Comparison of accuracy cone-beam computed tomography and digital bitewing radiography for detection of recurrent caries under various restorative materials: in vitro study

OBJECTIVE

The aim of this study was to compare and evaluate diagnostic accuracy of two different CBCT scan modes and digital bitewing radiography for detection of recurrent caries under five different restorative materials, and determine the relationship between the types of restorative materials.

MATERIALS AND METHODS

In this in vitro study, 200 caries-free upper and lower premolars and molars were selected. A standard deep Class II cavities was created in the middle of the mesial surface of all teeth. In 100 teeth of the experimental and control groups, secondary caries was artificially demineralized. All teeth were filled with five types of restorative material including two types of conventional composite resins, flow composite resin, glass ionomer and amalgam. The teeth were imaged with high resolution (HIRes) and standard CBCT scan modes and digital bitewing. The AUC, sensitivity, specificity and areas under the ROC curve were calculated and verified through SPSS.

RESULTS

CBCT technique was the best option in diagnosing recurrent caries. The diagnostic accuracy and specificity of HIRes CBCT scan mode was significantly higher than standard mode (P = 0.031) and bitewing (P = 0.029) for detection of recurrent caries, especially under composite group. There were no significant differences in accuracy value of bitewing and standard CBCT scan mode.

CONCLUSION

CBCT showed higher accuracy and specificity on the detection of recurrent caries which was more accurate than bitewing radiography. The HIRes CBCT scan mode achieved the highest accuracy and performed the best in recurrent caries detection.

Assessment of marginal gaps and image quality of crowns made of two different restorative materials: An in vitro study using CBCT images

Background

The present study assessed the quality of images and the presence of marginal gaps on cone-beam computed tomography (CBCT) images of teeth restored with all-ceramic and metal-ceramic crowns and compared the gap sizes observed on CBCT images with those obtained on micro-CT images.

Methods

Thirty teeth restored with metal-ceramic and all-ceramic crowns, properly adapted and with gaps of 0.30 and 0.50 mm, were submitted to micro-CT and CBCT scans. Linear measurements corresponding to the marginal gap (MG) and the absolute marginal discrepancy (AMD) were obtained. The objective assessment of the quality of CBCT images was performed using the contrast-to-noise ratio (CNR), and the subjective assessment was defined by the diagnoses made by five examiners regarding the presence or absence of gaps.

Results

The measurements were always higher for CBCT, with a significant difference regarding AMD. No significant difference in image quality was observed using CNR between the crowns tested. Low accuracy and sensitivity values could be observed for both crowns.

Conclusion

Marginal mismatch measures were overestimated in CBCT images. No difference in image quality was observed between the crowns. The correct diagnosis of gaps was considered low, irrespective of crown type and gap size.

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.

In vitro comparison of high-definition US, CBCT and periapical radiography in the diagnosis of proximal and recurrent caries

OBJECTIVE

To assess the in vitro performance of high-definition (HD) US, CBCT and periapical radiography for the visibility of proximal and recurrent caries in teeth with and without restoration.

METHODS

A total of 240 molar teeth were divided into eight groups each comprised of 30 teeth. Control groups consisted of teeth without caries (Group 1-4; N = 120), whereas diseased groups consisted of teeth with proximal caries (Group 5-8; N = 120 teeth). Finally, a total of four image sets were obtained as follows: i) PSP periapical radiography, ii) CBCT 0.075 mm voxel size, iii) CBCT 0.2 mm voxel size and iv) HD US images. The image sets were viewed separately by four observers by using a 5-point confidence scale. Intraclass correlation coefficients were calculated. The areas under the ROC curves were compared using chi-square tests. Significance level was set at α = 0.05.

RESULTS

Intraobserver agreement for both readings for the four observers ranged between 0.848 and 0.988 for CBCT (0.075 mm) images; 0.658 and 0.952 for CBCT (0.2 mm) images; 0.555 and 0.810 for periapical images; 0.427 and 0.676 for US images. Highest AUC values were found for CBCT (0.075 mm) images and lowest for US images. Statistically significant differences were found among CBCT (0.075 mm) images and US images (p < 0.001), CBCT (0.2 mm) images and US images (p < 0.001) and periapical images and US images (p < 0.001) for the detection of proximal caries.

CONCLUSION

Periapical and CBCT images outperformed HD US imaging in the detection of proximal dental caries.

Quantitative assessment of artefacts and identification of gaps in prosthetic crowns: a comparative in vitro study between periapical radiography and CBCT images

OBJECTIVES

To evaluate, in an in vitro study, the quantity of artefacts generated by two different restorative materials, and to determine the diagnostic accuracy of cone beam CT (CBCT) scans and periapical radiographs in identifying gaps in prosthetic crowns.

METHODS

A total of 30 teeth restored with metal-ceramic (n = 15) and all-ceramic (n = 15) crowns, properly adapted and with 0.30- and 0.50 mm gaps, underwent CBCT exams (with voxel sizes of 0.25 and 0.30 mm) and periapical radiographs. The artefacts generated by two different crowns were quantified and compared by the Mann-Whitney test. In addition, five examiners evaluated the presence or absence of gaps in periapical radiographs and CBCT images. The accuracy of tests was determined by the area under the receiver operatring characteristic curve and these values were compared by using the Kruskal-Wallis test.

RESULTS

There was no significant difference in artefact values between the different restorative materials and the different resolutions of CBCT images. Regarding the accuracy of the tests evaluated, periapical radiography and CBCT with voxel size 0.25 mm showed the best performance for smaller gaps (0.30 mm). For larger gaps (0.50 mm), all exams tested showed the same performance.

CONCLUSIONS

Periapical radiography was still the most cost-beneficial method for the diagnosis of maladaptation in dental restorations. CBCT exams did not improve accuracy in detecting gaps in prosthetic crowns.

Accuracy of various imaging methods for detecting misfit at the tooth-restoration interface in posterior teeth

Purpose

The present study aimed to evaluate which of the following imaging methods best assessed misfit at the tooth-restoration interface: (1) bitewing radiographs, both conventional and digital, performed using a photostimulable phosphor plate (PSP) and a charge-coupled device (CCD) system; (2) panoramic radiographs, both conventional and digital; and (3) cone-beam computed tomography (CBCT).

Materials and Methods

Forty healthy human molars with class I cavities were selected and divided into 4 groups according to the restoration that was applied: composite resin, composite resin with liner material to simulate misfit, dental amalgam, and dental amalgam with liner material to simulate misfit. Radiography and tomography were performed using the various imaging methods, and the resulting images were analyzed by 2 calibrated radiologists. The true presence or absence of misfit corresponding to an area of radiolucency in regions subjacent to the esthetic and metal restorations was validated with microscopy. The data were analyzed using a receiver operating characteristic (ROC) curve, and the scores were compared using the Cohen kappa coefficient.

Results

For bitewing images, the digital systems (CCD and PSP) showed a higher area under the ROC curve (AUROC) for the evaluation of resin restorations, while the conventional images exhibited a larger AUROC for the evaluation of amalgam restorations. Conventional and digital panoramic radiographs did not yield good results for the evaluation of resin and amalgam restorations (P<.05). CBCT images exhibited good results for resin restorations (P>.05), but showed no discriminatory ability for amalgam restorations (P<.05).

Conclusion

Bitewing radiographs (conventional or digital) should be the method of choice when assessing dental restoration misfit.

Comparison of cone beam computed tomography and digital intraoral radiography performance in the detection of artificially induced recurrent caries-like lesions

OBJECTIVES

The aim of this study was to compare the performance of cone beam computed tomography (CBCT) and digital radiography in the detection of artificial recurrent caries-like lesions under amalgam and composite fillings.

STUDY DESIGN

The study included class II cavities in 30 molars that had been filled with amalgam. Fifteen of those molars had the restoration-enamel interface artificially demineralized. Phantoms were prepared, and CBCT images were acquired with 2 units in 3 voxel sizes (K9000, 0.076 mm; i-CAT, 0.2 mm and 0.4 mm). Intraoral radiographs were obtained with 3 systems (Digora, VistaScan, and RVG-6100). Amalgam fillings were then replaced by composite, and new images were obtained. Three examiners assessed all of the images. Sensitivity, specificity, accuracy, and receiver operating characteristic curve were calculated and verified through analysis of variance and the Tukey test.

RESULTS

There were no significant differences in sensitivity and specificity when the same restorative material was present or when the restorative materials were compared with the imaging technique as a constant. As for accuracy and receiver operating characteristic curve, there were statistically significant differences when the 2 materials were compared, and there were differences in the amalgam group when the imaging modalities were compared.

CONCLUSIONS

CBCT performed similarly to intraoral radiography in detecting demineralization under restorations. However, the voxel size and the type of restorative material influenced its performance.

Effects of various cone-beam computed tomography settings on the detection of recurrent caries under restorations in extracted primary teeth

Purpose

The aim of this study was to assess the ex vivo diagnostic ability of 9 different cone-beam computed tomography (CBCT) settings in the detection of recurrent caries under amalgam restorations in primary teeth.

Materials and Methods

Fifty-two primary teeth were used. Twenty-six teeth had dentine caries and 26 teeth did not have dentine caries. Black class II cavities were prepared and restored with amalgam. In the 26 carious teeth, recurrent caries were left under restorations. The other 26 intact teeth that did not have caries served as controls. Teeth were imaged using a 100×90-mm field of view and a 0.2-mm voxel size with 9 different CBCT settings. Four observers assessed the images using a 5-point scale. Kappa values were calculated to assess observer agreement. CBCT settings were compared with the gold standard using a receiver operating characteristic analysis. The area under the curve (AUC) values for each setting were compared using the chi-square test, with a significance level of α=.05.

Results

Intraobserver kappa values ranged from 0.366 to 0.664 for observer 1, from 0.311 to 0.447 for observer 2, from 0.597 to 1.000 for observer 3, and from 0.869 to 1 for observer 4. Furthermore, interobserver kappa values among the observers ranged from 0.133 to 0.814 for the first reading and from 0.197 to 0.805 for the second reading. The highest AUC values were found for setting 5 (0.5916) and setting 3 (0.5886), and were not found to be statistically significant (P>.05).

Conclusion

Variations in tube voltage and tube current did not affect the detection of recurrent caries under amalgam restorations in primary teeth.

Comparison of Cone-Beam Computed Tomography and Intraoral Radiography in Detection of Recurrent Caries under Composite Restorations

Abstract Secondary caries is the most common cause of dental restoration failures. This study aimed to compare the diagnostic accuracy of conventional and digital intraoral radiography and cone beam computed tomography (CBCT) for detection of recurrent caries around composite restorations. mesio-occluso-distal (MOD) cavities were prepared using bur on 45 extracted sound human molar teeth. The teeth were divided into 3 groups. In the control group, cavities were restored with composite resin after etching and bonding (n=15). In Group 2, 500-μm thick wax was placed over the buccal, lingual and gingival walls and the cavities were restored with composite resin. Group 3 specimens were subjected to pH cycling and artificial caries were created on the buccal, lingual and gingival walls. The cavities were restored with composite. Conventional and digital photo-stimulable phosphor (PSP; Optime) radiographs and two CBCTs images (NewTom 3G and Cranex 3D) were obtained from them. Presence or absence of caries in the cavity walls was assessed on these images. Data were analyzed using Kappa statistic. The diagnostic accuracy of CBCT was significantly higher than that of digital and conventional intraoral radiography (p<0.05). The accuracy was 0.83, 0.78, 0.55 and 0.49 for CBCT Cranex 3D, CBCT NewTom 3G, conventional and digital intraoral radiography, respectively. CBCT has a higher diagnostic accuracy than digital and conventional intraoral radiography for detection of secondary caries around composite restorations.

Cone Beam Computed Tomography- An Effective Tool in Detecting Caries Under Fixed Dental Prostheses

INTRODUCTION

Caries under restorations is the most common reason for re-treatment and replacement in restorative failures. To avoid failures of fixed dental prostheses, it is important to diagnose caries under it earlier. Without image degradation and metal artifacts, Cone Beam Computed Tomography (CBCT) can be the solution to detect caries without removing fixed dental prostheses.

AIM

The aim of this study was to determine the efficacy of CBCT in detecting caries under fixed dental prostheses.

MATERIALS AND METHODS

Each specimen was scanned with CBCT for evaluation of secondary caries under fixed prostheses. Exposure parameters were 60 kVp and 3mA. Field of View (FOV) used was 8cm X 8cm. According to International Caries Detection and Assessment System (ICDAS) criteria, six Grade 6 carious extracted teeth were selected. All teeth were prepared with four different specimens - full metal, metal-ceramic, full ceramic and metal-acrylic crowns for each tooth. Each specimen was scanned by CBCT. T-test was performed for mean gray value differences between caries and noncaries regions of each material. Gray values were recorded and evaluated for different parameters using two-way analysis of variance.

RESULTS

Significant differences were found with respect to material (full metal, metal-ceramic, full ceramic and metal-acrylic) and situation (caries/noncaries) (p<0.001). There were no significant differences with respect to location (anterior or posterior). Mean gray values of caries and noncaries regions were found to be different for each material.

CONCLUSION

CBCT can be used as a post-treatment diagnostic technique for detecting caries under fixed prostheses without removing it.

Diagnostic accuracy of different display types in detection of recurrent caries under restorations by using CBCT

OBJECTIVES

To assess the in vitro diagnostic ability of CBCT images using seven different display types in the detection of recurrent caries.

METHODS

Our study comprised 128 extracted human premolar and molar teeth. 8 groups each containing 16 teeth were obtained as follows: (1) Black Class I (Occlusal) amalgam filling without caries; (2) Black Class I (Occlusal) composite filling without caries; (3) Black Class II (Proximal) amalgam filling without caries; (4) Black Class II (Proximal) composite filling without caries; (5) Black Class I (Occlusal) amalgam filling with caries; (6) Black Class I (Occlusal) composite filling with caries; (7) Black Class II (Proximal) amalgam filling with caries; and (8) Black Class II (Proximal) composite filling with caries. Teeth were imaged using 100 × 90 mm field of view at three different voxel sizes of a CBCT unit (Planmeca ProMax(®) 3D ProFace™; Planmeca, Helsinki, Finland). CBCT TIFF images were opened and viewed using custom-designed software for computers on different display types. Intra- and interobserver agreements were calculated. The highest area under the receiver operating characteristic curve (Az) values for each image type, observer, reading and restoration were compared using z-tests against Az = 0.5. The significance level was set at p = 0.05.

RESULTS

We found poor and moderate agreements. In general, Az values were found when software and medical diagnostic monitor were utilized. For Observer 2, Az values were statistically significantly higher when software was used on medical monitor [p = 0.036, p = 0.015 and p = 0.002, for normal-resolution mode (0.200 mm(3) voxel size), high-resolution mode (0.150 mm(3) voxel size) and low-resolution mode (0.400 mm(3) voxel size), respectively]. No statistically significant differences were found among other display types for all modes (p > 0.05). In general, no difference was found among 3 different voxel sizes (p > 0.05). In general, higher Az values were obtained for composite restorations than for amalgam restorations for all observers. For Observer 1, Az values for composite restorations were statistically significantly higher than those of amalgam restorations for MacBook and iPhone (Apple Inc., Cupertino, CA) assessments (p = 0.002 and p = 0.048, respectively).

CONCLUSIONS

Higher Az values were observed with medical monitors when used with dedicated software compared to other display types which performed similarly in the diagnosis of recurrent caries under restorations. In addition, observers performed better in detection of recurrent caries when assessing composite restorations than amalgams.

Detecting Secondary Caries Lesions

Secondary caries lesions are the main late complication of dental restorations, limiting their life span and generating costs by repeated reinterventions. Accurate detection of secondary lesions is crucial for estimating the true burden of the disease and allocating appropriate treatments. We aimed to assess the accuracy of detection methods for secondary caries lesions. Clinical or in vitro studies were included that investigated the accuracy of 5 detection methods—visual, tactile, radiography, laser fluorescence, quantitative light-induced fluorescence—of natural or artificially induced secondary lesions, as verified against an established reference test. Sensitivity, specificity, positive and negative likelihood ratios, as well as diagnostic odds ratios were calculated and publication bias assessed. From 1,179 screened studies, 23 were included. Most studies were performed in vitro, on permanent posterior teeth, and had high risk of bias or applicability concerns. Lesions were on proximal (14 studies) or other surfaces and adjacent to amalgam (16 studies) or tooth-colored materials. Visual ( n = 11), radiographic ( n = 13), and laser fluorescence detection ( n = 8) had similar sensitivities (0.50 to 0.59) and specificities (0.78 to 0.83), with visual and laser fluorescence assessment being more accurate on nonproximal surfaces and adjacent to composites, respectively. Tactile assessment ( n = 7) had low accuracy. Light-induced fluorescence ( n = 3) was sensitive on nonproximal surfaces but had low specificities. Most analyses seemed to suffer from publication bias. Despite being a significant clinical and dental public health problem, detection of secondary caries lesions has been assessed by only a few studies with limited validity and applicability. Visual, radiographic and laser-fluorescence detection might be useful to detect secondary lesions. The validity of tactile assessment and quantitative light-induced fluorescence remains unclear at present.

Association and comparison between visual inspection and bitewing radiography for the detection of recurrent dental caries under restorations

PURPOSE

The aim of the present study was to investigate, in posterior teeth, the association between the characteristics of the margins of a restoration visually inspected and the presence, under restorations, of recurrent or residual dental caries detected by radiographic examination. Furthermore, the agreement between visual inspection and radiographs to detect dental caries was assessed.

METHODS

Eighty-five permanent molars and premolars with resin restorations on the interproximal and/or occlusal faces, from 18 patients, were submitted for visual inspection and radiographic examination. The visual inspection involved the criteria of the International Caries Detection and Assessment System (ICDAS). Bitewing radiographs were used for the radiographic examination. Logistic regression was used to analyse the association between the characteristics of the margins of a restoration assessed by visual inspection (absence of dental caries, or early, established, inactive and active lesions) and the presence of recurrent caries detected by radiographs. Kappa coefficients were calculated for determining agreement between the two methods.

RESULTS

The Kappa coefficient for agreement between visual inspection and radiographic examination was 0.19. Established lesions [odds ratio (OR) = 9.89; 95% confidence interval (95% CI): 2.94-33.25; P < 0.05] and lesion activity (OR = 2.57; 95% CI: 0.91-7.27; P < 0.05) detected by visual inspection, were associated with recurrent or residual dental caries detected by radiographs. Restorations with established and active lesions at the margins had a greater chance of exhibiting recurrent or residual lesions in the radiographic examination.

CLINICAL SIGNIFICANCE

The present findings demonstrate that restorations with established and active lesions at the margins when visually inspected often require removal and retreatment.

Is it possible to diagnose caries under fixed partial dentures with cone beam computed tomography?

OBJECTIVE

The goal of this study was to determine the possibility of detecting/diagnosing caries under fixed partial dentures using cone beam computed tomography.

STUDY DESIGN

A range of teeth with grade 3 to 6 caries, according to International Caries Detection and Assessment System criteria, were selected. All teeth were prepared, and three different specimens- zirconia full-ceramic, lithium disilicate full-ceramic, and metal-supported ceramic crowns-were built for each tooth. Each specimen underwent scanning by cone beam computed tomography. Opacity values were recorded and evaluated using two-way analysis of variance. The Tukey test was performed for material and slice differences, and the t test for mean gray value differences, between caries and noncaries regions of each material.

RESULTS

Significant differences were detected with respect to horizontal location (anterior/posterior), restoration type (crown/bridge), material (zirconia/lithium disilicate/metal), and situation (caries/noncaries) (P < .001). Mean gray values of caries and noncaries regions were found to differ for each material. There were no significant differences with respect to vertical position.

CONCLUSIONS

Cone beam computed tomography can be used as a posttreatment diagnostic technique for detecting caries under high-atomic-number fixed plate dentures. By combining high resolution and accuracy, cone beam computed tomography could provide the means for diagnosing caries without removing fixed plate dentures.

Posttreatment diagnosis of caries under fixed restorations: a pilot study

STATEMENT OF PROBLEM

Conventional radiographic techniques are insufficient for detecting caries under fixed restorations or for acquiring clear images of the disease. Advanced radiographic techniques such as cone beam computerized tomography may be a solution.

PURPOSE

The purpose of this study was to assess the viability of detecting and characterizing caries under complete-ceramic and metal-supported crowns by using cone beam computerized tomography.

MATERIAL AND METHODS

A grade 6 carious molar tooth according to the International Caries Detection and Assessment System criteria was selected. The tooth was prepared, and 3 different crowns were fabricated in a dental laboratory: yttria tetragonal zirconia polycrystal (Y-TZP) ceramic, lithium disilicate ceramic, and metal ceramic. The crowns were placed on the prepared tooth, and each specimen was subjected to cone beam computerized tomography. Opacity values were recorded and evaluated with 2-way ANOVA. Multivariate comparisons (Tukey was performed to assess the mean gray value differences of the materials between caries and dentin, and the Mann-Whitney U test was performed to assess the mean gray value differences between caries and dentin for each material (α=.05).

RESULTS

Carious borders and cavities were detected under the 3 ceramic crown specimens with a cone beam computerized tomography radiographic technique. The statistical analysis of the radiopacity mean gray value was at the borderline of significance for the specimen radiographies. Significant differences were found with respect to materials, location, and the interaction between these 2 factors (P<.001).

CONCLUSIONS

Cone beam computerized tomography can be used as a posttreatment diagnostic technique for detecting caries under high atomic numbered crowns and partial fixed dental prostheses.