-examiner agreement, sensitivity, specificity, accuracy, positive and negative predictive value and validity. Two diagnostic thresholds were applied: no caries versus all caries scores (D1), and no dentin caries versus dentin caries (D3). Results The weighted kappa values for inter-examiner reproducibility for all diagnostic modalities were 0.51–0.81. Visual examination (ICDAS II) reached significant higher sensitivity (0.92–0.96) and negative predictive value (0.9–1) than radiography. Likewise, the radiographic modalities presented significantly higher specificity (0.93–1) and positive predictive values (0.92–1) than the ICDAS II criteria. The overall accuracy performance of radiographic modalities was related to the diagnostic threshold. MCT did not agree with histological validation at each disease severity scale. Conclusions The ICDAS II criteria are a promising tool for caries diagnosis on free proximal surfaces. DR and CR radiography present comparable performance. Furthermore, MCT is not capable of constituting a reliable alternative to histological examination for caries research.

Diagnostic accuracy of digitized conventional radiographs by camera and scanner in detection of proximal caries.

Background and aims Digital radiographs have some advantages over conventional ones. Application of digital recep-tors is not routine yet. Therefore, there is a need for digitizing conventional radiographs. The aim of the present study was to compare the diagnostic accuracy of digitized conventional radiographs by scanner and camera in detection of proximal car-ies. Materials and methods Three hundred and sixteen surfaces of 158 extracted posterior teeth were radiographed. The radiographs were digitized using a digital camera and a scanner. Five observers scored the images for the presence and depth of caries. Histopathologic sections were the gold standard. Kappa agreement coefficient was used for statistical analysis. Results Kappa agreement coefficients between the camera and the scanner and also between each one with the gold stan-dard in detecting the depth of caries were 0.504, 0.557 and 0.454, respectively. In detection of caries, the indexes were 0.571, 0.553 and 0.527, respectively. Conclusion Diagnostic accuracy of camera images in caries detection was more than that of scanned images, but there was also a moderate consistency between them. The consistency of detecting the presence of caries was more than that of detecting their depths. It seems that both digital cameras and scanners can be used interchangeably.

The Efficiency of Operating Microscope Compared with Unaided Visual Examination, Conventional and Digital Intraoral Radiography for Proximal Caries Detection

Objective. The purpose of this study was to evaluate the efficiency of operating microscope compared with unaided visual examination, conventional and digital intraoral radiography for proximal caries detection. Materials and Methods. The study was based on 48 extracted human posterior permanent teeth. The teeth were examined with unaided visual examination, operating microscope, conventional bitewing and digital intraoral radiographs. Then, true caries depth was determined by histological examination. The extent of the carious lesions was assessed by three examiners independently. One way variance of analysis (ANOVA) and Scheffe test were performed for comparison of observers, and the diagnostic accuracies of all systems were assessed from the area under the ROC curve (A z). Results. Statistically significant difference was found between observers (P < .01). There was a statistically significant difference between operating microscope-film radiography, operating microscope-RVG, unaided visual examination-film radiography, and unaided visual examination-RVG according to pairwise comparison (P < .05). Conclusion. The efficiency of operating microscope was found statistically equal with unaided visual examination and lower than radiographic systems for proximal caries detection.

Detection ofin vitroproximal caries in storage phosphor plate radiographs scanned with different resolutions

To investigate the effect of the scanning resolution of storage phosphor plate (SPP) radiographs on the detection of proximal caries lesions. 10 dentists evaluated 72 proximal surfaces of premolars with respect to caries from SPP radiographs scanned with theoretical spatial resolutions of: (1) the Digora FMX at 7.8 lp mm(-1); (2) the Digora Optime at both 7.8 lp mm(-1) and 12.5 lp mm(-1); and (3) the Dürr VistaScan at 10 lp mm(-1) and 20 lp mm(-1), respectively. The lesions were validated by histological examination. Receiver operating characteristic (ROC) analysis was employed. The A(z) value for the radiographs scanned with the Dürr VistaScan at 10 lp mm(-1) is significantly lower than those for the other series of radiographs (P = 0.000). For SPP radiographs, an increased theoretical spatial resolution per se is not related to an improved detection of proximal caries.

The Effect of Wavelet and Discrete Cosine Transform Compression of Digital Radiographs on the Detection of Subtle Proximal Caries

The study compared diagnostic performances of 2 different image compression methods: JPEG (discrete cosine transform; Joint Photographic Experts Group compression standard) versus JPEG2000 (discrete wavelet transform), both at a compression ratio of 12:1, from the original uncompressed TIFF radiograph with respect to the detection of non-cavitated carious lesions. Therefore, 100 approximal surfaces of 50 tooth pairs were evaluated on the radiographs by 10 experienced observers using a 5-point confidence scale. Observations were carried out on a standardized viewing monitor under subdued light conditions. The proportion of diseased surfaces was balanced to approximately 50% to avoid bias. True caries status was assessed by serial ground sectioning and microscopic evaluation. A non-parametric receiver operating characteristic analysis revealed non-significant differences between the 3 image modalities, as computed from the critical ratios z not exceeding ±2 (JPEG/JPEG2000, z = –0.0339; TIFF/JPEG2000, z = 0.251;TIFF/JPEG, z = 0.914). The mean area beneath the curve was highest for TIFF (0.604) followed by JPEG2000 (0.593) and JPEG (0.591). Both intra-rater and inter-rater agreement were significantly higher for TIFF (ĸ_intra = 0.52; ĸ_inter = 0.40) and JPEG2000 images (ĸ_intra = 0.49; ĸ_inter = 0.38) than for JPEG images (ĸ_intra = 0.33; ĸ_inter = 0.35). Our results indicate that image compression with typical compression algorithms at rates yielding storage sizes of around 50 kB is sufficient even for the challenging task of radiographic detection of non-cavitated carious approximal lesions.

Alternative erasing times of the DenOptix system plate: performance on the detection of proximal caries

Our aim was to investigate the DenOptix system for detection of proximal caries using alternative erasing times for the photostimulable phosphor plates. Human teeth were X-rayed with phosphor plates using different erasing times. Five observers evaluated the images for the presence of caries by scoring the proximal surfaces of each tooth. Mean pixel intensity analyses were also carried out. The erasing times were evaluated using receiver operating characteristic (ROC) curve analysis. Analysis of variance for differences among erasing times and pixel intensity values was performed, followed by linear regression analysis for correlation between these variables. The mean ROC curve for each erasing time varied from 0.61 to 0.66 (not significant). Analysis of variance did not show any significant effect of the erasing times on the pixel intensity values of the images (P > .05). Erasing times for DenOptix phosphor plates from 20 to 130 s were satisfactory for diagnosis of proximal caries, and their use is therefore feasible in clinical practice.

Film tomography compared with film and digital bitewing radiography for proximal caries detection

The purpose of this study was to evaluate the efficiency of conventional tomography for proximal caries detection compared with conventional bitewing and digital intraoral radiography. In this study, 48 extracted human posterior permanent teeth were used. Conventional bitewing radiographs, digital intraoral radiographs and conventional tomograms were obtained of the teeth. The presence or absence of caries was scored according to a five-point scale by two oral and maxillofacial radiologists. True caries depth was determined by histological examination. The diagnostic accuracy of each radiographic system was assessed by means of receiver operating characteristic (ROC) curve analysis. The mean of areas under the ROC curve (A(z)) was analysed by pairwise comparison of ROC curve. The interobserver agreement was evaluated using a t-test. The statistical analysis of A(z) scores has shown no significant difference for three imaging modalities (P>0.05). There was no statistically significant difference between interobserver agreement (P>0.05). This study has demonstrated that the diagnostic accuracy of conventional tomograms is comparable to that of conventional bitewing and digital intraoral radiographs for proximal caries detection.

Detection of proximal caries with high-resolution and standard resolution digital radiographic systems

Detection of proximal caries with high-resolution and standard resolution digital radiographic systems

In Vitro Comparison of Four Different Dental X-ray Films and Direct Digital Radiography for Proximal Caries Detection

This study investigated the efficiency of different speeds of conventional intraoral films and a direct digital system for proximal caries detection. In this study, 48 extracted human posterior permanent teeth were used. Conventional bitewing radiographs and direct digital radiographs were obtained from the teeth. Three observers independently assessed 96 proximal surfaces, each observer had 10 years of experience. The presence or absence of caries was scored according to a five-point scale. True caries depth was determined by histological examination. The diagnostic accuracy of each radiographic system was assessed by means of a receiver operating characteristic (ROC) curve analysis. The mean of areas under the ROC curve (Az) was analyzed by pairwise comparison of ROC curve. The interobserver agreement was evaluated by using ANOVA analysis. The statistical analysis of Az scores exhibited no significant difference for the five imaging modalities (p > 0.05). There was no statistically significant difference between interobserver agreements (p > 0.05). The results of this study showed that the diagnostic performance of E- and F-speed films and direct digital radiography are similar for proximal caries detection.

Detection of proximal caries with high-resolution and standard resolution digital radiographic systems

The aim of this study was to: (1) compare the diagnostic accuracy of the high-resolution and standard resolution settings of four digital imaging systems for caries diagnosis and (2) compare the effect on the diagnostic accuracy of reducing the high-resolution image sizes to the standard resolution dimensions, and vice versa. 90 extracted human premolars were mounted in groups of 5 in plaster blocks, containing 4 test teeth and 1 non-test tooth. Two blocks at a time were placed in a jig to simulate a bitewing radiograph. Radiographs were taken using four digital systems (Planmeca Dixi 2; Gendex Visualix HDI; Dürr Vistascan; Digora Optime), each at two resolution settings. Next, the teeth were sectioned and a total of 65 surfaces were incorporated in the study. Additionally, the bicubic interpolation method was applied to reduce the high-resolution original images and to enlarge the standard resolution images. The original, reduced and enlarged images were randomly shown to five observers in two random sessions. The observers were asked to assess caries depth on a 4-point scale. The observers' scores were compared with the results from a histological examination. Data were analysed using the statistical theory for multivariate discrete data. Cohen's kappa was used to determine the agreement with the gold standard. None of the comparisons between the spatial resolution settings, or the comparisons between increased or reduced image size and the original image sizes, showed significant differences in the probability of caries detection (chi2=26.59, df=26, P approximately 0.50). The four digital systems used in this study differ significantly in the probability of caries detection (chi2=41.55, df=24, P<0.02). Compared with the gold standard, the Gendex Visualix HDI CCD sensor has the highest measure of agreement (kappa=0.31). Caries diagnosis does not improve when using high-resolution settings compared with the standard settings. The use of bicubic convolution interpolation for zooming has no detectable effect on caries diagnosis and therefore is recommended to use when enlarging or reducing radiographs. The probability of caries detection, however, was different for the sensor systems of the different manufacturers.

Detection of Proximal Caries in vitro Using Standard and Task-Specific Enhanced Images from a Storage Phosphor Plate System

Eight dentists evaluated 72 proximal surfaces of premolars with respect to all caries lesions and to lesions into dentine in digital images from a storage phosphor plate system. The images were processed in four different ways: (1) the default algorithm of the standard imaging system (DF); (2) an algorithm correcting for attenuation and visual response (AV), and two proprietary caries-specific enhancement algorithms (3) K1, and (4) K2, respectively. The lesions were validated by histological examination. There were no significant differences in the areas under the receiver operating characteristic curves between differently processed radiographs for the categories of all caries lesions and caries into dentine.

In vitro assessment of cone beam local computed tomography for proximal caries detection

To compare the accuracy of local computed tomography (LCT) and conventional radiography for proximal caries detection and depth assessment. An in vitro model was used consisting of 20 extracted posterior teeth with 18 caries lesions. Local computed tomography slices were reconstructed in axial and parasagittal planes from 100 basis projections. Conventional radiographs were also acquired. Eight observers determined the presence and depth of caries lesions. Receiver operating characteristic analysis and weighted kappa statistics were used. Local computed tomography had a mean A(z) score of 0.82 (SD = 0.07) and conventional radiography of 0.79 (SD = 0.08; analysis of variance: P > .05). Interobserver agreement was moderate. The mean kappa for depth assessment was 0.68 (SD = 0.06) for LCT and 0.47 (SD = 0.08) for conventional radiography (analysis of variance: P < .05). Local computed tomography resulted in substantial and conventional radiography in moderate interobserver agreement. There is no difference between LCT and conventional radiography for proximal caries detection. Local computed tomography was more accurate for assessing caries lesion depth.

Digital camera resolution and proximal caries detection

To evaluate the diagnostic accuracy of proximal caries detection from digitized film images captured by a digital camera at different resolution settings. Twenty-five periapical radiographs of 50 premolar and 25 molar teeth were photographed using a digital camera, Sony Cyber-shot, DSC-S75 at three different resolution settings: 640 x 480, 1280 x 960 and 1600 x 1200. Seventy-five digital images were transferred to a computer, saved and opened using ACDSee software. In addition, a PowerPoint slide was made from each digital image. Five observers scored three groups of images (the films, the displayed 1:1 digital images on the ACDSee software, and the PowerPoint slides) for the existence of proximal caries using a 5-point confidence scale, and the depth of caries on a 4-point scale. Ground sections of the teeth were used as the gold standard. Az values under the receiver operating characteristic (ROC) curve of each group of images and at different resolutions were compared using the Friedman and Wilcoxon signed rank tests. Mean different values between the lesions' depth interpreted by the observers and that of the gold standard were analysed. Films showed the highest Az values. Only the 1280 x 960 images on the ACDSee software showed no significant difference of the Az value from the films (P=0.28). The digital images from three resolution settings on the PowerPoint slides showed no significant differences, either among each other or between them and the films. For caries depth, the 1280 x 960 images showed lower values of mean difference in enamel lesions compared with the other two resolution groups. This study showed that in order to digitize conventional films, it was not necessary to use the highest camera resolution setting to achieve high diagnostic accuracy for proximal caries detection. The 1280 x 960 resolution setting of the digital camera demonstrated comparable diagnostic accuracy with film and was adequate for digitizing radiographs for caries detection.

Accuracy of extraoral tuned aperture computed tomography (TACT) for proximal caries detection

The objectives of this study were to compare the difference in the accuracy of proximal caries detection by extraoral tuned aperture computed tomography (TACT), intraoral TACT, and film radiographs. Eighty proximal surfaces of 40 extracted human maxillary teeth were used. A digital sensor was the image receptor for TACT. Film radiographs were acquired using Insight film. Nine basis images were acquired to reconstruct TACT slices. Seven observers scored the presence or absence of proximal caries using the 3 imaging modalities. The true presence of caries and its depth were determined using the sectional images obtained by micro CT. Among the image modalities and observers, possible differences in the area under the receiver operating characteristic curve were assessed by analysis of variance (ANOVA). ANOVA indicated no statistically significant differences between observers (P = .845), modalities (P = .657), and observer-modality combinations (P = .593). Within the limited range of this study, extraoral TACT was not statistically different from intraoral TACT or film radiographs for proximal caries detection. This suggests that extraoral TACT may have some clinical utility for caries diagnosis and that further study may be warranted.

Extraoral imaging for proximal caries detection: Bitewings vs scanogram

The objective of this study was to compare the diagnostic accuracy of 3 extraoral imaging modalities with an intraoral bitewing radiograph for proximal caries detection. Three modalities of Cranex TOME scanograms, x-ray film and DenOptix photostimulable phosphor plates with and without digital enhancement, were compared with Insight intraoral radiographs for proximal caries detection. Nine observers evaluated images of the proximal surfaces of 45 extracted posterior teeth. The presence or absence of caries was scored using a 5-point confidence scale. The ground truth was determined from histological sections. Responses were evaluated by repeated measures analysis of variance (ANOVA) for areas under receiver operating characteristic (ROC) curves (A z ). Repeated measures ANOVA (at alpha = 0.05) demonstrated significant differences among modalities ( P = .041). Paired t tests with Bonferroni correction demonstrated that Insight was superior to only unenhanced digital scanograms ( P = .003). Mean A z scores (+/-SD) were 0.73 (+/-0.08) for Insight, 0.65 (+/-0.06) for screen/film scanogram, 0.64 (+/-0.04) for unenhanced digital scanogram, and 0.66 (+/-0.07) for enhanced digital scanogram. The performances of film-based and enhanced digital scanograms were not statistically different from Insight film for proximal caries detection. Unenhanced digital scanograms exhibited a statistically significant lower diagnostic accuracy than Insight film.

Minimum number of basis projections for caries detection with local CT

To investigate the relationship between the number of basis projections for local computed tomography (CT) and the detection of proximal caries and to find a minimum number of projections needed to maintain diagnostic accuracy. We presented observers (n = 12) with stacks of both axial and vertical CT slices of 23 extracted teeth placed in a dry human mandible. The slices were prepared with 14, 20, 33 and 100 basis projections. The observers scored the proximal surfaces for the presence of caries on a 1-5 confidence scale. The performance of the varying number of projections was compared with conventional digital radiographs. The performance of all four CT modalities was significantly better than conventional radiographs (P = 0.005 to P = 0.021) and showed a consistent increase with the number of projections. Diagnostic performance depended significantly on lesion depth (P = 0.00), but not on observer. We conclude that the number of CT projections used can be reduced at least to 20 with the diagnostic performance still markedly better than that of conventional film, provided that the observer can make use of both axial and vertical stacks of CT slices.

Grey-scale reversed radiographic display in the detection of approximal caries

Purpose of this study was to determine the influence of grey-scale reversal of digital radiographic images on the detection of proximal caries. Five observers assessed digital bitewing radiographs (Sidexis((R)), Sirona) of 320 unrestored surfaces of extracted posterior teeth embedded in 20 models, simulating pairing of maxillary and mandibular arches, using a six-category caries rating scale. Images were displayed in normal [N] and inverse [IN] mode at different image sizes (display ratio: 1:1, 1:2, 1:7) on a cathode-ray tube monitor (Nokia 446 XS) and a TFT display (Panasonic LC 50 S). Validation standard was defined as histological lesion depth. Validity was expressed as areas under receiver operating characteristic curves (AUC) calculated for two levels of histological caries penetration: presence of caries and presence of a dentine lesion. The factors 'inverse display', 'image size on-screen' 'display type' and 'disease cut-off' were analysed by repeated measures ANOVA. Inverse image display significantly influenced the diagnostic validity (P=0.014), but a reduced accuracy was only seen at the lowest image size (AUC (SE): [N] 0.64 (0.02); [IN] 0.62 (0.02)). At the validation threshold 'dentine caries' approximal caries detection deteriorated when using grey-scale reversal (AUC (SE): [N] 0.71 (0.02); [IN] 0.69 (0.02)). In conclusion, grey-scale reversal of digital radiographs did not optimise approximal caries detection and aggravated the detectability of dentinal lesions.

Comparison between RVG UI sensor and Kodak InSight film for detection of incipient proximal caries

The purpose of this study was to compare the efficacy of the four combination modes of Trophy RadioVisioGraphy UI sensor (Trex-Trophy Radiology Inc., Marne-la-Valee, France) and Kodak InSight film (Eastman Kodak Co., Rochester, NY) for detecting proximal dental caries. Thirty extracted human upper premolars were selected. Of 60 surfaces, 25 had carious lesions in the form of small cavities, and the rest showed no evidence of caries as verified by a micro computed tomogram (micro CT; XCT Research SA+, Stratec Medizintechnik GmbH, Pforzheim, Germany). All teeth were radiographed with the paralleling technique (60kV, 40 cm focus-to-sensor distance). Four combination modes (high-resolution caries mode—HRC; high-sensitivity caries mode—HSC; high-resolution periodontal mode—HRP; and high-resolution endo mode—HRE) were used. Exposure was set at 0.12 sec for HRC, 0.08 sec for HSC, 0.16 sec for HRP, 0.12 sec for HRE, and 0.16 sec for the Kodak InSight film. The resulting images were evaluated by three oral radiologists. The same three observers evaluated the digital images, and were allowed to use the contrast and brightness controls in doing so. Possible differences in ROC curve areas among image modalities were assessed by the Friedman test. The mean ROC curve areas were 0.66±0.11 for HRC, 0.78±0.02 for HSC, 0.76±0.04 for HRE, 0.77±0.04 for HRP, and 0.71±0.09 for the Kodak InSight film. There were no statistically significant differences between HRC, HSC, HRE, HRP and the Kodak InSight film in terms of proximal caries detection. The four modes of RVG UI system are each a viable alternative to intraoral film for the detection of incipient dental caries.