Occlusal caries detection with KaVo DIAGNOdent and radiography: an in vitro comparison

Clinical diagnosis of fissure caries with conventional and laser-induced fluorescence techniques

We studied the in vivo validity of dentinal fissure caries diagnosis by visual examination, bitewing radiography, and use of a laser-induced fluorescence device (DIAGNOdent). A total of 144 and second molars with macroscopically intact occlusal surfaces in 41 Chinese young adults were examined visually, by bitewing radiography, and by DIAGNOdent. Visual examination after pit and fissure opening was used as the reference standard. The sensitivity and specificity of detecting caries that had extended into the dentin were, respectively, 0.89 and 0.44 by visual detection of opacity or discoloration after air drying, 0.13 and 1.00 by bitewing radiography to detect radiolucency extending into the dentin, and 0.70 and 0.84 by DIAGNOdent testing with a cut-off score of 40. Caries detection by a combination of visual examination and DIAGNOdent had a sensitivity of 0.67 and specificity of 0.94. Receiver operating characteristic analysis showed that this combined approach was superior to the other methods.

In Vivo Evaluation of DIAGNOdent for the Quantification of Occlusal Dental Caries

There is a weak correlation between DIAGNOdent readings and carious lesion depth and volume. Based on the current study, the appropriate DIAGNOdent cut-off point to detect carious lesions reaching the DEJ or beyond is between 35 and 40.

The management of incipient or suspicious occlusal caries: a decision-tree analysis

OBJECTIVE

To perform a comprehensive decision-tree analysis for the management of the suspicious/incipient occlusal lesion on a molar tooth.

METHODS

A quantitative decision tree was constructed to assess the expected utility value of three global strategies to dentally manage the incipient or suspicious occlusal carious lesion.

RESULT

A preventive strategy offered an optimal expected utility value (0.98 utile) compared with the other two strategies of visual inspection (0.84 utile) or referring to one of four diagnostic tests (0.74-0.82 utile).

CONCLUSION

Although the general conclusion of this analysis agrees with current recommendations, this analysis offers a more complete mathematical model that provides a unified value for each strategy (i.e. expected utility value) thus allowing for complex quantitative comparison between strategies. This paper provides a specific example of how decision-tree analysis can be a powerful tool in guiding dental practice.

Clinical evaluation of polypropylene glycol-based caries detecting dyes for primary and permanent carious dentin

OBJECTIVE

The aim of this study was to compare the clinical efficacy of new caries detecting dye Caries Check Blue (CCB) with Caries Check (CC) and Caries Detector (CD) using a laser fluorescence device (DIAGNOdent).

METHOD

Primary and permanent teeth with dentin caries were stained with polypropylene glycol (MW=300) based new caries detecting dyes CCB, CC, or propylene glycol (MW=76) based CD. In the CCB and CC groups, stained dentin was completely removed. In the CD groups, pink-stained dentin was retained according to the manufacturers' instructions. Cavities before and after caries removal were measured with the DIAGNOdent. Data were analyzed using ANOVA and Fisher's PLSD multiple comparison test at alpha=0.05. Regression analyses were performed between DIAGNOdent readings and scores obtained from the clinical parameters.

RESULTS

The DIAGNOdent readings after caries removal were: primary-CCB (13.2+/-10.4), primary-CC (14.3+/-16.7), primary-CD (9.0+/-5.2), permanent-CCB (22.7+/-13.4), permanent-CC (10.6+/-6.8) and permanent-CD (9.7+/-9.0). Significant differences were identified between the permanent-CCB and all other groups. Correlation coefficients between DIAGNOdent readings and clinical parameters were low.

CONCLUSIONS

When dentin stained with Caries Check Blue or Caries Check was completely removed, the DIAGNOdent readings were higher than those recorded when palely-stained pink dentin was retained with the Caries Detector, with significant difference observed for the permanent-CCB group. Caries Check Blue may be used clinically to avoid excessive removal of caries-affected or sound dentin in permanent teeth but not in primary teeth.

Raman imaging of carious lesions using a hollow optical fiber probe

Raman spectroscopy using a hollow optical fiber probe with a glass ball lens at the distal end is proposed for detection of early caries lesions. Raman spectroscopy on carious lesions of extracted teeth showed that the probe enables measurement with a high signal-to-noise ratio when combined with a ball lens with a high refractive index. The proposed probe and lens combination detects changes in Raman spectra caused by morphological differences between sound and carious enamel. We also obtained a high-contrast image of an early carious lesion by scanning the tooth surface with the probe.

Caries detection with DIAGNOdent and ultrasound

OBJECTIVE

The objective of this study was to evaluate the repeatability of 2 nondestructive caries detection methods, ultrasound (ULS) and DIAGNOdent, for the detection of approximal caries lesions, and to evaluate 2 tips provided for the DIAGNOdent.

STUDY DESIGN

White/brown-spot lesions (n = 42) were captured by a digital camera, and measured by test methods and confocal laser scanning microscope (CLSM). Intra- and inter-observer reliability, accuracy, and Cohen's kappa and Spearman's rho statistics were used.

RESULTS

At DIAGNOdent, intra-observer agreements were 78.5%, 66.7% for A tip and 59.5%, 47.6% for B for 2 examiners, respectively. Accuracy of both tips was 50% for the first examiner; 45.3% for A and 47.6% for the B tip for the second examiner. All ULS measurements were accurate, reliable, and positively and significantly correlated between examiners.

CONCLUSION

The A tip of the DIAGNOdent was found to be better than the B tip for the detection of enamel caries. All DIAGNOdent and ULS measurements were positive and significantly correlated for both examiners. Both methods demonstrated high repeatability and accuracy.

Clinical performance of a diode laser fluorescence device for the detection of occlusal caries in primary teeth

OBJECTIVES

To correlate the DIAGNOdent readings (LF) with those of direct visual (DV) examination, indirect visual (IDV) examination, bitewing radiography (BWR), and pit and fissure opening (PFO) for the detection of occlusal caries in primary teeth; to determine the validity of this device using PFO as reference; and to evaluate its reliability.

METHODS

Two calibrated operators examined 130 teeth with 405 examination sites using DV, IDV and radiographic examinations, and LF. Of the 405 sites, 155 were visually scored for caries after pit and fissure opening.

RESULTS

Pit and fissure opening was found to significantly correlate with all methods (rhoLF = 0.48, rhoBWX = 0.48, rhoDV = 0.44, rhoIDV = 0.41). For enamel lesions, higher sensitivity (0.76) was found with DV, while higher specificity (0.88) with the LF. For lesions into dentin, however, higher sensitivity (0.78) was found with the LF, while higher specificity (0.98) with the BWR. The device's accuracy was found to be 0.61 for enamel lesions, while for lesions into dentin 0.70, and its reliability was excellent (ICC = 0.97).

CONCLUSION

The LF device presented high reliability in the detection of occlusal caries in primary teeth and its performance was similar to DV and radiographic examinations.

In vitro detection and quantification of enamel and root caries using infrared photothermal radiometry and modulated luminescence

Artificially created demineralized and remineralized carious lesions on the root and enamel of human teeth were examined by photothermal radiometry (PTR) and modulated luminescence (LUM). Fourteen extracted human teeth were used and a lesion was created on a 1 mmx4 mm rectangular window, spanning root to enamel, using a lactic acid-based acidified gel to demineralize the tooth surface. The lesion was then exposed to a remineralization solution. Each sample was examined with PTR/LUM on the root and enamel before and after treatment at times from 1 to 10 (5 on root) days of demineralization and 2 to 10 days of remineralization. Ten-day (5 on root) demineralized samples were remineralized. After completing all the experiments, transverse microradiography (TMR) analysis was performed to compare and correlate the PTR/LUM signals to the depth of lesions and mineral losses. The PTR and LUM amplitudes and phases showed gradual and consistent changes with treatment time. In this study, TMR showed good correlation coefficients with PTR and LUM. It was also found that the length of the treatment time did not correlate very well to any technique, PTR/LUM or TMR, which implies a significant degree of inhomogeneity of the demireralization and remineralization rates in each and every tooth.

The influence of zero value subtraction on the performance of a new laser fluorescence device for approximal caries detection

The aim of this study was to assess the influence of the zero value subtraction on the performance of laser fluorescence (LFpen) for approximal caries detection. Three areas (cuspal, middle and cervical) of both mesial and distal buccal surfaces of 78 permanent molars were assessed using both wedge-shaped (WDG) and tapered wedge-shaped (TWDG) tips. With the addition of the average, one cut-off value for each area was obtained and the performance was assessed. The areas under the receiver operating characteristics (ROC) curve, specificity, sensitivity and accuracy with and without the zero value subtraction were calculated. The McNemar test revealed a statistically significant difference for specificity at thresholds D(1), D(2) and D(3) (WDG) and D(1) and D(2) (TWDG) when the zero value subtraction was not performed. Influence of the zero value subtraction on the LFpen performance was observed for approximal caries detection. However, when modified cut-off values were used, the zero value subtraction could be eliminated.

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.

Evaluation of selective caries removal in deciduous teeth by a fluorescence feedback-controlled Er:YAG laser in vivo

This study investigated the ability and efficacy of an Er:YAG laser with a fluorescence feedback system for caries removal in deciduous teeth. Seventy-nine carious lesions were excavated using a fluorescence-controlled Er:YAG laser. Endpoint of treatment was defined by emission of fluorescence from the dentine surface below the pre-selected threshold level of 7 units and the subsequent termination of Er:YAG laser radiation. Dentine samples were obtained from the cavity floor, and viable counts of both Streptococcus mutans and Lactobacilli, expressed as colony forming units (log CFU), were evaluated. Preparation time was recorded to assess efficacy of the treatment procedure. S. mutans and/or Lactobacilli were found in 25 out of 79 lesions. Regarding the counts for S. mutans and Lactobacilli, the median log CFU was 0 (min, 0; max, 5.5) and 0 (min, 0; max, 6), respectively, with 2.4% of all samples yielding more than 100 CFU S. mutans and 4.8% yielding more than 100 CFU Lactobacilli. In 8 out of 79 cases, laser excavated cavities were not judged being caries-free using the conventional tactile criterion for assessing caries tissue. Focussing on these teeth, the median log CFU was 0 (min, 0; max, 0.5) for S. mutans and 0 (min, 0; max, 1.6) for Lactobacilli. The mean time for treatment was 2.3+/-1.2 min. Of the children, 93.8% rated the laser treatment to be comfortable. The study indicates that the fluorescence feedback-controlled Er:YAG laser might be an appropriate device for caries removal in children using the suggested threshold level of 7 units.

The application of ozone in dentistry: a systematic review of literature

OBJECTIVES

(1) To systematically review the clinical application and remineralization potentials of ozone in dentistry; (2) To summarize the available in vitro applications of ozone in dentistry.

SOURCES

Ovid MEDLINE, CINAHL, etc. (up to April 2007).

STUDY SELECTION

In vitro or in vivo English language publications, original studies, and reviews were included. Conference papers, abstracts, and posters were excluded.

RESULTS

In vitro: Good evidence of ozone biocompatibility with human oral epithelial cells, gingival fibroblast, and periodontal cells; Conflicting evidence of antimicrobial efficacy of ozone but some evidence that ozone is effective in removing the microorganisms from dental unit water lines, the oral cavity, and dentures; Conflicting evidence for the application of ozone in endodontics; Insufficient evidence for the application of ozone in oral surgery and implantology; Good evidence of the prophylactic application of ozone in restorative dentistry prior to etching and the placement of dental sealants and restorations. In vivo: Despite the promising in vitro evidence, the clinical application of ozone in dentistry (so far in management of dental and root caries) has not achieved a strong level of efficacy and cost-effectiveness.

CONCLUSIONS

While laboratory studies suggest a promising potential of ozone in dentistry, this has not been fully realised in clinical studies to date. More well designed and conducted double-blind randomised clinical trials with adequate sample size, limited or no loss to follow up, and carefully standardised methods of measurement and analyses are needed to evaluate the possible use of ozone as a treatment modality in dentistry.

Investigation of in vitro dental erosion by optical techniques

Nitrogen laser-induced fluorescence (LIF) and tungsten halogen lamp excited diffuse reflectance spectra were recorded in 350- to 700-nm range on a miniature fiber-optic spectrometer from in vitro premolar tooth during various stages of artificial erosion with 36% phosphoric acid. Both the LIF spectral intensity and the diffuse reflectance intensity gradually increased during tooth erosion. The LIF spectra were analyzed by curve fitting using Gaussian spectral functions to determine the true contribution of different bands in the spectra during erosion. Thus, the broad bands at 440 and 490 nm in the LIF spectra of sound enamel were resolved into four peaks centered at 409.1, 438.1, 492.4 and 523.1 nm and of sound dentin into peaks at 412.0, 440.1, 487.8 and 523.4 nm. The F410/F525 ratios derived from curve-fitted Gaussian peak amplitudes and curve areas were found to be more sensitive to erosion as compared to the diffuse reflectance ratio R500/R700 or the raw LIF spectral ratio F440/F490.

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.

Reproducibility of DIAGNOdent 2095 and DIAGNOdent Pen measurements: results from an in vitro study on occlusal sites

The aim of this in vitro study was to investigate the intra- and interdevice reproducibility of the DIAGNOdent 2095 (DD2095) and the new DIAGNOdent Pen (DDPen) on non-cavitated occlusal caries sites. Altogether, 241 sites on 90 molars were inspected twice with both devices and by four examiners. The intra/interdevice reproducibilities were assessed by means of the intraclass correlation coefficient (ICC) as well as by the range of the 95% limits of agreement of Bland & Altman. Additionally, a linear mixed-effects model was fitted with fixed effects for the visual scores and the devices used and random effects for occlusal sites and examiners within each measurement site. In result, the following values were determined for the intradevice reproducibility: DD2095: ICC 0.89, range 42.3; and DDPen: ICC 0.88, range 49.3. The interdevice reproducibility was found to be in the same order of magnitude (ICC 0.82, range 53.7). The comparison between both devices indicated significantly lower mean values for the DDPen. The estimates of the linear model show that there is a high variation between the sites that cannot be explained by the fixed effects. In conclusion, both devices showed an imperfect reproducibility, which indicate the usage as adjunct tool only in clinical practice.

Effects of composite fissure sealants on IR laser fluorescence measurements

The influence of composite fissure sealants on caries detection with IR laser fluorescence measurements should be assessed. Thirty-five extracted human teeth with 105 initial carious lesions were included. Six groups containing 15 lesions each were sealed with either a clear or a white version of three sealants. Group 7 was sealed with an experimental nanofilled material. Occlusal surfaces were irradiated by a diode laser (<1 mW, 655 nm). Fluorescence was measured before and after acid etching, directly and 1 week after application of the sealants. Values significantly increased after etching (p < 0.05). Compared to initial measurements, values decreased after sealing with the white materials (p < 0.05). There was no difference between values before and after sealing with the clear and the experimental materials (p > 0.05). All values were reproducible. The study indicates that it might be possible to monitor caries activity under clear or nanofilled fissure sealants by means of laser fluorescence.

Detection of interproximal demineralized lesions on human teeth in vitro using frequency-domain infrared photothermal radiometry and modulated luminescence

Frequency-domain photothermal radiometry (FD-PTR or PTR) is used to detect mechanical holes and demineralized enamel in the interproximal contact area of extracted human teeth. Thirty-four teeth are used in a series of experiments. Preliminary tests to detect mechanical holes created by dental burs and 37% phosphoric acid etching for 20 s on the interproximal contact points show distinct differences in the signal. Interproximal contact areas are demineralized by using a partially saturated acidic buffer system. Each sample pair is examined with PTR before and after micromachining or treating at sequential treatment periods spanning 6 h to 30 days. Dental bitewing radiographs showed no sign of demineralized lesion even for samples treated for 30 days. Microcomputer tomography (micro-CT), transverse microradiography (TMR), and scanning electron microscopy (SEM) analyses are performed. Although micro-CT and TMR measured mineral losses and lesion depths, only SEM surface images showed visible signs of treatment because of the minimal extent of the demineralization. However, the PTR amplitude increased by more than 300% after 80 h of treatment. Therefore, PTR is shown to have sufficient contrast for the detection of very early interproximal demineralized lesions. The technique further exhibits excellent signal reproducibility and consistent signal changes in the presence of interproximal demineralized lesions, attributes that could lead to PTR as a reliable probe to detect early interproximal demineralization lesions. Modulated luminescence is also measured simultaneously, but it shows a lower ability than PTR to detect these interproximal demineralized lesions.

Laser fluorescence measurements compared to electrical resistance of residual dentine in excavated cavities in vivo

It has been suggested that laser fluorescence close to the dental pulp shows higher values than more distant measurements. The aim of this study was to assess fluorescence on the cavity floor and to correlate these measurements with electrical resistance as a measure of residual dentine thickness. Thirty carious lesions were excavated with a bur. The endpoint of caries removal was determined by visual, tactile and auditory means. Fluorescence was measured with the Diagnodent device and with the fluorescence feedback system of a therapeutic Er:YAG laser. Electrical resistance of the residual dentine (Prepometer units, PU) was measured with a proprietary device. Significant differences were observed between the fluorescence systems (p < 0.05). For Diagnodent, a decrease of electrical resistance of the residual dentine resulted in an increase of the fluorescence values of 2.99 units/PU (95% CI = 2.00-3.97) and an increase of 0.30 units/PU (95% CI = 0.19-0.40) for the fluorescence feedback system. For zero electrical resistance, a predicted maximum value of 51.5 units (95% CI = 41.3-61.7) was calculated for the Diagnodent and 5.1 units (95% CI = 4.1-6.2) for the feedback system. The study indicates that using the suggested detection cut-off with the Diagnodent device may be not suited to assess the endpoint of caries removal close to the dental pulp. Employing the Key Laser III, values up to 6 units might be caused solely by close proximity to the pulp, which should be considered when caries removal by laser is controlled by laser fluorescence feedback.

In vitro quantification of smooth surface caries with DIAGNOdent and the DIAGNOdent pen

OBJECTIVE

A new generation of the laser fluorescence device, DIAGNOdent, for caries detection and quantification has been introduced recently. It is the DIAGNOdent pen. The aim of this study was to compare the validity and reliability of both laser-based devices, DIAGNOdent and the DIAGNOdent pen, in quantifying smooth surface caries.

MATERIAL AND METHODS

The material comprised a sample of 52 premolar teeth extracted on orthodontic indication. The teeth were visually sound or had various stages of non-cavitated carious lesions on smooth surfaces. All teeth were photographed and measured with both DIAGNOdent and the DIAGNOdent pen by two examiners independently. The teeth were then sectioned into 300-microm slices and analysed under a microscope for verification of lesion depth. Histopathological analyses were performed by two observers to assess lesion depth, which was classified into five categories ranging from sound to dentinal caries. Reliability and validity of the two devices were evaluated in terms of intra-class coefficients and Spearman rank correlation coefficient, respectively. The relation between measurements performed by DIAGNOdent and the DIAGNOdent pen was analyzed using Pearson's correlation coefficient.

RESULTS

Both DIAGNOdent and the DIAGNOdent pen had excellent intra-observer agreement and acceptable inter-observer agreement. The correlation with histology for DIAGNOdent and the DIAGNOdent pen ranged between 0.47 and 0.57, although the correlation between DIAGNOdent and the DIAGNOdent pen was high.

CONCLUSIONS

In this in vitro study, the new laser fluorescence device, the DIAGNOdent pen, showed similar reliability and validity at quantification of smooth surface caries compared to the conventional DIAGNOdent device. Agreement between DIAGNOdent and the DIAGNOdent pen was excellent.

Evaluation of a new caries detecting dye for primary and permanent carious dentin

OBJECTIVE

This study evaluated the clinical efficacy of a new caries detecting dye using a laser fluorescence device (DIAGNOdent).

METHOD

Primary and permanent teeth with dentin caries were stained with Caries Check (CC), containing 1% acid red in polypropylene glycol (MW=300) or Caries Detector (CD), containing 1% acid red in propylene glycol (MW=76). Primary-CC, primary-CD, permanent-CC and permanent-CD groups were prepared. In the CC groups, stained dentin was completely removed. In the CD groups, pink-stained dentin was retained according to the manufacturers' instructions. Cavities before and after caries removal were measured with the DIAGNOdent. Data were analyzed using ANOVA and Fisher's PLSD multiple comparison test at alpha=0.05. Regression analyses were performed between DIAGNOdent readings and scores obtained from the clinical parameters.

RESULTS

For all groups, there were no significant differences in the DIAGNOdent readings before treatment. The DIAGNOdent readings after caries removal were: primary-CC (16.0+/-17.6), primary-CD (9.6+/-5.2), permanent-CC (11.0+/-7.0) and permanent-CD (7.1+/-3.8). Significant differences were identified between the permanent-CC and primary-CD, and permanent-CC and permanent-CD subgroups but not for the primary subgroups. Correlation coefficients between DIAGNOdent readings and clinical parameters were low.

CONCLUSIONS

When dentin stained with Caries Check was completely removed, the DIAGNOdent readings were higher than those recorded when palely-stained pink dentin was retained with the Caries Detector, with significant difference observed for the permanent teeth. Caries Check may be used clinically to avoid excessive removal of caries-affected or sound dentin in permanent teeth but not in primary teeth.

Light Intensity Evaluation of Laser-induced Fluorescence after Caries Removal Using an Experimental Caries Staining Agent

OBJECTIVE

The purpose of this study was to evaluate the intensity of fluorescent light reflected from cavity wall dentin, after dentin stained by an experimental caries detecting liquid was removed.

BACKGROUND DATA

The conventional caries detecting liquid tends to penetrate dentin too deeply. On the other hand, DIAGNOdent has gradually gained recognition and established itself as a caries detection device using a laser beam.

METHOD

An experimental caries staining liquid or the conventional caries staining liquid was applied in the same cavity to observe for differences in dye penetration. Intensity of fluorescence reflected from treated dentin was measured by DIAGNOdent.

RESULTS

The mean DIAGNOdent value after removing the tooth substance stained by the experimental liquid was 17.9+/-4.1, compared with 7.7+/-2.7 by conventional one.

CONCLUSION

Light intensity evaluation of laser-induced fluorescence suggested that the experimental caries detecting liquid did not penetrate the dentin which should be preserved, hence avoiding overtreatment.

The evidence supporting alternative management strategies for early occlusal caries and suspected occlusal dentinal caries

OBJECTIVE

To assess the strength of the evidence describing the effectiveness of alternative strategies to the detection and management of early occlusal caries and suspected occlusal dentinal caries.

METHODS

Nine detection and intervention decision points were identified as being central to the management of early occlusal caries and suspected occlusal dentinal caries, or suspicious areas. For each decision point, the evidence for effectiveness was assessed, using existing systematic reviews when available, and nonsystematic review methods when necessary.

RESULTS

For the 2 detection decisions (early occlusal caries and suspicious areas) the strength of the evidence was weak. Accuracy in detecting early occlusal caries was extremely variable within and across detection methods. Approximately 50% of suspicious areas identified had dentinal caries. The strength of the evidence for effectiveness of nonsurgical approaches for the management of early occlusal caries was weak for all 3 management strategies examined (doing nothing, sealants, remineralization). This evidence suggested that sealants were highly effective, with remineralization reflecting moderate effectiveness. For the management of suspicious areas, the strength of the evidence was still weaker and reflected the same relative effectiveness. For the surgical management strategy for suspicious areas, operative treatment, the evidence was strong and reflected high effectiveness for preventive resin restorations, but no evidence was available for minimally invasive techniques.

CONCLUSION

Identification methods for early occlusal caries are not accurate. The strength of the evidence for effectiveness of nonsurgical management strategies for early occlusal caries is at best, weak. The available evidence suggests that sealing both enamel caries and suspected occlusal dentinal caries is the most effective management approach if subsequent maintenance of the sealed surfaces can be assured.

Caries detection and diagnosis: Novel technologies

Recent years have seen an increase in research activity surrounding diagnostic methods, particularly in the assessment of early caries lesions. The drive for this has come from two disparate directions. The first is from the dentifrice industry who are keen to develop techniques that would permit caries clinical trials (CCTs) to be reduced in duration and subject numbers to permit the investigation of novel new anti-caries actives. The second is from clinicians who, armed with the therapies to remineralise early lesions are now seeking methods to reliably detect such demineralised areas and implement true preventative dentistry. This review examines novel technologies and the research supporting their use. Techniques based on visual, optical, radiographic and some emerging technologies are discussed. Each have their benefits although systems based on the auto-fluorescence (such as QLF) of teeth and electrical resistance (such as ECM) seem to offer the most hope for achieving reliable, accurate detection of the earliest stages of enamel demineralisation.

Validity and reproducibility of different combinations of methods for occlusal caries detection: an in vitro comparison

This study assessed the validity and reproducibility of different combinations of occlusal caries detection methods: visual examination (VE), laser fluorescence (LF) and radiographic examination (RE). Intra- and interexaminer reproducibilities were also assessed. Forty-seven extracted human molars were used and 121 sites, either suspected or not to be carious, were chosen. Occlusal surfaces were examined by 8 volunteers, assigned to three groups according to their level of knowledge and clinical experience on dental practice: group I, undergraduate students; group II, postgraduate students; group III, professors. Three combinations of methods were tested: A: VE+LF, B: VE+RE, C: VE+LF+RE. The examiners scored the sites using ranking scales and chose a final score based on their clinical experience. The gold standard was determined by histological examination of the sites. In general, LF and RE yielded poorer results than the combinations of methods. For combination A, group III showed the highest sensitivity, while group II showed the highest specificity. For combination B, group II showed moderate sensitivity whereas groups I and III exhibited low sensitivities; all groups of examiners reached substantial specificity. For combination C, all groups exhibited moderate sensitivity and substantial specificity. Interexaminer reproducibility ranged from fair to moderate for combinations A and C, while for combination B kappa values indicated moderate interexaminer reproducibility. It may be concluded that individual exams presented inferior performance than the conjunction of them. Combination C (VE+LF+RE) resulted in the best accuracy for all groups. The knowledge background of the examiners influenced their ability to detect caries lesions and affected interexaminer reproducibility.

Effect of Placing a Clear Sealant on the Validity and Reproducibility of Occlusal Caries Detection by a Laser Fluorescence Device: An in vitro Study

The principal aim of this in vitro study was to assess the validity and reproducibility of the detection of occlusal caries using laser fluorescence (LF), prior to and following the placement of a clear fissure sealant. It also aimed to compare the manufacturer's standard cut-off recommendations with those published for in vitro studies and to compare the validity and reproducibility of LF with clinical visual examination (CVE) for the detection of occlusal caries under sealants. Three clinicians independently examined visually and with LF 37 extracted teeth (25 molars, 12 premolars), with a range of clinical caries from apparently sound to cavitated dentinal caries. Examinations were conducted under dental surgery conditions. Subsequently, the teeth were serially sectioned to provide the validating criterion. Following placement of the sealant, the specificity generally increased but there was an associated loss of sensitivity, at both the D1 (enamel and dentine) and D3 (dentine) diagnostic thresholds. The LF readings were significantly lower after placement of the sealant (p<0.05). The manufacturer's recommended cut-offs appear to be the most appropriate to use. The CVE had superior validity and reproducibility when compared to LF. Overall, the placement of a clear sealant does influence the detection of caries by LF but does not prevent the detection of caries by this method.

Occlusal caries diagnosis in permanent teeth: an in vitro study

The reduction in caries prevalence has not occurred uniformly for all dental surfaces. As the occlusal surfaces are still the most likely sites for the development of lesions, new methods of diagnosis are still being evaluated. This study compared a laser fluorescence (LF) system (DIAGNOdent) with the Ekstrands visual system for in vitro detection of occlusal caries. A total of 57 extracted molars with macroscopically intact occlusal surfaces were selected. Two-examiners assessed 110 sites by visual inspection (VI) and LF. After ten days from the first measurement, all teeth were re-evaluated through the same methods by each examiner. Caries extension was histologically assessed (X 40). The methods were compared by means of sensitivity, specificity, intra- and inter-examiner reproducibility and area under the ROC curve. The kappas test showed good intra- and inter-examiner reproducibility for both methods. VI and LF showed similar sensitivities for both examiners, however, VI showed higher specificities than LF. The overall analysis, as demonstrated by the area under the ROC curve, showed that VI had a better performance than the LF device. It was concluded that the Ekstrands visual system is more reliable than the LF device. LF should be considered only as an adjuvant for occlusal caries diagnosis.

Utility of radiology, laser fluorescence, and transillumination

This article provides readers with an overview of the latest developments in caries detection using radiology, laser fluorescence, and transillumination. Different imaging techniques, methods to assess diagnostic accuracy, and factors affecting the diagnostic accuracy of imaging in film and digital receptors are discussed. In addition, the DIAGNOdent and DIFOTI devices are introduced as possible supplemental techniques for detecting incipient and hidden carious lesions.

Early caries imaging and monitoring with near-infrared light

Enamel is highly transparent in the near infrared (NIR); therefore, this region of the electromagnetic spectrum is suited ideally for the development of new optical diagnostic tools for the detection and imaging of early dental caries. This article discusses the NIR optical properties of sound and demineralized dental enamel and the potential use of polarization sensitive optical coherence tomography and NIR transillumination for the imaging of dental caries.

Contemporary treatment of incipient caries and the rationale for conservative operative techniques

This article provides evidence to support the use of more conservative cavity preparation techniques with adhesive restorative resins. The authors discuss the issue of conservative operative techniques related to hidden or occult caries. The support for contemporary technology also concerns methods of caries detection and the role of magnification, caries risk assessment of the patient, conservative caries management, instrumentation, materials, and techniques.

Criteria for a Diagnosis of Caries through the DIAGNOdent

OBJECTIVE

The aim of this study was to investigate the correlation between the demineralization depth measured by dental computed tomography (CT) and the measured value from a non-destructive dental caries diagnosis with a laser.

METHODS

Optimal cut-off points were obtained for enamel and dentin caries, from the measured levels from a dental caries diagnosis with a laser, to investigate the clinical usefulness of a diagnosis using a laser. Using human teeth, the demineralization depth was measured and the caries were diagnosed by a dental caries diagnosis with a laser.

RESULTS

The optimal cut-off point was investigated for accuracy, sensibility, and specificity, which were calculated from the results. These results demonstrated the correlation between the measured values and demineralization depth in both the pit and fissure caries and smooth surface caries. The optimal cut-off points were found to be 16-21 in the fissure caries and 9-11 in the smooth surface caries.

Measurement of the severity of natural smooth surface (interproximal) caries lesions with polarization sensitive optical coherence tomography

BACKGROUND AND OBJECTIVES

Previous studies have demonstrated that polarization sensitive optical coherence tomography (PS-OCT) can be used to image early dental caries. The purpose of this study was to compare the measured reflectivity of natural caries lesions found on smooth surfaces (interproximal lesions) with the mineral loss measured using digital microradiography (DM) in order to determine if PS-OCT can be used as a non-destructive method to measure the severity of dental decay and resolve the internal structure of caries lesions.

MATERIALS AND METHODS

A PS-OCT system operating at 1,310 nm was used to acquire polarization resolved images of natural white spot lesions and pigmented lesions on the smooth surfaces of extracted teeth. The integrated reflectivity from lesion areas was compared to polarized light microscopic images (PLM) and to the integrated mineral loss from the same lesion area measured using high resolution DM.

RESULTS

The frequently complex internal structure of caries lesions could be resolved with PS-OCT. Such structural information is potentially useful for determining whether or not the lesion is active and progressing or whether it has become arrested and remineralized and does not require intervention. There was a strong correlation between the integrated mineral loss of the caries lesions measured using DM and the integrated reflectivity in the perpendicular polarization axis of the PS-OCT system.

CONCLUSIONS

The integrated reflectivity in the perpendicular polarization channel can be used to represent the severity of demineralization in natural early caries lesions. Therefore, PS-OCT has considerable potential as a non-destructive clinical probe of early caries lesions to assess their severity, monitor their progression over-time and potentially assess lesion activity.

Clinical effectiveness of laser fluorescence, visual inspection and radiography in the detection of occlusal caries

The aim of this in vivo study was to compare a laser fluorescence (LF) device with Ekstrand's visual scoring system and radiographic assessment for detection of occlusal caries. Thirty-eight adults aged 19-35 years participated in the study; a total of 57 third molars with macroscopically intact occlusal surfaces were selected. Two examiners assessed 110 sites by visual inspection (VI), bitewing radiography (BW) and LF. Teeth were then extracted and caries extent assessed by histology. The detection methods were compared by means of sensitivity, specificity, inter-examiner reproducibility (kappa statistics) and area under the ROC curve. VI and LF had similar (p > 0.05) and superior sensitivities than BW (p < 0.05). VI and BW showed similar specificities, which was superior to LF. The inter-examiner reproducibility was good for VI and BW and moderate for LF. The area under ROC curves showed that VI was better than LF. It was concluded that Ekstrand's visual scoring system is the most valid method for caries diagnosis. LF should be considered an adjunct to caries diagnosis.

Caries risk assessment: methods available to clinicians for caries detection

It is hypothesized that occlusal lesions are initiated on the fissure walls and can therefore be obscured by sound superficial tissue. Additionally, there is evidence that one effect of regular use of fluorides is greater opacity of enamel, which may obscure underlying lesions in dentin, the so-called 'hidden lesions'. Dental radiographs are inadequate for detecting decay in the occlusal surfaces until the lesion is well advanced through the enamel and into the dentin. The clinician relies on visual observation of texture and discoloration, clinical judgment based upon experience, and on tactile sense by probing with an explorer. An objective detection method to complement the traditional visual assessment is used by the clinician for arriving at clinical decisions on the management of the carious lesion: whether invasive therapy or a more conservative, noninvasive approach. Objective and reliable longitudinal monitoring of the lesion's response to preventive measures allow the selection of an appropriate therapy before the lesion progresses to the stage where invasive treatment is required. This paper discusses the problem of the lack of appropriate clinical methods for the detection and quantification of carious lesions. A few commercially available methods are described (the quantitative light-induced fluorescence method, the DIAGNOdent device, and electrical caries monitor) and some new techniques mentioned.

The influence of toothpastes and prophylaxis pastes on fluorescence measurements for caries detection in vitro

The aim of this study was to test the influence of toothpaste and prophylaxis paste remnants as well as powder remnants on DIAGNOdent readings. A total of 68 sites on the occlusal surface of human molars were used for this study. After a cleaning procedure, saliva was spread on the tooth surface, dried for 3 s, and DIAGNOdent (DD) values were measured. After these measurements were performed, 500 mg of the toothpaste or prophylaxis paste was taken and the occlusal surface was cleaned for 3 s with a slow rotating contra-angle handpiece. The paste was then rinsed off with the 3-in-1 syringe for 3 s using water with air. The DD measurements were taken again and the rinsing for 3 s and fluorescence measurements were repeated. The procedure with the powder using the PROPHYflex 2 was, in principle, the same. Whereas only small differences could be detected on sound surfaces, there was a distinct influence on decayed surfaces. It could be concluded that when the DIAGNOdent device is used in practice and special care in rinsing after cleaning is not taken, it is possible that false readings are registered.

Detection of Subgingival Calculus With a Novel LED-Based Optical Probe

BACKGROUND

A recently introduced detection device is designed for objective subgingival calculus diagnosis. The aim of the present study was to assess the possibility of detecting subgingival calculus with this novel LED-based optical probe in vitro.

METHODS

Twenty extracted human teeth with calculus on the root surface were fixed on a translation stage. Measurements on the root surface were carried out in increments of 0.25 mm with an angulation of 0 to 10 degrees , 45 degrees , or 90 degrees to the optical fiber. Teeth were covered either with sodium chloride (NaCl) or blood in order to determine the influence of ambient fluids. Successional areas of positive measurements were defined as "length of positive values" (LPV). The results were compared to the clinical and histological findings.

RESULTS

Clinically and histologically apparent calculus on the root surface was accompanied by positive measurement values. A reduction of the angulation between probe and root surface resulted in shorter LPV when measurements were performed in blood (P <0.05) and longer LPV employing NaCl as the ambient fluid (P <0.05). For both blood and NaCl, sensitivity and/or specificity values decreased when using lower angulations.

CONCLUSION

The optical probe offers the possibility of subgingival calculus detection and may, therefore, be suited to determine the endpoint of root surface instrumentation during non-surgical periodontal therapy.

Influence of Professional Cleaning and Drying of Occlusal Surfaces on Laser Fluorescence in vivo

Three dentists recorded laser fluorescence (LF) values on 117 teeth in 70 patients, in the sequence: (1) moist, uncleaned; (2) dried, uncleaned; (3) moist, cleaned; (4) dried, cleaned. LF values varied significantly with surface status (p < 0.01). The optimal cutoffs were up to 5 units lower on uncleaned, moist surfaces compared to the other states. Drying uncleaned surfaces significantly increased LF readings for dentinal caries (p < 0.01). It was concluded that occlusal surfaces should be clean and dry, for precise longitudinal monitoring of caries with LF as well as for detailed visual inspection, which should precede LF measurements.

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

Manufacturer's advice is to professionally clean teeth before using a laser fluorescence (LF) device in order to avoid false-positive diagnoses. Professional cleaning is not included in routine dental check-ups in children in Finland because it is time-consuming. The aim of our present study was to evaluate the effect of professional cleaning of teeth on LF in children. A total of 642 occlusal surfaces in permanent molars and premolars in 9- to 16-year-olds (n = 46) were first examined visually. After that the first measurements with LF were made without cleaning the teeth. At the same appointment the second measurements were carried out after professional cleaning using a soft rubber cup and either polishing paste or plain water spray. The differences in LF of uncleaned and cleaned teeth were determined separately for teeth with a visual score of 0 (sound) and > 0. In premolars cleaning had no significant effect on LF. In molars, the values increased when the teeth were cleaned, the difference of the measurements being statistically significant in molars with visual score > 0 cleaned with plain water spray. For molars that were cleaned with paste, the differences were not statistically significant. Sealants did not modify the effect of cleaning. As a conclusion cleaning with a rotating instrument and water spray before LF measurements is recommended in teeth with visible plaque. Also in clean teeth, cleaning is advisable in cases where LF readings approach threshold level for operative intervention. The finding that uncleaned teeth gave lower values than cleaned teeth is opposite to what has been suggested.

Ex vivo detection and characterization of early dental caries by optical coherence tomography and Raman spectroscopy

Early dental caries detection will facilitate implementation of nonsurgical methods for arresting caries progression and promoting tooth remineralization. We present a method that combines optical coherence tomography (OCT) and Raman spectroscopy to provide morphological information and biochemical specificity for detecting and characterizing incipient carious lesions found in extracted human teeth. OCT imaging of tooth samples demonstrated increased light backscattering intensity at sites of carious lesions as compared to the sound enamel. The observed lesion depth on an OCT image was approximately 290 microm matching those previously documented for incipient caries. Using Raman microspectroscopy and fiber-optic-based Raman spectroscopy to characterize the caries further, spectral changes were observed in PO4 (3-) vibrations arising from hydroxyapatite of mineralized tooth tissue. Examination of various ratios of PO4 (3-) nu2, nu3, nu4 vibrations against the nu1 vibration showed consistent increases in carious lesions compared to sound enamel. The changes were attributed to demineralization-induced alterations of enamel crystallite morphology and/or orientation. OCT imaging is useful for screening carious sites and determining lesion depth, with Raman spectroscopy providing biochemical confirmation of caries. The combination has potential for development into a new fiber-optic diagnostic tool enabling dentists to identify early caries lesions with greater sensitivity and specificity.

Clinical performance of DIAGnodent in the detection of secondary carious lesions

The diagnostic value of DIAGNOdent in detecting primary occlusal caries has been investigated in many studies, although its use in in vivo detection of secondary caries remains unclear. The aim of this study was to investigate the ability of DIAGNOdent in in vivo detection of secondary caries on teeth with amalgam restorations. The material comprised 51 posterior teeth restored with amalgam material. Bitewing radiographs were taken of all teeth, in accordance with the standard clinical protocol, and analysed by five observers with respect to secondary caries. The restoration margins of each tooth were carefully scanned with DIAGNOdent and the site of the highest reading and its value were registered in a digital picture. The color (stained/unstained) of the restoration margins was also documented. The restoration material was removed and all cavities were examined carefully by two observers together, both visually and by probe. The results showed that the sensitivity and specificity of DIAGNOdent and conventional radiography in detecting secondary caries were 0.60/0.81 and 0.56/0.92, respectively. For DIAGNOdent, 100% of the teeth in the false-positive fraction had stains. Regarding receiver operating characteristic analyses, the Az values were 0.78 and 0.69 for DIAGNOdent and radiography, respectively. We conclude that DIAGNOdent may be used only as an adjunct to conventional methods in detecting secondary caries on teeth with amalgam restorations.

Diagnosis of pit and fissure caries using frequency-domain infrared photothermal radiometry and modulated laser luminescence

Non-intrusive, non-contacting frequency-domain photothermal radiometry (FD-PTR or PTR) and frequency-domain luminescence (FD-LUM or LUM) have been used with 659- and 830-nm laser sources to assess the pits and fissures on the occlusal surfaces of human teeth. Fifty-two human teeth were examined with simultaneous measurements of PTR and LUM and were compared to conventional diagnostic methods including continuous (dc) luminescence (DIAGNOdent), visual inspection and radiographs. To compare each method to the others, sensitivities and specificities were calculated by using histological observations as the gold standard. With the combined criteria of four PTR and LUM signals (two amplitudes and two phases), it was found that the sensitivity of this method was much higher than any of the other methods used in this study, whereas the specificity was comparable to that of dc luminescence diagnostics. Therefore, PTR and LUM, as a combined technique, has the potential to be a reliable tool to diagnose early pit and fissure caries and could provide detailed information about deep lesions. Using the longer wavelength (830-nm) laser source, it has been shown that detection of deeper subsurface lesions than the 659-nm probe provides is possible.

Tooth caries detection by curve fitting of laser-induced fluorescence emission: A comparative evaluation with reflectance spectroscopy

BACKGROUND AND OBJECTIVES

Nitrogen laser-induced fluorescence (LIF) spectra of sound tooth consists of two broad bands centered at 440 and 490 nm, with two apparent side bands on either side. In order to locate the exact peak position of these bands and to effectively utilize the LIF spectral signatures for detection of tooth caries, the LIF spectra were curve-fitted using Gaussian spectral functions and the results were compared with those from diffuse reflectance spectral measurements.

STUDY DESIGN/MATERIALS AND METHODS

The excitation light at 337.1 nm was guided to the sound and caries-affected tooth samples through the central fiber of the fiber-optic probe of a laser-induced fluorescence reflectance spectroscopy (LIFRS) system. Six surrounding fibers of the probe collect tooth fluorescence or diffuse reflectance from the lesion and direct it to a miniature spectrometer. The in vitro spectra were obtained from healthy enamel, dentin, and pulp level tooth caries.

RESULTS

As compared to sound tooth, the caries tooth showed lower fluorescence and reflectance intensities in the 350-700 nm region. The deconvoluted peaks in the LIF spectra of sound tooth were found centered at 403.80, 434.20, 486.88, and 522.45 nm, whereas in the case of pulp level caries, a new peak was observed at 636.78 nm. Curve-fitted parameters, such as peak center, Gaussian curve area, full width at half intensity maximum (FWHM), and their ratios, were also found to vary with the stage of tooth caries. The ratios involving the 435 nm band, such as F405/F435, F435/F490, and F435/F525 ratios derived from curve-fitted areas and amplitudes, were found to be sensitive to discriminate between sound, dentin, and pulp level caries. Among the various diffuse reflectance spectral intensity ratios, the R500/R700 was found to be most sensitive to distinguish between pulp and dentin level caries.

CONCLUSIONS

Nitrogen laser-excited fluorescence spectral studies were found to be more suited for detection of caries lesions. The LIF measurement with spectral analysis, done by curve fitting, outscores the diffuse reflectance methodology and shows the potential to screen different levels of tooth decay in a clinical setting.

Performance of DIAGNOdent for detection and quantification of smooth-surface caries in primary teeth

OBJECTIVES

To evaluate the performance of the laser fluorescence device (DIAGNOdent) for detection and quantification of smooth-surface caries lesions in primary teeth.

METHODS

Seventy-seven approximal surfaces with no caries or with white spot caries lesions without cavitation was selected from 51 primary molars. Laser fluorescence readings were performed and the site of higher value in each surface was indicated. After the readings, the surfaces were cut and the samples were destined for histopathological and cross-sectional microhardness evaluation. ROC analysis was conducted and the area under the ROC curve and the best cut-off points were obtained at D1, D2 and D3 thresholds. With these cut-off values, the sensitivity, specificity and accuracy were calculated at these thresholds. The regression lines of laser fluorescence readings as function of lesion extension, lesion depth and cross-sectional microhardness values were plotted and the Pearson correlation coefficients were obtained.

RESULTS

The best DIAGNOdent performance was obtained at D3 threshold (A(z)=0.90) and the worst performance was achieved at D1 threshold (A(z)=0.82). The correlation was better between the laser fluorescence readings and lesion depth obtained in polarized light microscope examination (r=0.78), than that obtained with the microhardness values (r=-0.57).

CONCLUSION

The laser fluorescence shows a good performance to predict caries lesions extension. Device presents a better correlation with the lesion depth than with mineral loss in smooth-surface caries lesions.

A systematic review of the performance of a laser fluorescence device for detecting caries

BACKGROUND

The DIAGNOdent, or DD (KaVo America, Lake Zurich, Ill.), a device for detecting caries using laser fluorescence, has been growing in popularity during the past three years. Although several evaluations of its diagnostic performance have appeared in the literature, the range of reported performances is extensive.

TYPES OF STUDIES REVIEWED

The authors conducted a systematic review of the literature to assess the diagnostic performance of the DD. Of 115 articles identified in the search, 25 studies were included in the review according to criteria requiring histologic validation and outcomes expressed as sensitivity and specificity values.

RESULTS

For detection of dentinal caries, sensitivity values ranged widely (0.19 to 1.0), although most tended to be high. Specificity values exhibited a similar pattern, ranging from 0.52 to 1.0. In comparison with visual assessment methods, the DD exhibited a sensitivity value that was almost always higher and a specificity value that was almost always lower. The body of evidence is characterized largely by in vitro studies, so that generalization to the clinical setting is uncertain. Because caries thresholds varied substantially across the studies, synthesized estimates of performance were not possible.

CONCLUSIONS AND CLINICAL IMPLICATIONS

The DD clearly is more sensitive than traditional diagnostic methods; however, the increased likelihood of false-positive diagnoses compared with that with visual methods limits its usefulness as a principal diagnostic tool.