Introducing an Innovative Approach for Managing Proximal Non-Cavitated Carious Lesions in Juvenile Permanent Dentition: Combining Orthodontic Separators and Silver Fluoride Application

BACKGROUND AND OBJECTIVES

The aim was to introduce an innovative, easy and cheap clinical approach for the control of multiple proximal non-cavitated lesions via the application of 38% silver fluoride after placement of orthodontic separators in the permanent dentition in high-caries-risk children.

MATERIALS AND METHODS

The case series describes the management of initial proximal carious lesions using silver fluoride (SF) products in the permanent dentition of two adolescent patients with prior proximal caries progression. Both presented with multiple asymptomatic carious lesions that were identified through the use of bitewing radiographs and classified according to the ADA proximal caries classification system. Using orthodontic separators prior to the planned application of SF, most of the surfaces could then be quickly directly examined to check for surface integrity. Follow-up examinations were conducted clinically and radiographically for at least one year to monitor lesion progression.

RESULTS

None of the 25 enamel lesions (E1/E2) exhibited signs of progression after single SF application, while 2 out of 11 dentine lesions (D1) showed progression and required restorative intervention. The progressed lesions potentially had non-cleansable micro-cavitations that were either clinically undetected or not fully reached with the micro-brush in SF application. Thus, this should have been repeated or combined with SF application via soaked superfloss to potentially achieve better results.

CONCLUSIONS

Single application of 38% silver fluoride directly onto active enamel lesions in juvenile permanent teeth with the prior use of orthodontic separators combined with a caries-risk-specific prevention program appears to be highly effective and should be considered as a viable minimally invasive option for patients and clinicians due to its cost-effectiveness and time efficiency.

Use of Digital Diagnostic Aids for Initial Caries Detection: A Review

The advance in digital diagnostic technologies has significantly facilitated the detection of dental caries. Despite the increase in clinically available digital diagnostic aids for dental caries, there is yet to be a comprehensive summary of all available technology. This review aims to provide an overview of digital diagnostic aids for the clinical detection of dental caries, particularly those at an initial stage. Currently available digital diagnostic aids for caries detection can be classified into four categories according to the initial source of energy, including radiation-based aids, light-based aids, ultrasound-based aids, and electric-based aids. Radiation-based aids use ionizing radiation, normally X-ray, to produce images of dental structures. Radiation-based aids encompass digital bitewing radiography and cone beam computed tomography. Light-based aids employ light or laser to induce signals for the detection of the changes in the carious dental hard tissue. Common light-based aids include digital transillumination and light/laser-induced fluorescence. Ultrasound-based aids detect the signal of ultrasound waves to assess the acoustic impedance of the carious teeth. The ultrasound caries detector is an available ultrasound-based aid. Electric-based aids assess the changes in the electric current conductance or impedance of the teeth with caries. Available electric-based aids include electrical conductance measurement and alternating current impedance spectroscopy. Except for these clinically available digital diagnostic aids, many digital diagnostic aids for caries detection are still under development with promising results in laboratory settings.

Monitoring lesion activity on primary teeth with CP-OCT and SWIR reflectance imaging

OBJECTIVE

The purpose of this study was to use cross polarization optical coherence tomography (CP-OCT) and short wavelength infrared imaging (SWIR) reflectance imaging to monitor changes in the structure and activity of early occlusal caries on primary teeth over a period of 6 months during intervention with fluoride.

METHODS

Participants (n = 29) aged 6-10 each with two suspected active occlusal lesions on primary teeth completed the study. Fluoride varnish was applied to tooth surfaces every 3-months and participants were instructed to brush twice daily with a fluoride toothpaste. Images were acquired using CP-OCT every 3 months for 6 months. SWIR reflectance images were acquired during forced air-drying of the lesions for 30 s at 0 and 6-months.

RESULTS

Most of the 42 lesions appeared initially active at baseline. Only 6 lesions appeared arrested at baseline based on the presence of a highly mineralized transparent surface layer (TSL) in CP-OCT images. At 6 months, 14 of the lesions appeared arrested including the 6 initially arrested lesions and the TSL thickness increased significantly (p < 0.0001). The mean lesion depth (Ld) and the integrated reflectivity over the lesion depth (ΔR) increased significantly (p < 0.05) after 6 months for the 42 lesions analyzed. SWIR reflectance images showed that there was a significantly higher (p < 0.05) delay before changes in intensity were measured for active lesions versus arrested lesions during lesion drying.

CONCLUSION

CP-OCT was able to monitor changes in lesion structure and activity including the formation of a highly mineralized TSL indicative of lesion arrest during nonsurgical intervention. Time-resolved SWIR reflectance imaging also shows that there are differences in the dehydration kinetics between active and arrested lesions. This study demonstrates two independent imaging methods that can be used to monitor changes in lesion activity over time.

Tooth Type Enhanced Transformer for Children Caries Diagnosis on Dental Panoramic Radiographs

The objective of this study was to introduce a novel deep learning technique for more accurate children caries diagnosis on dental panoramic radiographs. Specifically, a swin transformer is introduced, which is compared with the state-of-the-art convolutional neural network (CNN) methods that are widely used for caries diagnosis. A tooth type enhanced swin transformer is further proposed by considering the differences among canine, molar and incisor. Modeling the above differences in swin transformer, the proposed method was expected to mine domain knowledge for more accurate caries diagnosis. To test the proposed method, a children panoramic radiograph database was built and labeled with a total of 6028 teeth. Swin transformer shows better diagnosis performance compared with typical CNN methods, which indicates the usefulness of this new technique for children caries diagnosis on panoramic radiographs. Furthermore, the proposed tooth type enhanced swin transformer outperforms the naive swin transformer with the accuracy, precision, recall, F1 and area-under-the-curve being 0.8557, 0.8832, 0.8317, 0.8567 and 0.9223, respectively. This indicates that the transformer model can be further improved with a consideration of domain knowledge instead of a copy of previous transformer models designed for natural images. Finally, we compare the proposed tooth type enhanced swin transformer with two attending doctors. The proposed method shows higher caries diagnosis accuracy for the first and second primary molars, which may assist dentists in caries diagnosis.

A Novel Deep Learning-Based Approach for Segmentation of Different Type Caries Lesions on Panoramic Radiographs

The study aims to evaluate the diagnostic performance of an artificial intelligence system based on deep learning for the segmentation of occlusal, proximal and cervical caries lesions on panoramic radiographs. The study included 504 anonymous panoramic radiographs obtained from the radiology archive of Inonu University Faculty of Dentistry's Department of Oral and Maxillofacial Radiology from January 2018 to January 2020. This study proposes Dental Caries Detection Network (DCDNet) architecture for dental caries segmentation. The main difference between DCDNet and other segmentation architecture is that the last part of DCDNet contains a Multi-Predicted Output (MPO) structure. In MPO, the final feature map split into three different paths for detecting occlusal, proximal and cervical caries. Extensive experimental analyses were executed to analyze the DCDNet network architecture performance. In these comparison results, while the proposed model achieved an average F1-score of 62.79%, the highest average F1-score of 15.69% was achieved with the state-of-the-art segmentation models. These results show that the proposed artificial intelligence-based model can be one of the indispensable auxiliary tools of dentists in the diagnosis and treatment planning of carious lesions by enabling their detection in different locations with high success.

Current Status and Trends in Research on Caries Diagnosis: A Bibliometric Analysis

There are a wide variety of devices for the detection and diagnosis of caries from the initial stages. The purpose of this study was to perform a bibliometric study on research regarding caries diagnosis by identifying the contributing researchers, organizations, countries or regions, journals, and to provide an analysis of keyword co-occurrence and co-authorship networks. An advanced search was performed in Web of Science (WOS) Core Collection database, using the terms “caries diagno*” and “caries detect*” in the “topic” field, from 2013 to 2021. Bibliometric parameters were extracted using WOS’s analyze results tools and VOSviewer software. A total of 816 documents were identified. Most of them, (61.3%) are included in “Dentistry Oral Surgery & Medicine” category within WOS. The largest scientific production on the subject is observed between 2018 and 2021, with a total of 344 records. The most productive author is Mendes FM, followed by Braga MM. The journal with the most articles published on caries diagnosis is Caries Research, with 55 articles (6.74%). The terms with the highest co-occurrence refer to the validity of diagnostic methods, tools or principles used in diagnosis or general aspects related to caries detection and diagnosis.

Deep Learning for Caries Detection and Classification

Objectives: Deep learning methods have achieved impressive diagnostic performance in the field of radiology. The current study aimed to use deep learning methods to detect caries lesions, classify different radiographic extensions on panoramic films, and compare the classification results with those of expert dentists. Methods: A total of 1160 dental panoramic films were evaluated by three expert dentists. All caries lesions in the films were marked with circles, whose combination was defined as the reference dataset. A training and validation dataset (1071) and a test dataset (89) were then established from the reference dataset. A convolutional neural network, called nnU-Net, was applied to detect caries lesions, and DenseNet121 was applied to classify the lesions according to their depths (dentin lesions in the outer, middle, or inner third D1/2/3 of dentin). The performance of the test dataset in the trained nnU-Net and DenseNet121 models was compared with the results of six expert dentists in terms of the intersection over union (IoU), Dice coefficient, accuracy, precision, recall, negative predictive value (NPV), and F1-score metrics. Results: nnU-Net yielded caries lesion segmentation IoU and Dice coefficient values of 0.785 and 0.663, respectively, and the accuracy and recall rate of nnU-Net were 0.986 and 0.821, respectively. The results of the expert dentists and the neural network were shown to be no different in terms of accuracy, precision, recall, NPV, and F1-score. For caries depth classification, DenseNet121 showed an overall accuracy of 0.957 for D1 lesions, 0.832 for D2 lesions, and 0.863 for D3 lesions. The recall results of the D1/D2/D3 lesions were 0.765, 0.652, and 0.918, respectively. All metric values, including accuracy, precision, recall, NPV, and F1-score values, were proven to be no different from those of the experienced dentists. Conclusion: In detecting and classifying caries lesions on dental panoramic radiographs, the performance of deep learning methods was similar to that of expert dentists. The impact of applying these well-trained neural networks for disease diagnosis and treatment decision making should be explored.

An Intraoral OCT Probe to Enhanced Detection of Approximal Carious Lesions and Assessment of Restorations

Caries, the world's most common chronic disease, remains a major cause of invasive restorative dental treatment. To take advantage of the diagnostic potential of optical coherence tomography (OCT) in contemporary dental prevention and treatment, an intraorally applicable spectral-domain OCT probe has been developed based on an OCT hand-held scanner equipped with a rigid 90°-optics endoscope. The probe was verified in vitro. In vivo, all tooth surfaces could be imaged with the OCT probe, except the vestibular surfaces of third molars and the proximal surface sections of molars within a "blind spot" at a distance greater than 2.5 mm from the tooth surface. Proximal surfaces of 64 posterior teeth of four volunteers were assessed by intraoral OCT, visual-tactile inspection, bitewing radiography and fiber-optic transillumination. The agreement in detecting healthy and carious surfaces varied greatly between OCT and established methods (18.2-94.7%), whereby the established methods could always be supplemented by OCT. Direct and indirect composite and ceramic restorations with inherent imperfections and failures of the tooth-restoration bond were imaged and qualitatively evaluated. The intraoral OCT probe proved to be a powerful technological approach for the non-invasive imaging of healthy and carious hard tooth tissues and gingiva as well as tooth-colored restorations.

Novel bioactive caries-detecting dye solution: Cytotoxicity, antimicrobial activity, scanning electron microscope, and stereomicroscopic analysis in diagnosis of dental caries

Aim

The aim was (1) to study the cytotoxicity of novel Bioactive Caries-detecting Dye solution (BCD) and its antimicrobial activity against Streptococcus mutans, Lactobacillus acidophilus, Actinomyces naeslundii, and Candida albicans and (2) comparative assessment of BCD and Carie-Care for efficient removal of caries (stereomicroscope) and dentin tubule occlusion (scanning electron microscope [SEM]).

Materials and Methods

For BCD cytotoxic study (direct contact method), colorimetric MTT assay, and cell line study(L929 mouse fibroblast NCTC clone 929 strain L) was performed. Xenetix 350, chitosan, nanohydroxyapatite (nHA), BCD, and Carie-Care solutions were subjected to the antimicrobial activity through blood agar well diffusion method, and the minimum inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) were determined. On 20 extracted human carious teeth a comparative pilot study was done for BCD (Group A, n = 10) and Carie-Care (Group B, n = 10), and evaluated visually and radiographically. After mechanical excavation of caries with a spoon excavator, teeth sectioned longitudinally and stereomicroscopically were evaluated (8x–40x) by two observers. The percentage of dentinal tubule occlusion was evaluated with SEM for both solutions. Statistical kappa analysis of agreement was 0.7–0.8 (P < 0.01). Mann–Whitney test ranks and Wilcoxon signed-rank test (P = 0.01) were applied.

Results

Cytotoxicity test revealed BCD to be nontoxic and biocompatible. Antimicrobial tests (zone of inhibition) showed BCD > chitosan > chlorhexidine > Carie-Care > Xenetix 350 > nHA. MIC and MBC values suggested chlorhexidine > BCD > Carie-Care. Stereomicroscopic analysis showed effective mechanical removal of caries in BCD without residual dye in the dentinal tubules as compared to Carie-Care. Dentinal tubule occlusion (SEM analysis) was 80%–85% for BCD and 10% for Carie-Care.

Conclusions

Profound synergistic effect for BCD was observed with advantage of radiographic assessment.

Thermal Imaging of Root Caries In Vivo

Improved methods are needed to assess the structure and activity of lesions on root surfaces in order to improve clinical decision making. Conventional visual and tactile methods for assessing lesion activity are not reliable, and the clinician is often unable to evaluate if the lesion is progressing or has remineralized. An important marker of an arrested lesion is a highly mineralized surface zone that forms when mineral is deposited in the outer layer of the lesion. In vitro studies have shown that a mineralized surface zone influences the kinetics of water evaporation and the surface temperature while drying. Temperature changes can be monitored by measuring the thermal emission with thermal imaging. Studies have also shown that the depth and severity of demineralization and the thickness of the highly mineralized transparent surface zone on arrested lesions can be measured nondestructively with optical coherence tomography (OCT). Thermal imaging at 8-µm to 13-µm wavelengths was completed on 30 test subjects with a suspected active root caries lesion by monitoring thermal emission from the tooth surfaces during 30 s of air drying. Lesions were also evaluated using cross-polarization OCT (CP-OCT) during lesion dehydration to identify transparent surface zones indicative of arrested lesions and determine if shrinkage occurred during drying. The overall thermal emission recorded during drying was significantly different (P < 0.001) when comparing sound tooth surfaces, lesion areas identified as arrested, and lesion areas identified as active, demonstrating that thermal imaging is a promising approach for the clinical assessment of lesion activity on root surfaces. Ten of the lesions in this study had distinct areas with transparent surface zones that were visible in CP-OCT images. Shrinkage was detected with CP-OCT during drying for 12 lesions. This study confirms that these novel approaches for assessing lesion activity on root surfaces can be implemented in vivo.

Spectral characteristics of caries autofluorescence obtained from different locations and caries severities

Dental caries usually occurs at interproximal and occlusal surfaces. The purpose of the present study was to determine if characteristic spectral factors extracted from autofluorescence (AF) spectra are informative regarding caries detection and the determination of caries stage as compared with DIAGNOdent results. AF spectra were obtained from caries lesions of different severities at two locations using a 405 nm laser. Three spectral factors, that is, spectral slope at 550 to 600 nm, spectral area under the curve at 500 to 590 nm and two-peak ratio between 625 and 667 nm, were extracted. The values of three spectral factors linearly decreased as caries progressed. According to micro-CT images, conventional visual and tactile inspections of lesions under or overestimated (25%-65%) caries states, and brown or thickly stained layer on interproximal or occlusal surfaces, respectively, caused misclassifications of caries stage. Of the spectral factors examined, spectral slope and area under curve for interproximal and occlusal surfaces, respectively, were found to be significantly related to caries stage and showed least data overlap. For interproximal and occlusal surfaces, DIAGNOdent readings of different stages overlapped considerably though their mean values were significantly different regardless of stage.

Use of DIAGNOdent and VistaProof in diagnostic of Pre-Cavitated Caries Lesions-A Systematic Review and Meta-Analysis

Objective: To analyse the published evidence of the validity of DIAGNDOdent and VistaProof in diagnosing carious depths in pre-cavitated lesions. Material and methods: A systematic review was carried out after identifying a total of 184 articles, including 27 concerning the qualitative review and a subsequent meta-analysis. The quality of the studies was evaluated by using the QUADAS-2 tool. Results: For DIAGNOdent, the sensitivity value was 0.77, the specificity value was 0.75 and AUC was 0.81 for the global meta-analyses. In relation to subgroups, the values estimated 0.85, 0.76 and 0.86, respectively, for the in vivo group and 0.71, 0.75 and 0.83 for the in vitro group. For VistaProof, sensitivity was 0.81, specificity 0.75 and AUC had a value of 0.80 in the global meta-analysis. For the subgroups, these were considered at 0.75, 0.81 and 0.89, respectively, for the in vivo group and 0.91, 0.74 and 0.76 for the in vitro group. Neither case presented publication bias when analysing the funnel plot, the classic fail-safe number and Egger’s intercept. Conclusion: Both VistaProof and DIAGNOdent are valid as they offer a moderate to high diagnostic effectiveness for dentine depth in pre-cavitated lesions.

High-Frequency Ultrasound Imaging for Examination of Early Dental Caries

The extent of dental tissue destruction during the treatment of white spot lesions (WSLs) increases with the severity of the lesion. If the depth and shape of WSLs can be predicted with a noninvasive diagnostic method before dental caries treatment, more conservative interventions can be planned. Given the superiority of high-frequency ultrasound (HFUS) imaging in observing the internal structures of the body, the present study aimed to verify the possibility of HFUS imaging to examine the depth and shape of WSLs. We prepared tooth samples and developed a biomicroscopic system with a HFUS transducer to obtain images of normal and WSL regions. HFUS images were compared with conventional ultrasound images and micro-computed tomography images. HFUS distinctly differentiated demineralization within WSL and normal regions. WSL depth calculated in the micro-computed tomography image was similar to that in HFUS. This study revealed that HFUS imaging has the potential to detect early dental caries and offer information on the invasion depth of early dental caries quantitatively.

Saliva and biofilm-based diagnostics: a critical review of the literature concerning sialochemistry

There is some evidence to support the use of salivary diagnostics in dentistry.

BACKGROUND AND PURPOSE

The use of saliva as a diagnostic fluid has the potential to shape the role of oral health care professionals in the health care system. While more than a handful of chairside diagnostic tests are available for use by private practitioners, the evidence supporting their use continues to emerge.

METHODS

An electronic search of the literature indexed on the PubMed electronic database was conducted to identify human clinical trials utilizing commercially available salivary diagnostics. Papers meeting the inclusion criteria, and any applicable references were critically appraised following SORT guidelines.

CONCLUSIONS

While the literature concerning salivary analysis is continuously growing, the limited literature that is available doesn't focus on patient oriented health outcomes. This 'infant' literature is focused on validating metrics and identifying biomarkers with diagnostic potential. As such, the evidence level of the literature is graded as level 3. Despite the lower grade, the research in this area shows consistent results, coherent conclusions, and research identifying new biomarkers will provide additional dimensions to salivary diagnostics.

Visual-tactile versus radiographic caries detection agreement in caries-active adults

OBJECTIVES

The study aims to determine a) the extent of agreement between visual-tactile caries examination (VTE) and radiographic examination (RE) in detecting presumptive caries lesions on occlusal and proximal surfaces of posterior teeth of UNC Xylitol for Adult Caries Trial participants; and b) the additional caries diagnostic yield obtained by adding RE to VTE.

METHODS

Data consisted of surface-level visual-tactile and radiographic classification of disease (cavitated and noncavitated caries lesions) or nondisease (sound surfaces). Participants (n = 114, adults with ≥12 erupted teeth and 1-10 caries lesions) received baseline VTE by a trained and calibrated examiner, and had interproximal radiographs obtained within 7 months before or after the VTE. Radiographs were assessed independently by two trained and calibrated examiners masked with respect to VTE results. The diagnostic threshold was surface-level disease/nondisease status. Kappa statistics provided an estimate of VTE-RE agreement on diseased surfaces. The additional diagnostic yield of the RE over VTE was calculated as the additional lesions detected radiographically as a percentage of the total number of lesions detected by VTE.

RESULTS

Four-hundred ninety-four (51 occlusal, 433 proximal) lesions were detected; of these, 81 (2 occlusal, 79 proximal) lesions were detected by both VTE and RE. Kappa statistics were 0.18 (all surfaces), 0.04 (occlusal), and 0.18 (proximal). The additional diagnostic yield was 69 percent (all surfaces), 55 percent (occlusal), and 71 percent (proximal).

CONCLUSIONS

There is poor agreement between VTE and RE to detect caries in posterior teeth of caries-active adults. However, an RE performed within 7 months of a VTE adds caries diagnostic yield in a clinical trial, especially on proximal surfaces.

Restorative treatment thresholds for interproximal primary caries based on radiographic images: findings from the Dental Practice-Based Research Network

This study sought to quantify the depths of proximal caries lesions that lead dentists in regular clinical practice to intervene restoratively, based on hypothetical scenarios that present radiographic images and patient background information, and to identify characteristics associated with restorative intervention in lesions that have penetrated only the enamel surface. This study surveyed dentists from the Dental Practice-Based Research Network (DPBRN) who had reported doing at least some restorative dentistry (n = 901). Dentists were asked to indicate the depth at which they would restore a lesion, based on a series of radiographic images depicting interproximal caries at increasing lesion depths in a mandibular premolar; in addition, the dentists were questioned regarding two caries risk scenarios: one involving a patient with low caries risk and another involving a patient at higher risk. Logistic regression was used to analyze associations between the decision to intervene restoratively and specific dentist, practice, and patient characteristics. Of the 901 DPBRN practitioner-investigators, 500 (56%) completed the survey. For a high caries risk patient, 66% of respondents indicated that they would restore a proximal enamel lesion, while 24% would do so once the lesion had reached into the outer third of the dentin. For a low caries risk patient, 39% of respondents reported that they would restore an enamel lesion, and 54% would do so once the lesion had reached into the outer third of the dentin. In multivariate analyses that accounted for dentist and practice characteristics, dentists in large group practices were less likely to intervene surgically for enamel caries, regardless of patient's caries risk.