Remineralization of post-orthodontic white spot lesions with a fluoride varnish and a self-assembling P 11 - 4 peptides: a prospective in-vivo-study.

OBJECTIVE: The objective was to evaluate the remineralization effects of fluoride varnish (Clinpro White varnish), self-assembling peptide (Curodont™ Repair) and their combined use on WSL after orthodontic treatment. MATERIALS AND METHODS: Thirty-two subjects, aged of 10-18 (mean age 13.91 ± 2.92) with 107 post-orthodontic WSL were included in the study. Subjects were divided into four groups as control, tricalcium phosphate (TCP) containing fluoride varnish (Clinpro White varnish) group, self-assembling P11-4 peptides (Curodont™ Repair) group and combined application of the two products. At the beginning, each subjects' caries risk profile was assessed by evaluating diet cariogenicity, plaque index, gingival bleeding index and stimulated salivary flow rate. Before the application of the remineralization agents, WSL baseline demineralization values were determined with QLF Inspektor™ Pro, laser fluorescence using DIAGNOdent and color values were measured by Vita EasyShade. Remineralization data were obtained by measuring ΔF, ΔQ, and lesion area with QLF. The aesthetic improvement after the remineralization process was evaluated with a spectrophotometer at six weeks, three and six months. RESULTS: No statistically significant differences were found between the groups in terms of criteria determining patients' caries risk profiles, DIAGNOdent data, and plaque index scores (p > 0.05). Intra-group evaluation following remineralization revealed statistically significant increases in ΔF and ΔQ with a decrease in lesion area for the fluoride varnish group at six months, for the peptide group at three months, and for the combined application group at three and six months (p < 0.05). In inter-group comparisons, ΔF and ΔQ values were found to be statistically significant only in the fluoride group at six months compared to the other groups (p < 0.05). While the L* value decreased significantly in all groups at six months, a statistically significant difference in ΔE* values was observed only in the control group between three and six months. CONCLUSION: Fluoride varnish with TCP showed highest remineralization at 6 months, and the remineralization was positively affected in the short term (three months) after the use of self-assembling P11-4 peptides and their combined application. CLINICAL RELEVANCE: Remineralization obtained after single application of agents tested in six months in-vivo showed parallel results. In an attempt to trigger subsurface remineralization, the combined use of fluoride with self-assembling peptides as biomimetic remineralization agent needs further evaluation.

The use of quantitative light-induced fluorescence in carious lesions research: A bibliometric review.

OBJECTIVE: This bibliometric analysis evaluated the top 100 most-cited articles on the application of quantitative light-induced fluorescence (QLF) technology in caries research. DATA: The following data were collected: title, authors, country, institution, citations count, title and year of article, study design, topic and keywords. Networks among authors and keywords were constructed by VOSviewer software. SOURCES: Scopus database on April 25, 2024. STUDY SELECTION: A global citation score of 4633 (average 46.33 citations) was calculated with publication years ranged from 1999 to 2020. Caries Research emerged as the top contributing journal. Pretty IA was the most prolific author (18 %). United Kingdom had the highest number of most-cited papers (32 %), followed by Netherlands and USA (20 % each). Laboratory studies constituted the predominant study design (45 %), followed by randomized clinical trials (20 %) and non-systematic reviews (11 %). The keywords "dental caries" and "fluorescence" had 81 and 79 occurrences, respectively. The main topic was QLF use for caries detection (45 %). CONCLUSIONS: This paper provides an update summary of the scientific impact of QLF technology application in caries research. QLF has gained increasing attention worldwide, accompanied by a consistent rise in scientific investigations exploring its application in caries research. CLINICAL SIGNIFICANCE: The findings offer valuable insights into the most influential articles in QLF technology for caries assessment, serving as a critical resource for researchers, clinicians, and students. Understanding the trends in this field can aid in informed decision-making and the advancement of evidence-based practices in caries management and prevention.

A Comparison of the Fluoride 'Paint- On' vs Tray Application Techniques for Enamel Remineralisation.

BACKGROUND: Fluoride gel treatment is not recommended for children < 6 years old due to its potential toxicity. Hence the aim of this study was to compare the effect of 1.23% acidulated-phosphate fluoride (APF) gel paint-on and the conventional tray application techniques on artificial, deciduous enamel carious lesions embedded on wearable appliances. METHODS: In a randomised crossover study, the volunteer children (n = 29) wore mandibular removable appliances containing embedded tooth specimens with artificial carious lesions. The volunteers had 3 different treatment protocols: (I) 0.4 mL non-fluoride (control) gel, (II) 0.4 mL paint-on 1.23% APF gel or (III) 5 mL 1.23% APF gel, 4 minutes tray application. After 1 hour, the appliances were removed and the specimens underwent an in vitro, 14 days of pH-cycling. The mean percentage reduction in fluorescence (ΔF, %) at baseline (ΔF0) and after the pH-cycling (ΔF1) were determined using quantitative light-induced fluorescence-digital analysis. The mean ΔΔF (ΔF1-ΔF0) was calculated to compare the differences between groups. RESULTS: The mean ΔΔF of groups I to III were -1.42 ± 1.49, 1.06 ± 2.11, and 1.12 ± 3.57 and -1.25 ± 1.44, 1.13 ± 1.84 and 1.44 ± 3.62 for the smooth surface and proximal surface lesions, respectively. The mean ΔΔF in the 2 treatment groups were significantly greater compared with the control group (P < .001). There was no significant difference in ΔΔF between the APF gel tray and paint-on groups either in the smooth surfaces, or the proximal surfaces (P = .629 and P = .613, respectively). CONCLUSION: Our study, for the first time, indicates that the paint-on application of APF gel or the tray application of APF had a similar enamel remineralisation effect. Clinically, this implies that, particularly in younger children, the paint-on application of fluoride is less cumbersome, and possibly more tolerable with a lesser likelihood of fluoride ingestion than the tray application technique. TRIAL REGISTRATION: Thai Clinical Trial Registry (https://www.thaiclinicaltrials.org/show/TCTR20190724001).

Quantitative light-induced fluorescence enables effective detection of orthodontic adhesive residues in diverse environments.

BACKGROUND: Adhesive remnants post-orthodontic treatment might have deleterious effects on oral health, including enamel demineralization, plaque accumulation, and elevated risk of caries development. The aim of this study was to identify and characterize adhesive residues in an ex vivo environment rich in salivary microbiota using quantitative light-induced fluorescence (QLF) technology. METHODS: Disc-shaped adhesive samples with thickness ranging from 800 to 100 µm were prepared using GC Ortho, GOTO, T Orthobond, and Transbond XT and subsequently evaluated utilizing a QLF system. Bovine teeth containing GC Ortho and GOTO adhesives and isolated human premolar teeth bonded with brackets were subjected to a 10-day incubation in an artificial saliva environment. Daily imaging was conducted using QLF during incubation. Data with ΔR > 30% and simple hygiene score (SHS) were obtained with a software for further analysis. RESULTS: Fluorescence intensity exhibited significant differences among the four orthodontic adhesives (p < 0.05). Results of incubation in artificial saliva revealed that red fluorescence surrounding the adhesive on the tooth surface was distinctly observable from day five onwards, with ΔR > 30% and SHS levels higher than those of the control group without adhesive (p < 0.05). Observation of fluorescence images of isolated human premolar teeth with bonded brackets indicated that red fluorescence was primarily present around the brackets. CONCLUSIONS: Application of QLF is efficacious in identifying and demarcating adhesive residues within an environment rich in salivary microbiota.

Comparison of three orthodontic bonding systems in white spot lesion development: a randomized clinical trial.

OBJECTIVES: To compare the development of white spot lesions (WSLs) during fixed orthodontic therapy among a conventional three-step bonding system, a self-etching primer bonding system, and a one-step adhesive bonding system. MATERIALS AND METHODS: Seventy-five patients were randomly allocated into three groups (group 1, conventional bonding system, n = 25; group 2, self-etch primer, n = 25; group 3, primer mixed with adhesive composite, n = 25). Quantitative light-induced fluorescence (QLF) was used to assess WSL parameters. Images were captured and then analyzed before treatment and at 2 months and 4 months after bond up. Lesion area (pixels), mean fluorescence loss (ΔF), and the number of newly developed WSLs were compared within and among the three groups. The significance level was P ≤ .05. RESULTS: The mean increase in lesion area was 31.3 ± 2.8 pixels, 38.4 ± 4.3 pixels, and 119.5 ± 5.3 pixels for groups 1, 2, and 3, respectively (P ≤ .001). For ΔF, the loss was 3.3% ± 0.3%, 4.4% ± 0.2%, and 6.6% ± 0.2% for groups 1, 2, and 3, respectively. These changes were significantly different (P ≤ .01 to P ≤ .001). The incidence of newly developed lesions was 9.5 WSLs in group 1, 10 WSLs in group 2, and 15.9 WSLs in group 3. CONCLUSIONS: The lack of primer contributed to the development of a larger number of and more severe WSLs.

Optical detection of oral biofilm in hospitalized geriatric patients using quantitative light-induced fluorescence technology.

Detection and removal of pathological oral biofilm are essential in hospitalized geriatric patients as the biofilm can lead to lung infection. However, as elderly patients often have cognitive and physical impairments, general oral examination is complicated and detection of pathological biofilms is challenging. Quantitative light-induced fluorescence (QLF) technology, which is currently actively used to detect bacterial structures in the oral cavity, is used to detect dental biofilm and to identify various oral bacterial infections. We confirmed the applicability of QLF technology to oral hygiene assessment and evaluation of hospitalized geriatric patients using the QLF technology to detect and remove the pathological oral biofilm in a hospitalized geriatric patient. The oral biofilm attached to the oral mucosa was difficult to observe with the naked eye. However, it was detected with red fluorescence on QLF images, which helped us observe the to detect pathological oral biofilm and evaluate the effectiveness of oral hygiene care (OHC). After OHC, the strong red fluorescence expressed in the oral mucosa was no longer observed. This change in the clinical aspect of red fluorescence suggests that QLF can be used to detect pathological oral biofilm accumulated on the oral mucous membrane and evaluate the effectiveness of OHC in hospitalized patients with extremely poor oral hygiene.

How do carious root lesions develop after the end of professional preventive measures?-Preliminary findings of a randomized clinical trial.

Aim of this randomized clinical trial was to assess the development of root caries lesions with and without (adjuvant) professional prevention treatment over 24 months. 20 participants with two or three non-cavitated root carious lesions were included (n = 52), whereby lesions were randomly assigned to one out of three groups depending on varnish application (CF: Cervitec F [n = 20], P: placebo [n = 20], DP: Duraphate [n = 12]). All lesions were assessed by quantitative light-induced fluorescence (QLF; QRayCam); following outcome parameters were analyzed: fluorescence loss (ΔF %), lesion volume (ΔQ %µm2) and bacterial activity (ΔR %). Professional tooth cleaning and adjuvant varnish application were performed at baseline, after 3, 6, and 9 months. A follow-up examination was performed 1 year after preventive care with varnish application 24 months after baseline. ∆F showed a significant time effect in CF (p = 0.03), which was not confirmed in post hoc analysis (p > 0.05). For P and DP, no time effect was detected (p > 0.05). ∆Q was significantly higher 12 months after baseline in CF (p = 0.02). In P, a significant time effect occurred (p = 0.01), without significant results in post hoc testing. ∆R showed higher values at baseline vs. 12 months in CF (p = 0.03) and 24 months compared to 12 months in DP (p = 0.02). Professional preventive treatment inhibited the progression of root caries lesions beyond their termination for 12 months, irrespective of an adjunctive varnish application. Preventive measures have a long-term effect on root carious lesions, even 1 year after their termination.

A Semi-Automated Method for Measuring Biofilm Accumulation on the Teeth Using Quantitative Light-Induced Fluorescence in Dogs and Cats.

Oral health conditions (eg, plaque, calculus, gingivitis) cause morbidity and pain in companion animals. Thus, developing technologies that can ameliorate the accumulation of oral biofilm, a critical factor in the progression of these conditions, is vital. Quantitative light-induced fluorescence (QLF) is a method to quantify oral substrate accumulation, and therefore, it can assess biofilm attenuation of different products. New software has recently been developed that automates aspects of the procedure. However, few QLF studies in companion animals have been performed. QLF was used to collect digital images of oral substrate accumulation on the teeth of dogs and cats to demonstrate the ability of QLF to discriminate between foods known to differentially inhibit oral substrate accumulation. Images were taken as a function of time and diet. Software developed by the Cytometry Laboratory, Purdue University quantified biofilm coverage. Intra- and intergrader reproducibility was also assessed, as was a comparison of the results of the QLF software with those of an experienced grader using undisclosed coverage-only metrics similar to those used for the Logan and Boyce index. Quantification of oral substrate accumulation using QLF-derived images demonstrated the ability to distinguish between dental diets known to differentially inhibit oral biofilm accumulation. Little variance in intra- and intergrader reproducibility was observed, and the comparison between the experienced Logan and Boyce grader and the QLF software yielded a concordance correlation coefficient of 0.89 (95% CI = 0.84, 0.92). These results show that QLF is a useful tool that allows the semi-automated quantification of the accumulation of oral biofilm in companion animals.

Evaluation of quantitative light-induced fluorescence to assess lesion depth in cavitated and non-cavitated root caries lesions - An in vitro study.

BACKGROUND: This in vitro study aimed to assess carious lesions on root surfaces using quantitative light-induced fluorescence (QLF) and to compare the readings with axial lesion depth on µCT. METHODS: The root surfaces of 107 extracted human teeth were included after visual-tactile inspection. For further analysis, the following parameters were assessed: clinical findings (non-cavitated: leathery or hard, cavitated), QLF- (QLF-D Biluminator 2+), and µCT-images (Bruker Skyscan 1172). The shape of the undamaged tooth surface of the cavitated lesions was virtually re-constructed during µCT analysis. Clinical surface texture,% fluorescence loss, and lesion depth (µCT) were determined. STATISTICAL ANALYSIS: chi²-test, Spearman-Rho test, regression analysis. RESULTS: ∆F was significantly lower in non-cavitated leathery (-50.37 ± 15.10) and cavitated (-61.23 ± 9.92) compared to non-cavitated surfaces with a hard texture (-17.04 ± 16.10, p < 0.01). For non-cavitated surfaces, a negative correlation was observed between ∆F and lesion depth in µCT images regardless of texture (-0.748, p < 0.01). Regression analysis revealed that ∆F predicted lesion depth in µCT for non-cavitated surfaces (ß: 0.703, CI95: 0.67--0.43, p < 0.01). CONCLUSION: The percentage of fluorescence loss (∆F) in QLF predicted lesion depth of non-cavitated demineralized root surfaces. Therefore, QLF can be recommended for estimating the lesion depth of carious root lesions and seems to expand the possibilities of follow-up and lesion monitoring, especially for non-cavitated surfaces.

A novel model to predict tooth bleaching efficacy using autofluorescence of the tooth.

OBJECTIVES: We aimed to confirm whether autofluorescence emitted from teeth can predict tooth bleaching efficacy and establish a novel model combining natural color parameters and tooth autofluorescence data to improve the predictability of tooth bleaching. METHODS: A total of 61 tooth specimens were prepared from extracted human molars/premolars and immersed in 35% hydrogen peroxide for 1 h for tooth bleaching. The changes in laser-induced fluorescence (∆LIF) were assessed using Raman spectrometry. Tooth color and autofluorescence data were obtained using quantitative light-induced fluorescence (QLF) technology. Pearson correlation analyses were used to confirm the relationship between ∆LIF and autofluorescence. Intraclass correlation coefficients (ICC) were calculated to compare the conventional and new prediction models. Decision tree analysis was performed to evaluate clinical applicability. RESULTS: The yellowness-to-blueness value from fluorescence imaging showed a moderate correlation with ∆LIF (r= -0.409, p = 0.001). The degree of agreement between the actual efficacy and that predicted by our novel model was high (ICC=0.933, p = 0.002). Decision tree analysis suggested that tooth autofluorescence could be a key factor in prediction of tooth bleaching outcomes. CONCLUSIONS: Our findings showed that autofluorescence detected from QLF images may be used to predict tooth bleaching efficacy. Our proposed model appeared to improve the predictability of tooth bleaching.

The diagnostic efficacy of quantitative light-induced fluorescence in detection of dental caries of primary teeth.

OBJECTIVES: To evaluate a quantitative light-induced fluorescence (QLF) caries detection method using a portable device under clinical conditions and present a QLF scoring index (QS-index) for primary teeth. METHODS: A total of 878 tooth surfaces (proximal and occlusal) of 44 children were studied. After visual inspection and radiographic examination, images of dental caries captured with the QLF device were classified according to caries progression stages and analyzed with a specialized software. Cut-off values, sensitivity, specificity, and area under the receiver operating characteristic curve (AUROC) were calculated for the QLF parameters: fluorescence loss (ΔF) and bacterial activity (ΔR). The reliability of logistic regression model to combine ΔF and ΔR was evaluated by the AUROC. RESULTS: QLF parameters showed a good sensitivity (0.72-0.91), specificity (0.74-0.96), and AUROC (0.861-0.940). The AUROC of logistic regression model (0.90-0.957) was higher than ΔF or ΔR average alone in all types of carious lesions. Every level of the QS-index was properly defined to represent the progression of dental caries with corresponding statistical significance. CONCLUSIONS: The reliability of QLF for dental caries detection in primary teeth was similar to or slightly higher than that of the traditional diagnostic methods of visual inspection or radiographic examination in clinical conditions. CLINICAL SIGNIFICANCE: The results of QLF were reliable in detecting all types of dental caries in primary teeth. The QLF method can provide visual images as well as quantitatively analyze the carious lesion.

Optical detection of the potential for tooth discoloration from children's beverages by quantitative light-induced fluorescence technology.

BACKGROUND: Some beverages are known to cause extrinsic staining on the tooth. This study investigated the degree of pigmentation caused by children's acidic beverages, and to confirm the possibility of the quantitative light-induced fluorescence (QLF) technology in assessing staining of the tooth. METHODS: Bovine tooth specimens were subjected to an 8-day pH-cycling model, using six children's beverages (experimental groups) and a cola (control group), and a remineralizing solution. Before and after the pH-cycling, white-light and fluorescence images of the enamel surface were photographed with a QLF to evaluate color change (ΔEafter) and fluorescence loss (ΔFafter), respectively. Paired t-test was used to compare the tooth colors obtained before and after the pH-cycling. Spearman correlation analysis was performed to examine the correlation between the ΔEafter and ΔFafter values. RESULTS: Median ΔEafter values of all the beverages ranged from 1.33 to 20.42, showing the greatest value in Koal-Koal Koala™ (KKK, p < 0.001). The ΔEafter was correlated with ΔFafter value negatively (ρ=-0.611, p < 0.001). The median ΔFafter varied by beverages (-38.86-0.00) and KKK caused the greatest value. CONCLUSIONS: The cola and 6 children's beverages showed the possibility for discoloration on the tooth. The QLF technology may enable monitoring the discoloration induced on the tooth surface by acidic beverage.

Amelogenin Peptide-Chitosan Hydrogel for Biomimetic Enamel Regrowth.

We designed synthetic peptides that have demonstrated an effective remineralization potential to restore incipient enamel decay. In order to develop a clinically viable approach we incorporated the amelogenin-derived peptides P26 and P32 into chitosan hydrogel and examined their efficacy in the remineralization of enamel. Peptides in chitosan exhibited increased stability in vitro as compared to peptides in solution at room temperature and at 37°C. Tooth models for enamel erosion (sections) and white spot lesions (blocks) were subject to periods of demineralization. Treatment groups were subjected to remineralization in artificial saliva in the presence of P26 and P32 in solution and in chitosan hydrogel (P26-CS and P32-CS). Quantitative light-induced fluorescence (QLF) was employed to analyze mineral density following demineralization and remineralization across all the treatment groups. Scanning electron microscopy and nanoindentation were used to characterize the surface structure and mechanical strength of regrown enamel. Control enamel sections treated in artificial saliva demonstrated randomly distributed, tiny, needle-shaped crystals with a low packing density and porosities displaying mineralization defects. In samples treated with P26-CS or P32-CS a denser coating of organized hydroxyapatite (HAP) crystals was formed covering the entire surfaces of demineralized enamel window. The hardness and modulus of enamel surfaces were increased after treatment with P26-CS and P32-CS with no significant difference in the mechanical properties between the two peptide hydrogels. Analysis of mineral density by QLF showed that in enamel sections P26 peptide alone or P26-CS significantly enhanced the remineralization. In enamel blocks P26 in solution had a better efficacy than P26-CS.

Quantitative light-induced fluorescence as a potential tool for detection of enamel chemical composition.

BACKGROUND: Little is known about how the chemical composition of enamel affects the optical properties of teeth, but advances in technology allow this to be studied using white-light and fluorescent images. This study aimed to identify the variation in enamel chemical composition that may affect tooth optical properties, such as tooth color and autofluorescence. METHODS: Sixty-one specimens of extracted human molars were prepared. Raman spectrometry was used to assess chemical composition of enamel, and tooth color, and autofluorescence from enamel were evaluated by quantitative light-induced fluorescence (QLF) images. Pearson correlation and multiple linear regression analyses were used. RESULTS: Enamel fluorescence was related to enamel composition rather than tooth color. The b* value from the fluorescence image had a moderate correlation with crystallinity (full-width at half-maximum: r = -0.433, p < 0.001) and laser-induced fluorescence intensity (r = 0.450, p < 0.001) from Raman spectroscopy. In multiple linear regression analysis, the chemical composition of the tooth had a significant effect on the b* value from the fluorescent image (R2 = 0.433, p < 0.001). In contrast, tooth color values (L*, a*, and b*) were not correlated with chemical composition. CONCLUSIONS: The present study revealed that enamel autofluorescence in QLF was related to chemical composition of the enamel, particularly the inorganic‒organic interface. While enamel chemical composition can be detected only in a laboratory environment, enamel fluorescence by QLF may enable estimation in a dental clinic, which has implications for the field of tooth bleaching or esthetic restorative materials.

Red fluorescence of plaque in the dentition-a comparison of Quantitative Light-induced Fluorescence-Digital (QLF-D) images and conventional images of disclosed plaque.

BACKGROUND: Quantitative Light-induced Fluorescence-Digital (QLF-D) detects red fluorescence of plaque, but is almost solely used on labial anterior tooth surfaces. As distribution and formation of plaque varies distinctly within the dentition, our aim was to investigate, how red fluorescing plaque is related to disclosed plaque depending on tooth type and surface. This was done with habitual plaque and after de-novo plaque formation. METHODS: Thirty subjects were enrolled. QLF-Dimages of undisclosed plaque and conventional images of disclosed plaque were planimetrically analysed. Values were expressed as percentage of red fluorescing plaque (P%QLF-D) and of disclosed plaque (P%D) of the total tooth surface. Images were taken at baseline, after de-novo plaque formation (48 (T2) and 72 (T3) h without oral hygiene after professional tooth cleaning), and after 4-6 weeks of habitual oral hygiene (T4). RESULTS: At the tooth level, P%QLF-D was significantly lower than P%D on vestibular surfaces but reached similar levels on oral surfaces. De-novo plaque formation caused a significant increase in P%D on vestibular surfaces; this was not reflected by QLF-D. At the subject level, on vestibular surfaces and at baseline, some subjects exhibited minor but others gross differences between P%QLF-D and P%D. This was not the case at T3, but the same pattern appeared again at T4. On oral surfaces, the order of differences was more evenly scattered with no clear impact of the observation time point. CONCLUSION: Red fluorescence of dental plaque relates very differently to disclosed plaque depending on sites and maturation stages and has a significant inter-individual component.

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.

Noninvasive detection of microleakage in all-ceramic crowns using quantitative light-induced fluorescence technology.

The early noninvasive detection of crown microleakage is very important for tooth maintenance and preservation. A crown margin in a subgingival position combined with the obscuring effect of a ceramic crown make it difficult to diagnose microleakage using traditional methods such as visual-tactile examinations and radiography. The aim of this study was to determine the effectiveness of quantitative light-induced fluorescence (QLF) technology for diagnosing microleakage in an all-ceramic crown noninvasively. In this study the red fluorescence glow was detected through a crown wall using the Qraycam QLF device (AIOBIO, Seoul, Republic of Korea). No abnormalities were detected by a visual examination, whereas the Qraycam device revealed both strong red fluorescence and fluorescence loss in suspicious lesions, which were confirmed after crown removal. It was possible to determine that the carious lesions inside the crown were related to bacteria-induced microleakage. After performing caries removal and crown reattachment, the red fluorescence glow was no longer detected. QLF examinations made it easy to identify the presence of microleakage in an all-ceramic crown noninvasively based on red fluorescence. These findings indicate that QLF technology can be effectively applied to provide objective evidence for detecting microleakage and diagnosing carious lesions inside an all-ceramic crown noninvasively.

Assessment of non-cavitated root caries lesions by quantitative light-induced fluorescence-An in vivo feasibility study.

OBJECTIVES: To evaluate the reproducibility of quantitative light-induced fluorescence (QLF) for the detection and assessment of demineralization states of non-cavitated root surfaces and to determine the correlation between visual inspection and QLF-analysis. METHODS: 46 exposed non-cavitated root surfaces of 12 participants were classified in three scores: sound (0), lesion ≤ 5 mm (1a), lesion > 5 mm in diameter (1b). Three examiners imaged every root surface three times using QLF (QRayCam) and measured fluorescence loss (ΔF) and lesion volume (ΔQ). The QLF-images were analyzed by three examiners. The intra- and interexaminer reproducibilities were calculated (intraclass correlation coefficient, ICC). The correlation between the scores of root caries and QLF-analysis was determined (rank correlation coefficient, Spearman-Rho ρ). RESULTS: Intra- and interexaminer reproducibility (ICC) was 0.98 and 0.95 for ΔF, 0.94 and 0.91 for ΔQ, respectively. A significant correlation was observed between the scores and ΔF (ρ = -0.53, p < 0.01). CONCLUSION: QLF as a reproducible diagnostic tool enables non-invasive detection and differentiation of non-cavitated root caries lesions on root surfaces in vivo. It can be recommended in addition to the clinical evaluation for prospective follow-up examinations of demineralization states of exposed root surfaces.

Assessment of the effects of a fluoride dentifrice and GC Tooth Mousse on early caries lesions in primary anterior teeth using quantitative light-induced fluorescence: a randomised clinical trial.

PURPOSE: To compare the effects of a fluoride dentifrice alone, versus a topical CPP-ACP crème used as a dentifrice, versus the combination of both agents (fluoride dentifrice followed by CPP-ACP crème) on early caries lesions (ECL) in primary anterior teeth of children over a 6-month period. METHODS: In this single blinded randomised clinical trial, children (n = 114, aged 4-5 years) with high caries risk and who had at least one ECL (ICDAS 2) on their primary anterior teeth were allocated to three groups. Subjects used different agents twice daily: fluoride dentifrice (500 ppm F, n = 42), CPP-ACP crème (10% w/v, n = 35), and the fluoride dentifrice followed by CPP-ACP crème (n = 37). Changes in lesions were tracked using QLF, comparing the baseline situation to 3 and 6 months of treatment. RESULTS: QLF changes consistent with mineral gain (∆F/fluorescence, lesion area) occurred in all three groups (baseline versus 3 months or 6 months, p ≤ 0.05 for all three groups). Differences between treatment groups were not statistically significant (p > 0.05). CONCLUSION: The topical CPP-ACP crème used alone gave effects similar to the fluoride dentifrice; however, the combination of the two did not give additive benefits over either agent used in isolation.

Diagnosis and management of cracked tooth by quantitative light-induced fluorescence technology.

INTRODUCTION: The aim of this case report was to describe the process of diagnosis and treatment of a cracked tooth using quantitative light-induced fluorescence (QLF). CASE REPORT: A 43-year-old male presented at our dental clinic with a complaint of cold pain in #17 tooth. A routine oral examination with radiography was performed for evaluation of the oral condition and treatment planning. Additionally, QLF image capture was performed using Qraycam and Qraypen (AIOBIO, Seoul, Republic of Korea), to collect white-light and fluorescence images. The #17 tooth was observed to have a crack line, showing red fluorescence, from the distal to mesial aspect on the occlusal surface. Even though there was no visible root fracture in the radiographic image, bone loss was observed. Therefore, we performed periodontal treatment. One month later, a root canal treatment was performed because the patient still complained of pain in the #17 tooth. During this treatment, one fluorescent image and one white light image set was captured with the Qraypen. A crack line showing red fluorescence was observed, while the line was not visible to the naked eye. After treatment, the patient has had no complaint related to this tooth for 3 years until today. CONCLUSIONS: Clinically, use of QLF confirmed the presence of a crack before and during a root canal treatment. Therefore, it is postulated that the QLF technology could objectively facilitate the diagnosis and treatment of a cracked tooth.