Quantitative light-induced fluorescence images and digital photographs - Reproducibility of manually marked demineralisations

Aesthetic caries infiltration - Long-term masking efficacy after 6 years

OBJECTIVES

This study aimed to evaluate the masking efficacy of caries infiltration technique of initial caries lesions (ICL) six years after debonding and single treatment.

METHODS

In 10 adolescents, 74 ICL (ICDAS 2) in 74 teeth were treated by resin infiltration (Icon, DMG) at a mean (SD) of 1.2 (1.2) months after bracket removal. The etching procedure was performed up to 3 times. Standardized digital images were taken before treatment (T₀), seven days (T₇) and 6 years (T₂₁₉₀) after treatment. Outcomes included the evaluation of the color differences between carious and healthy enamel at T₀, T₇ and T₂₁₉₀ by quantitative colorimetric analysis (ΔE), ICDAS scores, quantitative light-induced fluorescence (QLF; ΔF,ΔQ,WS Area) and qualitative visual evaluation (5-point Likert-scale [deteriorated (1), unchanged (2), improved, but not satisfying (3), improved and no further treatment required (4), completely masked (5)).

RESULTS

The median color difference ΔΕ₀ (25^th/75^th percentiles) at T₀ was 10.3 (8.56/13.0). At T₇ a significant decrease was observed (ΔΕ₇=3.7 (2.0/5.8); p<0.001; Friedmann-test; ICDAS p<0.001; Chi-square test). No significant changes based on ΔΕ (p=0.972; Friedmann-test) and ICDAS grading (p=0.511, chi-square test) were observed between T₇ and T₂₁₉₀ (ΔΕ₂₁₉₀=2.9 (1.8/4.2)). Furthermore, at T₂₁₉₀ four experienced dentists classified 50% and 37% of the lesions as "improved and no further treatment required" and "completely masked", respectively (Fleiss kappa: T₂₁₉₀: 0.782 (substantial agreement)).

CONCLUSION

Aesthetic caries infiltration can effectively mask post-orthodontic initial caries lesions for at least 6 years. These results for most of the teeth could not only be observed by quantitative but also by qualitative analysis.

CLINICAL SIGNIFICANCE

Resin infiltration efficaciously masks post-orthodontic initial carious lesions. The optical improvement can be observed directly after treatment and remains stable for at six years.

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).

Validation of clinical photography and a laser fluorescence device for assessment of enamel demineralization during multi-bracketed fixed orthodontic treatment

AIM

To compare the validity of DIAGNOdent pen™ 2190 and clinical photographs in the diagnosis (presence or absence) and assessment of white spot lesions (WSLs) during multi-bracketed fixed orthodontic treatment.

METHODS

A total of 1607 readings from 99 patients were obtained using DIAGNOdent pen™ 2190, clinical photographs, and visual assessment criteria to assess WSLs at 6 -, 12- and 18 months after bonding of brackets. Receiver operating characteristic curves were constructed, and areas under the curve (AUC) were calculated to assess the presence or absence of WSLs and distinguish the severity of WSLs as slight or severe. Sensitivities, specificities, and AUC were calculated for outcomes at an alpha of 0.05 and 95% confidence intervals (CIs).

RESULTS

The values of sensitivity and specificity of DIAGNOdent pen™ 2190 were found to be 0.78 and 0.83, respectively, to distinguish presence/absence of WSLs with good accuracy (AUC= 0.855; 95% CI: 0.820-0.889) and for digital photographs, accuracy was excellent (AUC= 0.973, 95% CI: 0.956-0.991) with sensitivity and specificity of 0.96 and 0.99, respectively. However, the accuracy of DIAGNOdent pen™ 2190 was poor (AUC= 0.543, 95% CI: 0.418-0.668) in delineating slight and severe WSLs with a sensitivity of 0.31 and specificity of 0.83; while the values of sensitivity and specificity for distinguishing slight or severe lesions for clinical photographs were 0.96 and 0.99, respectively with excellent accuracy (AUC=0.978, 95% CI: 0.936-1.000).

CONCLUSIONS

Clinical photographs had better validity than DIAGNOdent pen™ 2190 in diagnosis and assessment of severity of demineralized lesions during multi-bracketed fixed orthodontic treatment.

Demineralization detection in orthodontics using an ophthalmic optical coherence tomography device equipped with a multicolor fluorescence module

OBJECTIVES

Demineralizations such as white spot lesions are among the most prevalent side effects during orthodontic treatment. Fluorescence devices, including quantitative light-induced fluorescence (QLF), exploiting the intrinsic fluorescence of enamel and teeth and most recently optical coherence tomography (OCT) were introduced for early demineralization detection. In addition to near-infrared OCT scanning, multicolor modules allow for imaging with different laser wavelengths and the detection of reflective- and fluorescent light. The aim of this study was to evaluate a modified multicolor ophthalmic OCT device for the detection of early carious lesions in vitro and in vivo.

MATERIALS AND METHODS

Twenty-seven extracted lesion free human teeth were randomly assigned to three different demineralization protocols. Carious lesion detection was performed using macrophotography, OCT, and reflectance/fluorescence imaging using green laser and blue laser light. In addition, teeth of 5 orthodontic patients were OCT scanned, and fluorescence imaging using blue laser light was performed to assess demineralization after orthodontic therapy.

RESULTS

Both in vitro and in vivo, OCT allowed for precise determination of lesion depth and enamel loss. Fluorescence imaging using blue laser light was most sensitive for the detection of early demineralization in vitro and in vivo. However, established and severe demineralizations were also reliably detected by macrophotography in vitro and in vivo.

CONCLUSION

Demineralization can be detected with high sensitivity using blue fluorescence imaging with multicolor OCT devices.

CLINICAL RELEVANCE

In the future, OCT fluorescence imaging might be considered for longitudinal monitoring of dental hard tissue during orthodontic treatment in clinical trials.

Spatial agreement of demineralized areas in quantitative light-induced fluorescence images and digital photographs

OBJECTIVES

Previous work has shown qualitatively that detection of demineralized tooth areas (white spot lesions, WSLs) is more reliable in digital photographs (DP) as in quantitative light-induced fluorescence (QLF) images. Based on non-rigid, multimodal image registration, we now quantitatively compare manual and automatic markings in both modalities.

METHODS

After braces removal, pairs of DP and QLF were acquired from 124 teeth of 31 patients. Three experienced raters marked the WSL on both DP and QLF images, each of which was presented twice in randomized order. For each tooth and each modality, a ground truth (GT) was established using the simultaneous truth and performance level estimation algorithm on the total of six manual markings per image. DP and QLF image pairs were spatially registered, by aligning the outline of the tooth area in DPs to that of the corresponding tooth area in QLF. Between all pairs of markings for all teeth, position and size were compared quantitatively by the Dice coefficient and the novel coefficient of inclusion.

RESULTS

Our hypotheses: (i) the clinical inspection supported by DP is more sensitive to WSL as that by QLF, disregarding whether the automatic analysis or the experts' manual assessment of QLF is applied, and (ii) detected lesions in QLF are included in those of DP, were confirmed and not confirmed, respectively.

CONCLUSION

DP and QLF are valuable methods to detect WSL in demineralized teeth. Combining both modalities can provide additional information on early lesion assessment.