Clinical Study on the Effect of Professional Cleaning of Occlusal Tooth Surfaces on Laser Fluorescence Measurements

Effects of pastes containing ion-releasing particles on dentin remineralization

We investigated the effects of the weekly application of pastes containing a surface reaction-type pre-reacted glass-ionomer (S-PRG) filler on dentin remineralization. Human dentin blocks were demineralized and polished using pastes containing S-PRG filler (0, 5, and 30%), and then immersed in remineralizing solution for 1 month. Nanoindentation testing was carried out during the immersion period, and the dentin surfaces were examined using scanning electron microscopy. A nano-hydroxyapatite-containing paste was used for comparison. Immersion in demineralization solution had a marked negative effect on the mechanical properties in all specimens. The mechanical properties of specimens polished with S-PRG filler-containing pastes recovered significantly after immersion in remineralization solution for 1 month compared with the other specimens. After remineralization, the open dentinal tubules were filled with a remineralization layer in specimens polished with S-PRG filler-containing and nano-hydroxyapatite-containing pastes. S-PRG filler-containing pastes can aid dentin remineralization.

The effects of single application of pastes containing ion-releasing particles on enamel demineralization

We investigated single application of pastes containing a surface reaction-type pre-reacted glass-ionomer (S-PRG) filler on enamel demineralization. Human enamel blocks were polished using pastes containing S-PRG filler (0, 5, and 30%) and immersed in demineralizing solution for 5 days with daily change of solutions. The pH measurement and nanoindentation testing was carried out during the immersion period, and the enamel surfaces were examined using scanning electron microscopy and atomic force microscopy. A non-fluoride paste and a hydroxyapatite-containing paste were used for comparison. The specimens polished with the S-PRG filler-containing paste exhibited acid-neutralizing properties, which became stronger with an increasing S-PRG filler content. Following immersion in the demineralizing solution, specimens polished with the S-PRG filler-containing paste exhibited significantly greater hardness and elastic modulus values than those polished with the other pastes and exhibited a smoother surface than did the other specimens. Pastes containing S-PRG filler inhibits the demineralization of enamel.

Laser fluorescence in monitoring the influence of targeted tooth brushing on remineralization of initial caries lesions on newly erupted molar teeth - RCT

OBJECTIVE

This study aimed to monitor mineralization changes in initial caries lesions on newly erupted second molars using laser fluorescence (LF) scanning after a 1-month targeted tooth brushing intervention.

METHODS

Altogether, 124 13- to 14-year-old school children were invited to participate. Of those who fulfilled the clinical criteria (at least one initial lesion with LF value >10 in second molars), 51 gave their written consent to participate. Laser fluorescence values were registered at baseline and after 1-month follow-up period. All participants were individually taught targeted tooth brushing of their second molars and randomly provided tooth paste with 0 or 1500 ppm fluoride. Brushing frequency was investigated at baseline and after the follow-up. Change in LF values was compared considering the tooth, content of fluoride in the paste and brushing frequency.

RESULTS

In lesions with LF values ≤30 at baseline, change in LF values demonstrated improvement. Improvement was detected especially in upper molars. In lesions with LF values >30 at baseline, improvement was least detected. Brushing frequency increased slightly during the intervention.

CONCLUSIONS

Laser fluorescence is a simple method and useful in monitoring remineralization of incipient lesions even in weeks. Targeted tooth brushing seems to induce remineralization even in weeks. Laser fluorescence could be a valuable motivating tool in promoting patients' self-care.

The performance of conventional and fluorescence-based methods for occlusal caries detection: an in vivo study with histologic validation

BACKGROUND

The authors conducted an in vivo study to determine clinical cutoffs for a laser fluorescence (LF) device, an LF pen and a fluorescence camera (FC), as well as to evaluate the clinical performance of these methods and conventional methods in detecting occlusal caries in permanent teeth by using the histologic gold standard for total validation of the sample.

METHODS

One trained examiner assessed 105 occlusal surfaces by using the LF device, LF pen, FC, International Caries Detection and Assessment System (ICDAS) criteria and bitewing (BW) radiographic methods. After tooth extraction, the authors assessed the teeth histologically. They determined the optimal clinical cutoffs by means of receiver operating characteristic curve analysis.

RESULTS

The specificities and sensitivities for enamel and dentin caries detection versus only dentin caries detection thresholds were 0.60 and 0.93 and 0.77 and 0.52 (ICDAS), 1.00 and 0.29 and 0.97 and 0.44 (BW radiography), 1.00 and 0.85 and 0.77 and 0.81 (LF device), 0.80 and 0.89 and 0.71 and 0.85 (LF pen) and 0.80 and 0.74 and 0.49 and 0.85 (FC), respectively. The accuracy values were higher for ICDAS, the LF device and the LF pen than they were for BW radiography and the FC.

CONCLUSIONS

The clinical cutoffs for sound teeth, enamel carious lesions and dentin carious lesions were, respectively, 0 through 4, 5 through 27 and 28 through 99 (LF device); 0 through 4, 5 through 32 and 33 through 99 (LF pen); and 0 through 1.2, 1.3 and 1.4 through 5.0 (FC). The ICDAS, the LF device and the LF pen demonstrated good performance in helping detect occlusal caries in vivo. The ICDAS did not seem to perform as well at the D(3) threshold (histologic scores 3 and 4) as at the D(1) threshold (histologic scores 1-4). BW radiography and the FC had the lowest performances in helping detect lesions at the D(1) and D(3) thresholds, respectively.

CLINICAL IMPLICATIONS

Occlusal caries detection should be based primarily on visual inspection. Fluorescence-based methods may be used to provide a second opinion in clinical practice.

Effects of different fissure sealant applications on laser fluorescence measurements

OBJECTIVE

The aim of this in vitro study was to evaluate the effects of using only phosphoric acid or a self-etch bonding agent under clear and opaque fissure sealants on laser fluorescence (LF) readings and the reproducibility of the laser device.

METHODS

Eighty extracted permanent molars, ranged from sound to carious, were randomly divided into four groups: phosphoric acid + opaque sealant (group I), Clearfil S3 Bond (Kuraray, Kurashiki, Japan) + opaque sealant (group II), phosphoric acid + clear sealant (group III), and Clearfil S3 Bond + clear sealant (group IV). The teeth were measured using an LFpen device, before and after sealing. Data were analysed using the Spearman's correlation, Wilcoxon signed rank, and Mann-Whitney U-test.

RESULTS

Except group IV, there was a statistically significant decrease in fluorescence after the application of sealants (P < 0.05). The decrease of LFpen readings in the opaque sealant groups was more significant than the clear sealant groups (P < 0.05). But for both sealants, the difference between phosphoric acid and Clearfil S3 Bond groups was nonsignificant (P > 0.05).

CONCLUSIONS

There was a statistically significant decrease in fluorescence for both clear and opaque sealant groups. However, clear sealant with Clearfil S3 Bond does not influence the LFpen readings.

Clinical performance of a new laser fluorescence device for detection of occlusal caries lesions in permanent molars

OBJECTIVES

To determine the clinical performance of a laser fluorescence device (DIAGNOdent pen, KaVo) to discriminate between different occlusal caries depths (D(0)-D(1-4); D(0-2)-D(3,4)) in permanent molars.

METHODS

In this prospective, randomized two-centre-study 120 sound/uncavitated carious sites in 120 patients were measured after visual and radiographic caries assessment. In cases of operative intervention (n=86), the lesion depths after caries removal were recorded (reference). In cases of preventive intervention (n=34), the sites were reassessed visually/radiographically after 12 months to verify the status assessed before (reference). The discrimination performance was determined statistically (Mann-Whitney test, Spearman's rho coefficient, and areas under the receiver operating characteristic curves (AUCs)). Sensitivities (SE) and specificities (SP) were plotted as a function of the measured values and cut-off values for the mentioned thresholds suggested.

RESULTS

Sound sites (n=13) had significantly minor fluorescence values than carious sites (n=107) (P<0.0001) as had sites with no/enamel caries (n=63) compared to dentinal caries (n=57). The AUCs for the same discriminations were 0.92 and 0.78 (P<0.001). For the D(0)-D(1-4) threshold, a cut-off at a value of 12 (SE: 0.88, SP: 0.85) and for the D(0-2)-D(3,4) threshold at 25 (SE: 0.67, SP: 0.79) can be suggested. A moderate positive correlation between the measurements and the caries depths was calculated (rho=+0.57, P=0.01).

CONCLUSION

Within this study, the device's discrimination performance for different caries depths was moderate to very good and it may be recommended as adjunct tool in the diagnosis of occlusal caries.

Effect of dietary habits on laser fluorescence values of visually sound occlusal surfaces among Finnish schoolchildren

AIM

This study was designed to ascertain whether schoolchildren with unfavourable dietary habits have higher values for laser fluorescence on clinically sound occlusal tooth surfaces than do those who have favourable dietary habits.

DESIGN

The study was conducted in two phases. In the first phase, 462 children aged 13-14 years answered a questionnaire on dietary habits. The children were ranked according to a total score based on the presumed harmfulness of their dietary habits. One hundred children with the lowest and highest dietary scores were invited to the second phase of the study consisting of a visual examination, laser fluorescence scanning of premolars and molars, and an oral self-care questionnaire.

RESULTS

Seventy-four and 76 children with favourable and unfavourable habits, respectively, were examined. A total of 1221 sound occlusal surfaces were scanned. Children with unfavourable dietary habits had higher median laser fluorescence values than did those with favourable habits (P < 0.0246). The effect of dietary habits was strongest in molars.

CONCLUSION

High laser fluorescence values on several clinically sound occlusal surfaces of a child may indicate unfavourable dietary habits.

Comparison of two laser fluorescence devices for the detection of occlusal caries in vivo

Laser fluorescence measurements have been shown to be well suited for caries diagnosis. The aim of this study was to compare two laser fluorescence devices and to correlate the respective values with the visual and radiographic assessment and with the extent of the carious lesion. Ninety-four clinically non-cavitated occlusal carious lesions in the premolars and molars of 82 patients were examined. Laser fluorescence values on the surface were measured with a conventional laser fluorescence system and a novel laser fluorescence pen device. When operative intervention at a site was indicated, the extent of caries was determined after its removal. Readings obtained with both systems were significantly different with an interdevice factor of 0.64. Sensitivity and specificity for operative care were 92.6% and 53.7%, respectively, for the conventional, and 88.9% and 53.7%, respectively, for the pen device. For both devices, a correlation between laser fluorescence values and the visual and radiographic assessment and with the extent of the lesion was shown. The study indicates that the novel laser fluorescence device seems to be suitable for occlusal caries diagnosis. However, proposed guidelines for the clinical use of laser fluorescence readings of the conventional device cannot be transferred to the novel pen system.