Evaluation of residual dentin thickness using quantitative light-induced fluorescence technology.

This study aimed to determine whether a correlation exists between residual dentin thickness and quantitative light-induced fluorescence (QLF) values and, if so, to analyze its tendencies. Forty extracted sound human molars were assigned to filled and unfilled groups. The teeth were submerged in a mold with clear acrylic resin. Red utility wax was inserted into the pulp chamber space in the filled group to simulate vital pulp. The specimen was sectioned longitudinally to observe the inside of the pulp space. The samples were cut horizontally from the highest point of the pulp space 2 mm apart. QLF images were then taken of 2 mm, 1 mm, and 0.5 mm samples using the QLF-D Biluminator™ 2 + system. Three operators independently evaluated the QLF images, and the statistical analysis was conducted using one-way analysis of variance, Pearson correlation coefficients, and intraclass correlation coefficients. In the filled group, the mean ΔF values for residual dentin thicknesses of 2 mm, 1 mm, and 0.5 mm were - 3.22, - 7.84, and - 11.52, respectively. In the unfilled group, the mean ΔF values were 0, - 6.90, and - 10.14, respectively. A positive correlation was found between residual dentin thickness and ΔF values (P < 0.05). The intraclass correlation coefficients for observations made by the three operators for the filled and unfilled groups were 0.831 and 0.917, respectively (P < 0.05). In conclusion, residual dentin thickness and ΔF values were significantly correlated and had a highly positive correlation regardless of the QLF device operator.

Caries lesions diagnosis with deep convolutional neural network in intraoral QLF images by handheld device.

OBJECTIVES: This study investigated the effectiveness of a deep convolutional neural network (CNN) in diagnosing and staging caries lesions in quantitative light-induced fluorescence (QLF) images taken by a self-manufactured handheld device. METHODS: A small toothbrush-like device consisting of a 400 nm UV light-emitting lamp with a 470 nm filter was manufactured for intraoral imaging. A total of 133 cases with 9,478 QLF images of teeth were included for caries lesion evaluation using a CNN model. The database was divided into development, validation, and testing cohorts at a 7:2:1 ratio. The accuracy, sensitivity, specificity, positive predictive value, negative predictive value, and area under the receiver operating characteristic curve (AUC) were calculated for model performance. RESULTS: The overall caries prevalence was 19.59%. The CNN model achieved an AUC of 0.88, an accuracy of 0.88, a specificity of 0.94, and a sensitivity of 0.64 in the validation cohort. They achieved an overall accuracy of 0.92, a sensitivity of 0.95 and a specificity of 0.55 in the testing cohort. The model can distinguish different stages of caries well, with the best performance in detecting deep caries followed by intermediate and superficial lesions. CONCLUSIONS: Caries lesions have typical characteristics in QLF images and can be detected by CNNs. A QLF-based device with CNNs can assist in caries screening in the clinic or at home. TRIAL REGISTRATION: The clinical trial was registered in the Chinese Clinical Trial Registry (No. ChiCTR2300073487, Date: 12/07/2023).

Correlation of quantitative light-induced fluorescence and qualitative visual rating in infiltrated post-orthodontic white spot lesions.

OBJECTIVES: The aim of this prospective, clinical single-centre study was to evaluate the masking efficacy of post-orthodontic resin infiltration after 12-month follow-up and correlate quantitative and qualitative outcome measures. METHODS: Patients with completed fixed orthodontic treatment and the presence of one or more vestibular active non-cavitated white spot lesion/s (WSL) [ICDAS 1 or 2 (International Caries Detection and Assessment System)] were provided with resin infiltration 3-12 months after bracket removal. All patients (n = 31) participating before (t0) intervention were invited again and examined after 12 months (t2). Enamel demineralization was scored using quantitative light-induced fluorescence [QLF (DeltaF[flourescence], DeltaQ[lesion volume], White Spot Area)] and qualitative visual rating [11-point Likert-scale from 0 (no lesions visible on any tooth) to 10 (all teeth affected on the entire vestibular surface)]. RESULTS: In 17 patients (7 female and 10 male) 112 WSL (ICDAS 1: n = 1; ICDAS 2: n = 111) in 112 teeth were (re)examined. Before treatment (t0) a significant, weak (DeltaF), and moderate (DeltaQ, White Spot Area) correlation was observed between the quantitative and the qualitative rating (P < 0.002) [median DeltaF: -7.31 (-10.4/-6.58)%; DeltaQ:-2.25 (-10.8/-0.41)% mm2; White Spot Area: 0.34 (0.05/1.16) mm2; visual rating:3.7 ± 1.2]. Resin infiltration led to significantly increased fluorescence and decreased visual scores (P < 0.001) 7 days (t1) and 12 months (t2) after treatment. No significant changes based on DeltaF [-6.55 (-7.29/-6.08)%] and on visual ratings [1.0 ± 1.0] were observed between t1 and t2 (P = 1.000). After 7 days (t1) the correlation between the quantitative and the qualitative ratings remained significant, weak to moderate (P < 0.002). After 12 months (t2) the correlation was (non-)significant and weak for DeltaF, DeltaQ, and White Spot Area (P ≤ 0.097). LIMITATIONS: Since the overall masking efficacy of resin infiltration has been shown previously, an untreated control group was omitted. CONCLUSIONS: When assessing the masking efficacy of infiltrated post-orthodontic WSL only a weak to moderate correlation was found between QLF values and visual ratings. Furthermore, over time this correlation decreased. Thus, it remains unclear if QLF is a viable method to assess and quantify infiltrated post-orthodontic WSL over time. TRIAL REGISTRATION: German Clinical Trials Register (DRKS-ID:DRKS00005067).

Tooth caries classification with quantitative light-induced fluorescence (QLF) images using convolutional neural network for permanent teeth in vivo.

BACKGROUND: Owing to the remarkable advancements of artificial intelligence (AI) applications, AI-based detection of dental caries is continuously improving. We evaluated the efficacy of the detection of dental caries with quantitative light-induced fluorescence (QLF) images using a convolutional neural network (CNN) model. METHODS: Overall, 2814 QLF intraoral images were obtained from 606 participants at a dental clinic using Qraypen C® (QC, AIOBIO, Seoul, Republic of Korea) from October 2020 to October 2022. These images included all the types of permanent teeth of which surfaces were smooth or occlusal. Dataset were randomly assigned to the training (56.0%), validation (14.0%), and test (30.0%) subsets of the dataset for caries classification. Moreover, masked images for teeth area were manually prepared to evaluate the segmentation efficacy. To compare diagnostic performance for caries classification according to the types of teeth, the dataset was further classified into the premolar (1,143 images) and molar (1,441 images) groups. As the CNN model, Xception was applied. RESULTS: Using the original QLF images, the performance of the classification algorithm was relatively good showing 83.2% of accuracy, 85.6% of precision, and 86.9% of sensitivity. After applying the segmentation process for the tooth area, all the performance indics including 85.6% of accuracy, 88.9% of precision, and 86.9% of sensitivity were improved. However, the performance indices of each type of teeth (both premolar and molar) were similar to those for all teeth. CONCLUSION: The application of AI to QLF images for caries classification demonstrated a good performance regardless of teeth type among posterior teeth. Additionally, tooth area segmentation through background elimination from QLF images exhibited a better performance.

Arrest of root caries with an adjuvant chlorhexidine-fluoride varnish over a 12-months observation period: a QLF-analyzed, placebo-controlled, randomized, clinical trial (RCT).

This study aimed at evaluating the effectiveness of an adjuvant chlorhexidine-fluoride varnish (Cervitec F) for prevention and arrest of root caries on elderly participants using quantitative light-induced fluorescence (QLF). 23 participants with two or three non-cavitated root carious lesions were included and assigned to three groups of different varnishes (CF: Cervitec F, P: placebo, DP: Duraphate). Agents were applied once to root surface at baseline and in follow-up after 3, 6 and 9 months. The lesions were assessed clinically and with QLF. QLF-images were analyzed regarding fluorescence loss (ΔF), lesion volume (ΔQ) and bacterial activity (ΔR) before (t0), after 14 days (t1), 6- (t2) and 12-months (t3). CF showed a significant difference between t0 and t3: ∆F (- 12.51 [15.41] vs. - 7.80 [16.72], p = 0.012), ∆Q (- 2339.97 (20,898.30) vs. - 751.82 (5725.35), p < 0.001), ∆R (23.80 [41.70] vs. 7.07 [37.50], p = 0.006). Independently of the varnish application, preventive care seems positively influence the root caries progress. Although within CF group the strongest effect was observed, no superiority of a specific varnish application was confirmed over a 12-months QLF observation period. Extra topical fluoride can help remineralise dentin lesions and QLF can be used as a measurement method to determine changes in the dentin lesions.

High-throughput field phenotyping reveals genetic variation in photosynthetic traits in durum wheat under drought.

Chlorophyll fluorescence (ChlF) is a powerful non-invasive technique for probing photosynthesis. Although proposed as a method for drought tolerance screening, ChlF has not yet been fully adopted in physiological breeding, mainly due to limitations in high-throughput field phenotyping capabilities. The light-induced fluorescence transient (LIFT) sensor has recently been shown to reliably provide active ChlF data for rapid and remote characterisation of plant photosynthetic performance. We used the LIFT sensor to quantify photosynthesis traits across time in a large panel of durum wheat genotypes subjected to a progressive drought in replicated field trials over two growing seasons. The photosynthetic performance was measured at the canopy level by means of the operating efficiency of Photosystem II ( Fq'/Fm' ) and the kinetics of electron transport measured by reoxidation rates ( Fr1' and Fr2' ). Short- and long-term changes in ChlF traits were found in response to soil water availability and due to interactions with weather fluctuations. In mild drought, Fq'/Fm' and Fr2' were little affected, while Fr1' was consistently accelerated in water-limited compared to well-watered plants, increasingly so with rising vapour pressure deficit. This high-throughput approach allowed assessment of the native genetic diversity in ChlF traits while considering the diurnal dynamics of photosynthesis.

Evaluation of Periodontal Risk Factors with Quantitative Light-Induced Fluorescence Based Fluorescent Plaque Index, in Comparison to Radiographic and Oral Health Habit Scoring: A Retrospective Case Study.

The aim of this study was to evaluate periodontal risk factors with oral health habits and fluorescent plaque index (FPI) using quantitative light-induced fluorescence (QLF) images, and to evaluate their effect on the degree of radiographic bone loss (RBL). Selected were 276 patients over 19 years of age to complete the questionnaire for oral health habit and take QLF images, periapical and panoramic radiographs. Oral health habit score, age, and sex showed a statistically significant correlation with FPI. FPI showed a lower value as the oral health habit score increased and the age decreased. Moreover, females showed lower FPI values than did males. RBL showed a statistically significant positive correlation with age but did not show any correlation with oral health habit scores and sex. There was no correlation between FPI and RBL. The results of this study suggest that the clinical use of QLF allows plaque detection by non-invasive procedures and can aid in a more objective estimation for oral hygiene status.

Detection of Dental Caries and Cracks with Quantitative Light-Induced Fluorescence in Comparison to Radiographic and Visual Examination: A Retrospective Case Study.

The aim of this study was to present an optimal diagnostic protocol by comparing and analyzing a conventional examination and the quantitative light-induced fluorescence (QLF) technique. Selected were 297 teeth of 153 patients to take QLF images and bitewing radiographs. Occlusal dental caries, proximal dental caries and cracks were evaluated and scored using QLF, X-ray and/or visual criteria. The sensitivity, specificity, and area under the curve (AUC) of a receiver operating characteristic analysis were calculated. Two fluorescence parameters (|ΔFmax| and ΔRmax) were utilized to evaluate the fluorescence pattern according to the severity of lesions based on QLF or X-ray criteria. QLF showed higher scores for detecting occlusal dental caries and cracks than the conventional method. ΔRmax increased more clearly than ΔFmax did with occlusal dental caries. The |ΔFmax| values of occlusal dental caries, proximal dental caries and cracks showed good AUC levels (0.84, 0.81 and 0.83, respectively). The ΔRmax of occlusal dental caries showed the highest AUC (0.91) and the ΔRmax of proximal dental caries showed a fail level (0.59) compared to bitewing radiographs. The QLF image could visualize and estimate the degree of occlusal dental caries or cracks. Consequently, the QLF technique may be an adjunct tool to conventional methods for the detection of occlusal caries and peripheral cracks.

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.

ANTECEDENTES: La caries es una de las afecciones más frecuentes y prevenibles en todo el mundo. Si se identifican con suficiente antelación, se pueden aplicar técnicas no invasivas y, por lo tanto, esta revisión se centra en las caries tempranas que afectan la superficie del esmalte del diente. La piedra angular de la detección de la caries es una exploración dental visual y táctil; sin embargo, existen métodos alternativos de detección, entre los que se incluyen los dispositivos basados en la fluorescencia. Hay tres categorías de dispositivos basados en la fluorescencia, cada una de ellas definida principalmente por las diferentes longitudes de onda que utilizan; estos grupos se han llamado fluorescencia roja, azul y verde. Estos dispositivos podrían apoyar la exploración visual para la detección y el diagnóstico de la caries en una etapa temprana de descomposición. OBJETIVOS: Los objetivos principales fueron determinar la exactitud de la prueba diagnóstica de dispositivos basados en la fluorescencia para la detección y el diagnóstico de la caries del esmalte en niños o adultos. Se planificó investigar las siguientes fuentes potenciales de heterogeneidad: superficie dental (oclusal, proximal, superficie lisa o adyacente a una restauración); dispositivos de medición de punto único frente a dispositivos de imagen o de evaluación de superficie; y la prevalencia de enfermedades más graves en cada muestra de estudio, a nivel de caries en la dentina. MÉTODOS DE BÚSQUEDA: El documentalista del Grupo Cochrane de Salud Oral (Cochrane Oral Health Group) realizó una búsqueda en las siguientes bases de datos: MEDLINE Ovid (1946 al 30 de mayo de 2019); Embase Ovid (1980 al 30 de mayo de 2019); Registro de ensayos en curso de los Institutos Nacionales de Salud de los Estados Unidos (ClinicalTrials.gov, hasta el 30 de mayo de 2019); y la Plataforma de Registro Internacional de Ensayos Clínicos de la Organización Mundial de la Salud (hasta el 30 de mayo de 2019). Se estudiaron las listas de referencias y las revisiones sistemáticas publicadas. CRITERIOS DE SELECCIÓN: Se incluyeron diseños de estudios de exactitud diagnóstica que compararon un dispositivo basado en la fluorescencia con un estándar de referencia. Esto incluyó estudios prospectivos que evaluaron la exactitud diagnóstica de una única prueba índice y estudios que compararon directamente dos o más pruebas índice. Se excluyeron los estudios que reclutaron explícitamente a participantes con caries en la dentina o en la cavitación franca. OBTENCIÓN Y ANÁLISIS DE LOS DATOS: Dos autores de la revisión extrajeron los datos de forma independiente mediante un formulario de extracción de datos de estudios piloto basado en la Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS­2). De cada estudio se informaron la sensibilidad y la especificidad con intervalos de confianza (IC) del 95%. Esta información se ha presentado en forma de diagramas de bosque (forest plot) emparejados y gráficos de curva resumen de rendimiento diagnóstico (SROC), que muestran los puntos de sensibilidad­especificidad de cada estudio. La exactitud diagnóstica se calculó mediante métodos de modelo jerárquico de curva resumen de rendimiento diagnóstico (HSROC). Se informaron sensibilidades a valores fijos de especificidad (mediana 0,78, cuartil superior 0,90). RESULTADOS PRINCIPALES: Se incluyeron un total de 133 estudios, 55 no informaron los datos en el formato 2 x 2 y no se pudieron incluir en el metanálisis. En el metanálisis se incluyeron 79 estudios que proporcionaron 114 conjuntos de datos y evaluaron 21 283 superficies dentales. Hubo alto riesgo de sesgo en el dominio de selección de los participantes. La prueba índice, el estándar de referencia y los dominios de flujo y tiempo mostraron que una alta proporción de los estudios tenían un bajo riesgo de sesgo. Las preocupaciones relacionadas con la aplicabilidad de la evidencia fueron altas o poco claras en todos los dominios, y la mayor proporción se observó en la selección de los participantes. El reclutamiento selectivo de los participantes, los umbrales diagnósticos mal definidos y el hecho de que los estudios in vitro no se puedan generalizar al escenario clínico de una exploración dental de rutina fueron las principales razones de estos hallazgos. El predominio de los estudios in vitro también hizo que la información sobre la forma en que se utilizan los resultados de esos dispositivos para apoyar el diagnóstico, en contraposición con la detección pura, fuera muy limitada. Hubo una variabilidad significativa en los resultados que no se pudo explicar por los diferentes dispositivos o dentición u otras fuentes de heterogeneidad que se investigaron. El odds ratio diagnóstico (ORD) fue 14,12 (IC del 95%: 11,17 a 17,84). La sensibilidad estimada, con una especificidad media fija de 0,78, fue 0,70 (IC del 95%: 0,64 a 0,75). En una cohorte hipotética de 1000 puntos o superficies dentales, con una prevalencia de caries del esmalte del 57%, obtenida de los estudios incluidos, la sensibilidad estimada de 0,70 y la especificidad de 0,78 daría lugar a 171 puntos o superficies dentales con caries del esmalte no detectados (falsos negativos) y 95 incorrectamente considerados con caries temprana (falsos positivos). Se utilizó la metarregresión para comparar la exactitud de los diferentes dispositivos para la fluorescencia roja (84 conjuntos de datos, 14 514 puntos dentales), la fluorescencia azul (21 conjuntos de datos, 3429 puntos dentales), y la fluorescencia verde (nueve conjuntos de datos, 3340 puntos dentales). Inicialmente, se permitió que el umbral, la forma y la exactitud variaran según el tipo de dispositivo, incluyendo covariables en el modelo. Permitiendo la homogeneidad de la forma, la eliminación de las covariables para la exactitud tuvo sólo un efecto insignificante (Ji2 = 3,91; grados de libertad [gl] = 2; p = 0,14). A pesar del volumen relativamente grande de evidencia, la certeza de las mismas se consideró baja, disminuyendo dos niveles en total, por el riesgo de sesgo debido a las limitaciones en el diseño y la realización de los estudios incluidos, los hallazgos indirectos derivados del elevado número de estudios in vitro y la incoherencia debida a la considerable variabilidad de los resultados. CONCLUSIONES DE LOS AUTORES: Existe una considerable variación en la ejecución de estos dispositivos basados en la fluorescencia que no se pudo explicar por las diferentes longitudes de onda de los dispositivos evaluados, los participantes ni las características de los estudios. Los dispositivos basados en la fluorescencia azul y verde parecieron superar a los basados en la fluorescencia roja, pero esta diferencia no estuvo respaldada por los resultados de una comparación estadística formal. La base de evidencia fue considerable, pero sólo fue posible incluir 79 estudios de 133 en el metanálisis, ya que no se pudieron extraer o derivar las estimaciones de los valores de sensibilidad o especificidad o ambos. En cuanto a la aplicabilidad, todo estudio futuro se debería realizar en un ámbito clínico, en el que las dificultades de la evaluación de la caries dentro de la cavidad oral incluyen la placa, la tinción y las restauraciones. Otras consideraciones son el potencial de los dispositivos de fluorescencia para ser utilizados en combinación con otras tecnologías y estudios comparativos de exactitud diagnóstica.

Monitoring enamel caries on resin-treated occlusal surfaces using quantitative light-induced fluorescence: an in vitro study.

The aim of this study is to evaluate the ability of quantitative light-induced fluorescence (QLF) to monitor enamel caries lesions of different severity stages located on the occlusal surfaces of permanent teeth before and after treatment with resin infiltrant. Sixty extracted permanent teeth had one occlusal site selected and were categorized according to the International Caries Detection and Assessment System (ICDAS) criteria. The teeth were divided into three groups (n = 20): ICDAS 1, ICDAS 2, and ICDAS 3. The teeth were assessed by a trained examiner using QLF in two phases: (A) before and (B) after treatment with resin infiltrant. The caries lesions were evaluated using the following QLF parameters: area (mm2); ΔF, fluorescence loss (%); and ΔQ, fluorescence loss integrated over the lesion area (%*mm2). The resin infiltrant (Icon™) was applied on the occlusal surface following the manufacturer's recommendations. The teeth were then sectioned and prepared for polarized light microscopy analysis. The penetration of resin infiltrant was measured with ImageJ. The groups showed a statistically significant difference in all QLF parameters before and after caries infiltration, with the reduction of fluorescence values posttreatment (p < 0.05). Infiltrant penetration was observed in all groups, with a statistical difference between all groups (p < 0.05). The reduction in QLF parameters after resin infiltration suggests that QLF is able to monitor enamel caries lesions of different severity stages located on the occlusal surfaces of permanent teeth before and after treatment with resin infiltrant.

Enamel demineralization during clear aligner orthodontic treatment compared with fixed appliance therapy, evaluated with quantitative light-induced fluorescence: A randomized clinical trial.

INTRODUCTION: The objective of this prospective randomized clinical trial was to investigate the relationship between clear aligner (CA) therapy and the development of white spot lesions and compare it with orthodontic fixed appliance (FA) therapy. METHODS: This was a prospective randomized clinical trial. The setting was the postgraduate orthodontic clinic at Jordan University of Science and Technology. A total of 49 patients (39 female, 10 male; mean age ± standard deviation, 21.25 ± 3 years) who required orthodontic treatment with either FAs or CAs were randomly allocated into 1 of 2 study groups. Eligibility criteria included healthy patients of both sexes (age range 17-24 years), Class I malocclusion with mild-to-moderate crowding (≤5 mm), nonextraction treatment plan, and optimum oral hygiene before treatment as determined by clinical examination. The participants were randomly assigned to a study group according to a simple randomization method using a coin toss by the patient; the text or tail side of the coin indicated treatment with CA (group 1), and the head side of the coin indicated orthodontic treatment with FA (group 2). Blinding was applicable for outcome assessment only. CA therapy was performed for group 1 and FA for group 2. Quantitative light-induced fluorescence (QLF) images were taken before treatment (T0) and 3 months later (T1). The QLF images were then analyzed to assess the research outcomes. The main outcome was the mean amount of fluorescence loss (ΔF). Number of newly developed lesions, deepest point in the lesion (ΔFMax), lesion area (pixels), and plaque surface area (ΔR30) were measured as secondary outcomes. Descriptive statistics and comparison within and between groups were calculated. RESULTS: In total, 42 of the 49 participants recruited completed the study (19 in the CA group and 23 in the FA group). The mean amount of fluorescence loss was 0.4% for the CA group (P = 0.283) and 1.2% for the FA group (P = 0.013). The difference between the 2 groups was significant (confidence interval [CI], -1.8 to -0.4; P = 0.002). The mean increase in lesion area was 82.2 pixels for the CA group (P <0.001) and 9.3 pixels for the FA group (P = 0.225). The difference between the 2 groups was significant (CI, -117 to -75.0; P <0.001). ΔR30 was 1.2% for the CA group and 10.9% for the FA group (CI, 6.847-12.479; P <0.001). The number of newly developed lesions in the CA group was 6 lesions/patient and 8.25 in the FA group (P = 0.039). No serious harm on the oral health of the participants in the 2 study groups was observed other than mild gingivitis associated with plaque accumulation. No serious harm was reported by any of the participants. CONCLUSIONS: Orthodontic treatment with CAs and FAs caused enamel demineralization. The CA group developed larger but shallower white spot lesions, whereas the FA group developed more new lesions with greater severity, but they were smaller in area. More plaque accumulation was found in the FA group compared with the CA group. REGISTRATION: NCT04107012. PROTOCOL: The protocol was published after trial commencement.

A comparative assessment of orthodontic treatment outcomes using the quantitative light-induced fluorescence (QLF) method between direct bonding and indirect bonding techniques in adolescents: a single-centre, single-blind randomized controlled trial.

INTRODUCTION: The aim of this two-arm parallel trial was to evaluate enamel demineralization in fixed orthodontic treatment using an indirect bonding technique in comparison to a direct bonding technique by the quantitative light-induced fluorescence (QLF) method. DESIGN, SETTINGS AND PARTICIPANTS: Fifty-six patients who needed fixed orthodontic treatment were randomly separated into either the direct bonding group or the indirect bonding group. The presence and extent of lesions on the buccal surfaces of all teeth, except the molar teeth, were assessed. The percentage of fluorescence loss (ΔF and ΔFmax), the degree of demineralization (ΔQ) and lesion area (WS area) were determined using the system's software. The data were analysed with the Wilcoxon signed-rank and Mann-Whitney U-tests (P < 0.05). INTERVENTIONS: Treatment with a direct bonding or an indirect bonding technique. RESULTS: This study was completed with 25 patients in the indirect bonding group (12 females, 13 males; mean age: 15.42 ± 1.71 years) and 26 patients in the direct bonding group (12 females, 14 males; mean age: 14.73 ± 1.65 years). In the indirect bonding technique, a few teeth (especially mandibular left canine: 50.45 ± 93.48; 95% confidence interval: -12.35 and 113.26) were found to develop significant white spot lesion (WSL) formation (P < 0.05). However, the number of teeth with demineralization was higher in the direct bonding group (P < 0.05). CONCLUSION: The bonding procedures used in the indirect bonding technique contribute to reducing the degree of WSL formation. Further, the use of flowable composite adhesives in this bonding process is more effective at reducing the appearance of WSLs than in cases where conventional composite adhesives are used. LIMITATIONS: The limitation of our trial may be the small sample size and the short follow-up time for the patients. HARMS: No harms were detected during the study. PROTOCOL: The protocol was not published before trial commencement. REGISTRATION: This trial was registered post hoc at 'Clinical Trials' (http://www.clinicaltrials.gov), registration number (ID): NCT03738839.

Comparison of dental plaque reduction after use of electric toothbrushes with and without QLF-D-applied plaque visualization: a 1-week randomized controlled trial.

BACKGROUND: To evaluate the efficacy of a newly developed electric toothbrush in reducing dental plaque via a quantitative light-induced fluorescence-digital (QLF-D)-applied visualisation system in the brush head. METHODS: Participants included 20 adults aged 19 to 28 years. Participants were randomly assigned either (i) an electric toothbrush with a monitor to visualise red-fluorescent dental plaque via a camera built into the brush head (monitor usage group, n = 10) or (ii) an electric toothbrush without a monitor (monitor-non-use group, n = 10). The amount of dental plaque was assessed by personal hygiene performance (PHP) at baseline and 1 week later. RESULTS: In the monitor-usage group, PHP score was significantly lower at the 1-week follow-up than at baseline (6 vs 16; range, 0-12 vs 13-21; P = 0.029). This change was not observed in the monitor-non-use group (14 vs 13; range, 6-21 vs 2-26; P = 0.778). After 1 week, the change in PHP scores in the monitor usage group was significantly greater than that in the monitor non-use group (- 10 vs 0; range, - 21 to 9 vs - 8 to 16; P = 0.021). CONCLUSIONS: Our results clearly demonstrate that brushing teeth while looking at a monitor that depicts red-autofluorescent dental plaque via application of QLF-D improved the efficacy of dental-plaque removal relative to brushing teeth without a monitor. TRIAL REGISTRATION: Trial registration number: UMIN000033699. Name of registry: Study on effect of new devise for oral care on dental plaque clearance. Date of registration: 8th September 2018. Status of registration: Completed.

Methods of assessment of early dentine erosion: a review.

Dentine erosion is an increasingly recognised problem, especially in aging population, and various methods have been utilised for its assessment. This narrative review was planned to summarise the methods for the assessment of the early stages of dentine erosion. Relevant original articles published in the English language from 2013 to 2017 were reviewed. Laboratory techniques and methods with in vivo potential were separately studied. It is evident that the assessment of early dentine erosion is complex and requires a combination of methods. For clinical evaluation, chemical analysis and optical methods show great potential but are in need of more validation.

The reproducibility of assessment of white spot lesions adjacent to orthodontic brackets, with a quantitative light induced fluorescence digital camera at different rotations of teeth - an in vitro study.

BACKGROUND: A quantitative light-induced fluorescence digital (QLF-D) camera is able to assess demineralizations adjacent to orthodontic brackets. Rotations of teeth during and the presence of the orthodontic appliances may influence the longitudinal follow-up of such lesions over time. METHODS: Brackets were bonded on extracted teeth: 54 incisors and 31 canines. Demineralizations were formed in vitro directly cervical of the bracket. Images were captured using a QLF-D camera mounted on an optical bench, equipped with a goniometer on a turntable. The teeth were placed in the goniometer simulating buccolingual rotation (0°, 10°, 20°), the turn-table was used for mesiodistal rotations (0°, 10°, 20°). Standardized QLF-D images were made before (with and without a wire) and after debonding at combinations of aforementioned angles of rotation. The image after debonding at 0° buccolingual and 0° mesiodistal rotation served as a control. RESULTS: The presence of a bracket resulted in a significantly higher fluorescence loss, yet a smaller lesion area (p < 0.05) in comparison to the control. A significant higher fluorescence loss was seen for rotations towards lingual relative to the 0° buccolingual and 0° mesiodistal rotation, while the effect was less explicit towards buccal. CONCLUSIONS: Fluorescence loss and lesion size are influenced by the angle of rotation under which the demineralization is photographed. The full extent of demineralizations is only apparent after debonding when photographed at rotations of 0° mesiodistal and up to 20° buccal. Precaution must be taken into account assessing demineralizations of patients undergoing treatment with fixed appliances when using a QLF-D camera.

Validity assessment of quantitative light-induced fluorescence-digital (QLF-D) for the dental plaque scoring system: a cross-sectional study.

BACKGROUND: The aim of this study was to analyze the correlation between the dental plaque indices measured using quantitative light-induced fluorescence-digital (QLF-D) and conventional clinical indices that assess gingival status. METHODS: From among the patients who visited Ewha Womans University Mokdong Hospital, 33 adults in their 20s who had relatively even teeth were selected for full-mouth QLF-D imaging. The images were used to analyze the QLF-D score and the QLF-D ΔR score. As clinical indices, the gingival index (GI), bleeding on probing (BOP), probing pocket depth (PPD), and patient hygiene performance (PHP) index were measured. The correlations between the QLF-D score and QLF-D ΔR score and each clinical index were analyzed. Analyses were performed comparing the indices of maxillary and mandibular teeth, the teeth on right and left sides of the mouth, anterior and posterior teeth, and buccal and lingual surfaces of each tooth. Pearson's correlation analysis was conducted (p < 0.05). RESULTS: The mean full-mouth QLF-D score was highly correlated with the GI, BOP, PPD, PHP index (p < 0.01). The mean full-mouth QLF-D score showed the highest correlation with GI (r = 0.749) and the lowest correlation with PPD (r = 0.683). The correlations between the QLF-D score were higher in the mandible than in the maxilla and in the anterior teeth than in the posterior teeth, while no significant differences were seen between the buccal and lingual surfaces of tooth. CONCLUSIONS: This study concluded that the correlations between the plaque indices measured for each tooth surface area using QLF-D and the clinical indices assessed were significantly high, and it allowed objective determination of the gingival status. Therefore, the plaque index measured using QLF-D may be used as an alternative to supplement the shortcomings of conventional clinical indices for educating patients about plaque control and continued patient oral care.

Validation of Quantitative Light-Induced Fluorescence for Quantifying Calculus on Dogs' Teeth.

Periodontal disease is a common disease of dogs and is initiated by the buildup of plaque on the tooth surface. As plaque matures, it becomes mineralized to form calculus, which although not directly involved in the etiology of periodontal disease, provides an irregular surface to which plaque can adhere. Evaluation of the quantity of plaque and calculus on dogs' teeth is therefore essential to enable the efficacy of products, designed to prevent or retard plaque and calculus accumulation, to be evaluated. The objective of this study was to determine whether quantitative light-induced fluorescence (QLFTM) is a suitable tool to quantify the amount of calculus on the buccal surface of dogs' teeth following the removal of disclosed plaque by tooth brushing. The amount of calculus on the teeth of 26 miniature schnauzers was measured, using QLF and a calculus index method (Warrick-Gorrel), during a 28-day phase crossover study comparing feeding a daily dental chew versus providing no daily chew. Quantification of calculus using the Warrick-Gorrel method showed a 43.8% reduction in calculus buildup, with 95% confidence interval of 27.3 to 60.3 ( P < .001). With QLF, the percentage reduction in calculus accumulation was 65.8% (58.1-73.4, P < .001). A retrospective sample size analysis showed that fewer dogs were required for QLF analysis compared to the Warrick-Gorrel method. This study demonstrated that QLF is a sensitive and precise method for quantification of calculus on dogs' teeth. It removes the subjective element of human examiners and has greater accuracy and reduced variability through the continuous nature of the data.

Analysis of Orange/Red Fluorescence for Bacterial Activity in Initial Carious Lesions May Provide Accurate Lesion Activity Assessment for Caries Progression.

ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION: Orange/Red Fluorescence of Active Caries by Retrospective Quantitative Light-Induced Fluorescence Image Analysis. Gomez GF, Eckert GJ, Zandoná AF.Caries Res 2016; 50(3):295-302. SOURCE OF FUNDING: The study was partially supported by a grant from NIH/NIDCR (R01DE017890) TYPE OF STUDY/DESIGN: Retrospective case-control design using the data collected in a longitudinal study.