A Clinical Study of Caries Diagnosis With a Laser Fluorescence System

Detection Methods for Early Caries Diagnosis: A Systematic Review and Meta-Analysis

The aim was to appraise the evidence on the performance of various means for the detection of incipient caries in vivo. Five databases of published and unpublished research were searched for studies from January 2000 to October 2019. Search terms included "early caries" and "caries detection." Inclusion criteria involved diagnostic test accuracy studies for early caries detection in permanent and primary teeth. A risk-of-bias assessment was performed using the QUADAS-2 tool. We performed the study selection, data extraction, and risk-of-bias assessment in duplicate. The review protocol was a priori registered in the Open Science Framework. Of the initially 22,964 search results, 51 articles were included. For permanent teeth, when histologic examination was considered as the reference for occlusal surfaces, the sensitivity (Se) range appeared high for the DIAGNOdent Pen (DD Pen) at 0.81-0.89, followed by ICDAS-II at 0.62-1, DIAGNOdent (DD) at 0.48-1, and bitewing radiography (BW) at 0-0.29. The corresponding specificity (Sp) range was: DD Pen 0.71-0.8, ICDAS-II 0.5-0.84, DD 0.54-1, and BW 0.96-1. When operative intervention served as the reference for occlusal surfaces, again, the DD means valued the most promising results on Se: DD 0.7-0.96 and DD Pen 0.55-0.90, followed by ICDAS-II 0.25-0.93, and BW 0-0.83. The Sp range was: DD 0.54-1, DD Pen 0.71-1, ICDAS-II 0.44-1, and BW 0.6-1. For approximal surfaces, the Se was: BW 0.75-0.83, DD Pen 0.6, and ICDAS-II 0.54; the Sp was: BW 0.6-0.9, DD Pen 0.2, and ICDAS-II 1. For primary teeth, under the reference of histologic assessment, the Se range for occlusal surfaces was: DD 0.55-1, DD Pen 0.63-1, ICDAS-II 0.42-1, and BW 0.31-0.96; the respective Sp was: DD 0.5-1, DD Pen 0.44-1, ICDAS-II 0.61-1, and BW 0.79-0.98. For approximal surfaces, the Se range was: DD Pen 0.58-0.63, ICDAS-II 0.42-0.55, and BW 0.14-0.71. The corresponding Sp range was: DD Pen 0.85-0.87, ICDAS-II 0.73-0.93, and BW 0.79-0.98. Se and Sp values varied, due to the heterogeneity regarding the setting of individual studies. Evidently, robust conclusions cannot be drawn, and different diagnostic means should be used as adjuncts to clinical examination. In permanent teeth, visual examination may be enhanced by DD on occlusal surfaces and BW on approximal surfaces. In primary teeth, DD Pen may serve as a supplementary tool across all surfaces.

Fluorescence devices for the detection of dental caries

BACKGROUND

Caries is one of the most prevalent and preventable conditions worldwide. If identified early enough then non-invasive techniques can be applied, and therefore this review focusses on early caries involving the enamel surface of the tooth. The cornerstone of caries detection is a visual and tactile dental examination, however alternative methods of detection are available, and these include fluorescence-based devices. There are three categories of fluorescence-based device each primarily defined by the different wavelengths they exploit; we have labelled these groups as red, blue, and green fluorescence. These devices could support the visual examination for the detection and diagnosis of caries at an early stage of decay.

OBJECTIVES

Our primary objectives were to estimate the diagnostic test accuracy of fluorescence-based devices for the detection and diagnosis of enamel caries in children or adults. We planned to investigate the following potential sources of heterogeneity: tooth surface (occlusal, proximal, smooth surface or adjacent to a restoration); single point measurement devices versus imaging or surface assessment devices; and the prevalence of more severe disease in each study sample, at the level of caries into dentine.

SEARCH METHODS

Cochrane Oral Health's Information Specialist undertook a search of the following databases: MEDLINE Ovid (1946 to 30 May 2019); Embase Ovid (1980 to 30 May 2019); US National Institutes of Health Ongoing Trials Register (ClinicalTrials.gov, to 30 May 2019); and the World Health Organization International Clinical Trials Registry Platform (to 30 May 2019). We studied reference lists as well as published systematic review articles.

SELECTION CRITERIA

We included diagnostic accuracy study designs that compared a fluorescence-based device with a reference standard. This included prospective studies that evaluated the diagnostic accuracy of single index tests and studies that directly compared two or more index tests. Studies that explicitly recruited participants with caries into dentine or frank cavitation were excluded.

DATA COLLECTION AND ANALYSIS

Two review authors extracted data independently using a piloted study data extraction form based on the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2). Sensitivity and specificity with 95% confidence intervals (CIs) were reported for each study. This information has been displayed as coupled forest plots and summary receiver operating characteristic (SROC) plots, displaying the sensitivity-specificity points for each study. We estimated diagnostic accuracy using hierarchical summary receiver operating characteristic (HSROC) methods. We reported sensitivities at fixed values of specificity (median 0.78, upper quartile 0.90).

MAIN RESULTS

We included a total of 133 studies, 55 did not report data in the 2 x 2 format and could not be included in the meta-analysis. 79 studies which provided 114 datasets and evaluated 21,283 tooth surfaces were included in the meta-analysis. There was a high risk of bias for the participant selection domain. The index test, reference standard, and flow and timing domains all showed a high proportion of studies to be at low risk of bias. Concerns regarding the applicability of the evidence were high or unclear for all domains, the highest proportion being seen in participant selection. Selective participant recruitment, poorly defined diagnostic thresholds, and in vitro studies being non-generalisable to the clinical scenario of a routine dental examination were the main reasons for these findings. The dominance of in vitro studies also means that the information on how the results of these devices are used to support diagnosis, as opposed to pure detection, was extremely limited. There was substantial variability in the results which could not be explained by the different devices or dentition or other sources of heterogeneity that we investigated. The diagnostic odds ratio (DOR) was 14.12 (95% CI 11.17 to 17.84). The estimated sensitivity, at a fixed median specificity of 0.78, was 0.70 (95% CI 0.64 to 0.75). In a hypothetical cohort of 1000 tooth sites or surfaces, with a prevalence of enamel caries of 57%, obtained from the included studies, the estimated sensitivity of 0.70 and specificity of 0.78 would result in 171 missed tooth sites or surfaces with enamel caries (false negatives) and 95 incorrectly classed as having early caries (false positives). We used meta-regression to compare the accuracy of the different devices for red fluorescence (84 datasets, 14,514 tooth sites), blue fluorescence (21 datasets, 3429 tooth sites), and green fluorescence (9 datasets, 3340 tooth sites) devices. Initially, we allowed threshold, shape, and accuracy to vary according to device type by including covariates in the model. Allowing consistency of shape, removal of the covariates for accuracy had only a negligible effect (Chi2 = 3.91, degrees of freedom (df) = 2, P = 0.14). Despite the relatively large volume of evidence we rated the certainty of the evidence as low, downgraded two levels in total, for risk of bias due to limitations in the design and conduct of the included studies, indirectness arising from the high number of in vitro studies, and inconsistency due to the substantial variability of results.

AUTHORS' CONCLUSIONS

There is considerable variation in the performance of these fluorescence-based devices that could not be explained by the different wavelengths of the devices assessed, participant, or study characteristics. Blue and green fluorescence-based devices appeared to outperform red fluorescence-based devices but this difference was not supported by the results of a formal statistical comparison. The evidence base was considerable, but we were only able to include 79 studies out of 133 in the meta-analysis as estimates of sensitivity or specificity values or both could not be extracted or derived. In terms of applicability, any future studies should be carried out in a clinical setting, where difficulties of caries assessment within the oral cavity include plaque, staining, and restorations. Other considerations include the potential of fluorescence devices to be used in combination with other technologies and comparative diagnostic accuracy studies.

An In Vivo Investigation of Diagnostic Performance of DIAGNOdent Pen and the Canary System for Assessment and Monitoring Enamel Caries under Fissure Sealants

Aim and Objectives

The aim of this study was to evaluate and compare the diagnostic performance of a quantitative light-induced fluorescence (DIAGNOdent pen [DP]) and a photothermal radiometry (Canary System [CS]) for assessment and monitoring occlusal enamel caries under fissure sealants placed on young permanent teeth.

Materials and Methods

Forty-five patients of mean age 9.96 (1.4) years, having at least two occlusal surface sites of non-cavitated lesions (International Caries Detection and Assessment System [ICDAS], 1-3 at baseline), were assigned for this clinical study as per specific inclusion/exclusion criteria. A total of 90 permanent teeth were examined using a visual examination method (ICDAS), a quantitative light-induced fluorescence (DP), and a photothermal radiometry (CS). Teeth were randomly divided into two groups based on the type of fissure sealants: a resin sealant and a glass-ionomer sealant. Sealants were placed over the study sites, and caries assessment was performed with each caries detection method at 3- and 6-month recall appointments. Numerical data were presented as mean, standard deviation, median, and interquartile range values. Qualitative data were presented as frequencies and percentages. Receiver operating characteristic (ROC) curve was constructed to determine the diagnostic accuracy measures of the two modalities and compared using z-statistic. ROC curve analysis was performed with MedCalc software, Ostend, Belgium, version 11.3 for Windows (MedCalc Software). Changes by time in caries progression were analyzed using McNemar test and Cochran Q test. The significance level was set at P ≤ 0.05. Statistical analysis was performed with the IBM Statistical Package for the Social Sciences (SPSS) software for Windows, version 23.0 (IBM, Armonk, New York).

Results

The CS and DP were able to distinguish between sound and carious tissue beneath fully and partially retained sealants at 6-month follow-up with an accuracy of 46.7% and 33.4%, respectively.

Conclusion

The diagnostic performance of the CS and DP are acceptable and can be considered as useful adjunct tools in the clinical evaluation and monitoring the changes in enamel due to lesion progression under fissure sealants. However, in the clinical setting, sensitivity and specificity of these devices may be influenced by the sealant type, thickness, retention, and the differences in the lesion characteristics over time.

Clinical instruments and methods for assessing physical oral health: A systematic review

OBJECTIVE

This study aimed at exploring available clinical instruments and methods for assessing physical oral health, and at identifying those with sufficient diagnostic performance.

METHODS

A systematic literature search was conducted in Embase and MEDLINE. Identified instruments and methods were critically appraised, and quality of diagnostic performance was rated by two independent reviewers as A (sufficient diagnostic performance), B (either sufficient reliability or validity) or C (insufficient quality, or empirical results unsatisfactory and/or inconsistent). For all A-rated instruments and methods, an in-depth literature search was conducted to supplement and verify their effectiveness and accuracy.

RESULTS

A total of 141 instruments and methods were identified. Only 12 methods with sufficient diagnostic performance could be rated as A, 72 were rated as B, and 34 received a C-rating. Further 23 instruments and methods could not be rated due to lack of available information on diagnostic performance. Of all A-rated instruments, six were designed for tooth structure, two for periodontium, one for endodontium and three for temporomandibular joints and muscles.

CONCLUSION

Even though some instruments and methods exhibited good to excellent reliability and validity and can be recommended for research and clinical practice, they do not allow assessing all components of physical oral health. There is a need to identify and define standard instruments, and for components of physical oral health where methods with sufficient diagnostic performance are lacking, further research is required.

[Ex vivo assessment of the potency of optical coherence tomography for the detection of early occlusal caries]

OBJECTIVE

This study aimed to evaluate the potency of optical coherence tomography (OCT) to detect early occlusal caries compared with clinical visual examination.

METHODS

Approximately 97 sites of occlusal fissures on 77 extracted accessional human teeth were scored by three examiners using conventional visual examination and OCT. Results of histological examination on these sites obtained by polarimicroscope served as a gold standard to analyze the sensitivity (SE), specificity (SP), positive predictive value (PPV), and negative predictive value (NPV). Results of the area under receiver operating characteristic (ROC) curve (AUC) by visual examination and OCT were also analyzed. The Spearman's rank correlation coefficient with histology and the inter-examiner reliability were compared.

RESULTS

For sites of enamel demineralization limited to the outer 1/2 of the enamel layer, the detection rate of OCT (14/25) was obviously higher than that of the clinical and visual examination (3/25). SE, SP, PPV and NPV of OCT during diagnosis of the early occlusal caries (0.83, 0.64, 0.87 and 0.57) were higher than that of the visual examination (0.79, 0.60, 0.85 and 0.50). AUC (95%CI) of OCT and the visual examination were 0.737 (0.569-0.822) and 0.696 (0.614-0.859), respectively. No statistically significant difference was observed between the results. Results of OCT correlated well with histology (r=0.559, P<0.05). The inter-examiner reliability of OCT was medium.

CONCLUSIONS

OCT can accurately detect early occlusal lesions atraumatically with high sensitivity and effectiveness. OCT exhibits the potential of auxiliary clinical diagnosis enhancing detection rate and finally implementing early diagnosis and early intervention of early occlusal lesions in clinical practice.

Predictive research methods of enamel and dentine for initial caries detection

Currently, various research methods of enamel and dentine for precautionary diagnostics of initial caries forms are developed; however, the vast majority of these do not provide objective criteria of caries diagnostics or are very difficult to perform. Therefore, the search of diagnostics and enamel research methods, which will allow predicting caries emergence and to carry out personalised prevention of this pathology, is necessary. In this review, modern diagnostic methods that allow understanding the main aspects of caries process, assess the risk of its development, and also suggest the possibility of emergency prevention of caries progression in the nearest future are presented.

Comparison between a laser fluorescence device and visual examination in the detection of occlusal caries in children

Occlusal surfaces of molars are especially susceptible to the development of caries due to the features, such as pits and deep fissures, of their anatomical structure.

AIM

To evaluate the efficiency of DIAGNOdent laser fluorescence measurements in comparison with visual examination for occlusal caries detection for first permanent molars in children.

METHODS

The study involved 156 permanent molar teeth in 40 children aged 7-12 years. A relatively new technology, the fluorescence laser DIAGNOdent pen, was used for detecting and diagnosing caries on the occlusal surfaces of molars. The visual examination of fissures was based on the Ekstrand classification system.

RESULTS

The results showed a strong relationship between examination with the DIAGNOdent and visual inspection. DIAGNOdent's sensitivity and specificity were 97% and 52%, respectively, indicating that the laser fluorescence DIAGNOdent pen is a reproducible and accurate diagnostic tool that may be very helpful in conjunction with visual examination in the detection of occlusal caries in permanent molars in children.

There are no clearly superior methods for diagnosing, predicting, and noninvasively treating dental caries

SELECTION CRITERIA

To be included in the systematic review, all articles were required to meet predetermined criteria: the results of the studies should be relevant to the questions posed by the project, ie, have appropriate outcome measures and an appropriate follow-up period and study design.

KEY STUDY FACTOR

With respect to diagnosis, the efficacy of the various methods was compared with reference methods that included studies of extracted teeth. For prediction, the material comprised mainly prospective studies, where the reliability of risk assessment could be evaluated. With respect to treatment of early caries lesions, it was a requirement for inclusion that the study had a control group.

MAIN OUTCOME MEASURE

For caries detection of accessible surfaces, visual-tactile testing was used. Radiographic diagnosis was used for approximal surfaces. For caries risk prediction, modeling was used to determine the influence of specific variables (eg, sugar intake). For noninvasive treatment assessment, size of lesion growth or shrinkage after treatment was used.

MAIN RESULTS

Caries detection: Visual-tactile detection for accessible surfaces carried the best, but far from optimal, accuracy. Although specificity tends to be high with this method, sensitivity is low. Caries risk prediction: Streptococcus mutans count, salivary Lactobacillus count, salivary buffering capacity, visible plaque levels, and sugar intake have low accuracy. The best, but still far from optimal, predictor was past caries history. Noninvasive methods of caries treatment: Too few studies exist for meaningful analysis.

CONCLUSIONS

(1) Past caries is the best predictor of future caries. (2) A combination of visual-tactile and radiographic examination is better than either method alone. (3) There is insufficient evidence to support noninvasive treatment of early caries. STUDY OBJECTIVE AND METHODS: To perform a systematic review of published literature to (1) determine the evidence for the effectiveness of different methods (visual-tactile versus radiographic) for detecting caries; (2) identify the most prescient predictors of dental caries; and (3) evaluate the evidence supporting the use of noninvasive methods for the treatment of caries, particularly early caries.

MAIN RESULTS AND CONCLUSIONS

With regard to the questions posed by the study team: (1) Past caries is the best predictor of future caries; (2) a combination of visual- tactile and radiographic examination is better than either method alone; and (3) there is insufficient evidence to support noninvasive treatment of early caries.