The prevalence of questionable occlusal caries: findings from the Dental Practice-Based Research Network

Fissure Sealants or Fluoride Varnish? A Randomized Pragmatic Split-Mouth Trial

This study aimed to compare the clinical effectiveness of resin-based fissure sealants (FS) and fluoride varnish (FV) in children at high caries risk. A practice-based split-mouth randomized clinical trial was conducted at 9 Public Dental Service (PDS) clinics in Norway. In total, 409 children age 6 to 10 y at high caries risk (d3mft > 0) meeting inclusion criteria were recruited by dentists and dental hygienists during routine examination. Eligibility criteria were 2 fully erupted first permanent molars (FPMs) in the same jaw, with sound occlusal surfaces or with initial caries. Participation was voluntary, caregivers and eligible children were informed about the study, and written parental consent was obtained. FS and FV were randomly applied on contralateral FPMs in the same jaw, with each participant serving as their own control. FS was applied at baseline and thereafter maintained according to clinicians' conventional procedures, whereas FV was applied at baseline, 6 mo, and 12 mo. The study outcome was success, with no need for invasive treatment (caries control), while failure was defined as dentin carious lesion or restoration. Two-level mixed-effects logistic regression analysis was used to compare FS and FV groups. Of 409 recruited children, 369 (90%) children/tooth pairs were examined after 36 mo. Intention-to-treat analysis showed 94.1% adjusted predicted probability (aPP) of success (95% confidence interval [CI] 91.7 to 96.4) in the FS group and 89.6% aPP (95% CI 86.5 to 92.7) in the FV group. In the adjusted analysis, the FV group had a lower OR for success compared with the FS group (OR 0.54, 95% CI 0.24 to 0.87). In the population studied, the clinical effectiveness of FS was statistically significantly higher compared with FV but below the estimated minimal clinically important difference of 10%.

Short-Wavelength Infrared Imaging of Infected and Affected Dentin

Stains produced by bacteria or those found in blood and food byproducts accumulate in highly porous caries lesions. They can interfere with accurate diagnosis and the selective removal of carious tissue during cavity preparations. Short-wavelength infrared (SWIR) imaging studies have shown that stain molecules do not absorb light beyond 1200 nm. The objective of this study was to image affected and infected dentin atSWIR wavelengths. Sections of 3 mm thickness were cut from the extracted teeth with deep dentinal lesions. The sound (normal), affected (stained), and infected (demineralized) dentin on each section were examined with reflected light at wavelengths from 400 to 1700 nm, red and green fluorescence, and with optical coherence tomography (OCT). Microcomputed tomography (microCT) was used to measure the mineral density at each location investigated. Significant (p < 0.05) differences were observed in the reflected light intensity at 400-850 nm and for fluorescence between the sound, affected, and infected dentin. SWIR imaging did not show significant reductions in reflectivity for the affected and infected dentin. SWIR images may be valuable for monitoring the lateral spread of dentinal lesions on the occlusal surfaces of teeth.

Diagnostic Performance of Multispectral SWIR Transillumination and Reflectance Imaging for Caries Detection

The aim of this clinical study was to compare the diagnostic performance of dual short wavelength infrared (SWIR) occlusal transillumination and reflectance multispectral imaging with conventional visual assessment and radiography for caries detection on premolars scheduled for extraction for orthodontics reasons. Polarized light microscopy (PLM) and micro-computed tomography (microCT) performed after tooth extraction were used as gold standards. The custom-fabricated imaging probe was 3D-printed and the imaging system employed a SWIR camera and fiber-optic light sources emitting light at 1300 nm for occlusal transillumination and 1600 nm for reflectance measurements. Teeth (n = 135) on 40 test subjects were imaged in vivo using the SWIR imaging prototype in the study and teeth were extracted after imaging. Our study demonstrates for the first time that near-simultaneous real-time transillumination and reflectance video can be successfully acquired for caries detection. Both SWIR imaging modalities had markedly higher sensitivity for lesions on proximal and occlusal surfaces compared to conventional methods (visual and radiographic). Reflectance imaging at 1600 nm had higher sensitivity and specificity than transillumination at 1300 nm. The combined SWIR methods yielded higher specificity but the combined sensitivity was lower than for each individual method.

Early occlusal caries detection using targeted fluorescent starch nanoparticles

OBJECTIVES

We have previously shown fluorescent cationic starch nanoparticles (FCSNs) penetrate enamel surface porosity of active carious lesions, potentially aiding their detection. Here, we evaluate the in vitro diagnostic accuracy of FCSNs in detecting occlusal caries compared to histologic reference standard.

METHODS

100 extracted human teeth were selected with sound (50), or either non-cavitated (25) or cavitated (25) lesions. A region of interest (ROI) on the occlusal surface was assessed for fluorescence by two independent examiners, after immersion in FCSN solution, water rinse, and illumination by dental curing lamp viewed through orange UV-filter glasses. ROIs were sectioned and evaluated by histology (Downer Criteria) as a gold standard for caries presence. Cohen's Kappa was determined for inter- and intra-examiner agreement, and sensitivity, specificity, and area under the curve of Receiver Operator Curves (ROC_AUC) were calculated. The analysis was repeated for the subset of "early" lesions, defined as being limited to enamel.

RESULTS

FCSN use resulted in substantial inter-user (k=0.74±0.07), and high intra-user agreement (k=0.80±0.06; 0.94±0.03, by examiner). Sensitivity, specificity and ROC_AUC for FCSNs were 88.9%; 94.6%; 0.92±0.06 for all, and 76.9%, 94.6%, and 0.86±0.10 for early lesions. In post hoc analysis, sensitivity seemed to be greater with the FCSN than the expert visual exam, particularly for early lesions.

CONCLUSIONS/CLINICAL SIGNIFICANCE

FCSNs are a reproducible and accurate novel technology for occlusal caries detection, with high sensitivity and specificity compared to histology. Future clinical validation is necessary. FCSNs can improve early caries detection and shift treatment towards non-invasive approaches, improving oral health.

Dual short wavelength infrared transillumination/reflectance mode imaging for caries detection

SIGNIFICANCE

We have developed a clinical probe capable of acquiring near-simultaneous short-wavelength infrared (SWIR) reflectance and occlusal transillumination images of lesions on tooth proximal and occlusal surfaces. We hypothesize that dual images will aid in differentiating between shallow and deep occlusal lesions and reduce the potential of false positives (FPs).

AIM

The aim of this study was to test the performance of the dual reflectance and occlusal transillumination probe on extracted teeth prior to commencing clinical studies.

APPROACH

The dual probe was 3D printed and the imaging system uses an InGaAs camera and broadband superluminescent diode light sources that emit broadband light at 1300 nm for occlusal transillumination and 1600-nm light for cross-polarization reflectance. The diagnostic performance of the dual probe was assessed using 120 extracted teeth with approximal and occlusal lesions. Reflectance and transillumination images were fused into single images to enhance the contrast between sound and lesion areas. The lesion contrast in both modes did not increase significantly with either the lesion depth or the distance from the occlusal surface for approximal lesions. In addition, the diagnostic performance of radiography, the individual reflectance and transillumination images, dual images, and fused images were compared using micro-computed tomography as the gold standard.

RESULTS

Reflectance imaging at 1600 nm yielded the highest diagnostic accuracy for lesions on both occlusal and proximal surfaces while radiography yielded the lowest number of FPs.

CONCLUSION

This study demonstrates that simultaneous acquisition of both reflectance and transillumination SWIR images is possible with a single clinical device.

Efficacy of P11-4 for the treatment of initial buccal caries: a randomized clinical trial

To investigate the safety and efficacy of Self-Assembling Peptide P₁₁-4 (SAP P₁₁-4) compared to placebo or fluoride varnish (FV), a randomized, controlled, blinded, split-mouth study with sequential design was conducted. Subjects presenting two teeth with White-Spot-Lesions (WSLs) were included and teeth were randomly assigned to test or control. Control received placebo at baseline (D0) and test SAP P₁₁-4, all received FV at Day 90 (D90). Standardized photographs were taken at each visit, and WSL size changes were morphometrically assessed. Hierarchical Linear Modelling, considering paired and sequential design, was used to test four hypotheses. SAP P₁₁-4 lesions (test, D90–D0) showed significant WSL size reduction compared to placebo (control, D90–D0; p = 0.008) or FV (control, D180–D90; p = 0.001). Combination of SAP P₁₁-4 and delayed FV after 90 days (test, D180–D0), showed a significant difference compared to FV alone (control D270–D90; p = 0.003). No significant difference on FV efficacy was found when SAP P₁₁-4 was applied 3 months before FV (test D270–D90; control D270–D90, p = 0.70). SAP P₁₁-4 treatment resulted in superior caries regression compared to either placebo or FV, and FV efficacy seems not to be affected by SAP P₁₁-4. SAP P₁₁-4 was found to be a safe and effective WSL treatment.

A dual handheld SWIR transillumination/reflectance probe for imaging lesions on tooth occlusal and proximal surfaces

We developed a clinical probe capable of acquiring simultaneous short wavelength infrared (SWIR) reflectance and occlusal transillumination images of lesions on tooth proximal and occlusal surfaces to reduce the potential of false positives. The dual probe is 3D-printed and the imaging system uses a Ge-enhanced camera and fiber-optic light sources that use SWIR light at 1300-nm for occlusal transillumination and SWIR 1450-nm light for reflectance measurements. The purpose of this study was to test the performance of the probe on extracted teeth prior to commencing clinical studies. The dual probe was used to image extracted teeth with proximal and occlusal lesions. SWIR images of each tooth were compared with micro-CT images to assess performance.

In Vitro Microleakage Comparison of Flowable Nanocomposites and Conventional Materials Used in Pit and Fissure Sealant Therapy

Objectives:

Pit and fissure sealants are recognized as an effective preventive approach in pediatric dentistry. Composite resin is the most commonly used sealant material. Adding nanoparticles to composite resin could result in production of flowable composite with higher mechanical properties and better flowability than previous sealants. This study aimed to compare the microleakage of a flowable nanocomposite and materials conventionally used as pit and fissure sealants.

Materials and Methods:

A total of 185 extracted mandibular third molar teeth were selected and randomly divided into 5 groups (n=36): flowable nanocomposite, flowable composite, filled sealants, nano-filled sealants, and unfilled sealants. Five teeth were reserved for examination under a scanning electron microscope (SEM). The samples were thermocycled (5–55°C, 1-minute dwell time) for 1000 cycles and immersed in 0.2% fuchsine solution for 24 hours. Teeth were sectioned buccolingually. Microleakage was assessed qualitatively and quantitatively by means of dye penetration and SEM. Data were analyzed using chi-square, Kruskal-Wallis, and Bonferroni-corrected Mann-Whitney U tests.

Results: Qualitative microleakage assessment showed that flowable composite and nanofilled flowable composite had almost no microleakage (P<0.001). Regarding quantitative scores, the nanofilled flowable composite and unfilled fissure sealant showed the lowest and the highest rate of microleakage, respectively. No statistically significant difference was found between the two flowable composites (P=0.317). Filled resin-based sealant had significantly lower microleakage than unfilled resin-based sealant (P<0.001).

Conclusion:

Use of flowable and nanofilled flowable composites (but not unfilled resin-based fissure sealant) is recommended for sealing of pits and fissures of molars.

Multispectral near-infrared reflectance and transillumination imaging of occlusal carious lesions: Variation in lesion contrast with lesion depth

In vivo and in vitro studies have demonstrated that near-infrared (NIR) light at λ=1300-1700-nm can be used to acquire high contrast images of enamel demineralization without interference of stains. The objective of this study was to determine if a relationship exists between the NIR image contrast of occlusal lesions and the depth of the lesion. Extracted teeth with varying amounts of natural occlusal decay were measured using a multispectral-multimodal NIR imaging system which captures λ=1300-nm occlusal transillumination, and λ=1500-1700-nm cross-polarized reflectance images. Image analysis software was used to calculate the lesion contrast detected in both images from matched positions of each imaging modality. Samples were serially sectioned across the lesion with a precision saw, and polarized light microscopy was used to measure the respective lesion depth relative to the dentinoenamel junction. Lesion contrast measured from NIR cross-polarized reflectance images positively correlated (p<0.05) with increasing lesion depth and a statistically significant difference between inner enamel and dentin lesions was observed. The lateral width of pit and fissures lesions measured in both NIR cross-polarized reflectance and NIR transillumination positively correlated with lesion depth.

Dentists' decision strategies for suspicious occlusal caries lesions in a National Dental PBRN study

OBJECTIVE

Case presentations (vignettes) were completed by dentists in the National Dental Practice-Based Research Network study "Decision Aids for the Management of Suspicious Occlusal Caries Lesions (SOCLs)". The objective was to determine dentists' decision strategies for SOCLs.

METHODS

107 dentists viewed a series of 16 vignettes that represented all combinations of 4 clinical cues: color, luster, lesion roughness, and patient-level caries risk. Each vignette included a patient description and a photograph of a tooth presenting the 4 cues. Dentists were asked to decide the likelihood that a suspected lesion extended into dentin. A lens model analysis was used to examine how dentists use these cues in making their decisions.

RESULTS

86% of dentists had a consistent pattern of cue use that defined their decision strategy. On average, 70% of the variance in their decisions was accounted for by their use of the 4 cues. However, there was considerable variability in the individual cues used by each dentist. The percentages of dentists who used the different cues consistently were: luster (58%), color (48%), roughness (36%), and risk (35%). 14% of dentists reliably used only color, 7% used only luster, 4% used only roughness, and 1% used only risk when making SOCL decisions.

CONCLUSIONS

The online vignette system suggests that clinical SOCL decision strategies are highly individualized and dentists do not use all cues available to them to make these decisions.

CLINICAL SIGNIFICANCE

Prior to this study, there has been little evidence about how dentists use these cues (either individually or in combination) when judging the extent of caries progression. Such knowledge would be valuable when designing interventions to help dentists maximize the likelihood of appropriate treatment decisions.

Surface characteristics and lesion depth and activity of suspicious occlusal carious lesions: Findings from The National Dental Practice-Based Research Network

BACKGROUND

A lesion on an occlusal tooth surface with no cavitation and no radiographic radiolucency but in which caries is suspected owing to surface roughness, opacities, or staining can be defined as a suspicious occlusal carious lesion (SOCL). The authors' objective was to quantify the characteristics of SOCLs and their relationship to lesion depth and activity after these lesions were opened surgically.

METHODS

Ninety-three dentists participated in the study. When a consenting patient had an SOCL, information was recorded about the tooth, lesion, treatment provided, and, if the SOCL was opened surgically, its lesion depth. The Rao-Scott cluster-adjusted χ² test was used to evaluate associations between lesion depth and color, roughness, patient risk, and luster.

RESULTS

The authors analyzed 1,593 SOCLs. Lesion color varied from yellow/light brown (40%) to dark brown/black (47%), with 13% other colors. Most (69%) of SOCLs had a rough surface when examined with an explorer. Over one-third of the SOCLs (39%) were treated surgically. Of the 585 surgically treated SOCLs, 61% had dentinal caries. There were statistically significant associations between lesion depth and color (P = .03), luster (P = .04), and roughness (P = .01). The authors classified 52% of the patients as being at elevated caries risk. The authors found no significant associations between lesion depth and patient risk (P = .07).

CONCLUSIONS

Although statistically significant, the clinical characteristics studied do not provide accurate guidance for making definitive treatment decisions and result in high rates of false positives.

PRACTICAL IMPLICATIONS

Given that 39% of the opened lesions did not have dentinal caries or were inactive, evidence-based preventive management is an appropriate alternative to surgical intervention.

Restorative treatment for initial, cavitated and gross coronal carious lesions

BACKGROUND

Treatment patterns for caries have been shown to reflect high rates of restorative services. The objective of this study was to investigate types of restorative treatment provided to patients with a main diagnosis of coronal caries in relation to the severity of the caries lesion.

METHODS

A random sample of Australian dentists was surveyed by mailed questionnaires in 2009-2010 (response rate 67%). Data on types of restorative treatment, patient characteristics and main diagnosis were collected from a service log.

RESULTS

Models of service rates adjusted for age, gender, insurance status and reason for visit showed that compared to the reference category of initial caries lesions, there were lower rates [Rate Ratio, 95% CI] of adhesive anterior restorative services [0.57, 0.34-0.95] and lower rates of adhesive posterior restorations [0.56, 0.40-0.79] for gross lesions.

CONCLUSIONS

Treatment of coronal caries was characterized by high rates of adhesive posterior restorative services, but gross lesions had lower rates of both anterior and posterior adhesive restorations. Types of restorative treatment for coronal caries were similar between initial and cavitated lesions. This could indicate scope for the adoption of more minimum intervention approaches to the management of initial carious lesions.

Near-IR and CP-OCT imaging of suspected occlusal caries lesions

INTRODUCTION

Radiographic methods have poor sensitivity for occlusal lesions and by the time the lesions are radiolucent they have typically progressed deep into the dentin. New more sensitive imaging methods are needed to detect occlusal lesions. In this study, cross-polarization optical coherence tomography (CP-OCT) and near-IR imaging were used to image questionable occlusal lesions (QOC's) that were not visible on radiographs but had been scheduled for restoration on 30 test subjects.

METHODS

Near-IR reflectance and transillumination probes incorporating a high definition InGaAs camera and near-IR broadband light sources were used to acquire images of the lesions before restoration. The reflectance probe utilized cross-polarization and operated at wavelengths from 1,500 to 1,700 nm where there is an increase in water absorption for higher contrast. The transillumination probe was operated at 1,300 nm where the transparency of enamel is highest. Tomographic images (6 × 6 × 7 mm³ ) of the lesions were acquired using a high-speed swept-source CP-OCT system operating at 1,300 nm before and after removal of the suspected lesion.

RESULTS

Near-IR reflectance imaging at 1,500-1,700 nm yielded significantly higher contrast (P < 0.05) of the demineralization in the occlusal grooves compared with visible reflectance imaging. Stains in the occlusal grooves greatly reduced the lesion contrast in the visible range yielding negative values. Only half of the 26 lesions analyzed showed the characteristic surface demineralization and increased reflectivity below the dentinal-enamel junction (DEJ) in 3D OCT images indicative of penetration of the lesion into the dentin.

CONCLUSION

This study demonstrates that near-IR imaging methods have great potential for improving the early diagnosis of occlusal lesions. Lasers Surg. Med. 49:215-224, 2017. © 2017 Wiley Periodicals, Inc.

A system for simultaneous near-infrared reflectance and transillumination imaging of occlusal carious lesions

Clinicians need technologies to improve the diagnosis of questionable occlusal carious lesions (QOC's) and determine if decay has penetrated to the underlying dentin. Assessing lesion depth from near-infrared (NIR) images holds great potential due to the high transparency of enamel and stain to NIR light at λ=1300-1700-nm, which allows direct visualization and quantified measurements of enamel demineralization. Unfortunately, NIR reflectance measurements alone are limited in utility for approximating occlusal lesion depth >200-μm due to light attenuation from the lesion body. Previous studies sought to combine NIR reflectance and transillumination measurements taken at λ=1300-nm in order to estimate QOC depth and severity. The objective of this study was to quantify the change in lesion contrast and size measured from multispectral NIR reflectance and transillumination images of natural occlusal carious lesions with increasing lesion depth and severity in order to determine the optimal multimodal wavelength combinations for estimating QOC depth. Extracted teeth with varying amounts of natural occlusal decay were measured using a multispectral-multimodal NIR imaging system at prominent wavelengths within the λ=1300-1700-nm spectral region. Image analysis software was used to calculate lesion contrast and area values between sound and carious enamel regions.

Twenty-month follow-up of occlusal caries lesions deemed questionable at baseline: findings from the National Dental Practice-Based Research Network

BACKGROUND

A questionable occlusal caries (QOC) lesion can be defined as an occlusal surface with no radiographic evidence of caries, but caries is suspected because of clinical appearance. In this study, the authors report the results of a 20-month follow-up of these lesions.

METHODS

Fifty-three clinicians from The National Dental Practice-Based Research Network participated in this study, recording lesion characteristics at baseline and lesion status at 20 months.

RESULTS

At baseline, 1,341 QOC lesions were examined; the treatment that was planned for 1,033 of those at baseline was monitoring (oral hygiene instruction, applying or prescribing fluoride or varnish, or both), and the remaining 308 received a sealant (n = 192) or invasive therapy (n = 116). At the 20-month visit, clinicians continued to monitor 927 (90 percent) of the 1,033 monitored lesions. Clinicians decided to seal 61 (6 percent) of the 1,033 lesions (mean follow-up, 19 months) and invasively treat 45 (4 percent) of them (mean follow-up, 15 months). Young patient age (< 18 years) (odds ratio = 3.4; 95 percent confidence interval, 1.7-6.8) and the lesion's being on a molar (odds ratio = 1.8; 95 percent confidence interval, 1.3-2.6) were associated with the clinician's deciding at some point after follow-up to seal the lesion or treat it invasively.

CONCLUSIONS

Almost all (90 percent) QOC lesions for which the treatment planned at baseline was monitoring still were planned to undergo monitoring after 20 months. This finding suggests that noninvasive management is appropriate for these lesions.

PRACTICAL IMPLICATIONS

Previous study results from baseline indicated a high prevalence of QOC lesions (34 percent). Clinicians should consider long-term monitoring when making treatment decisions about these lesions.

The Effect of Combining Radiographs and DIAGNOdent With Visual Examination on Detection and Treatment Decisions of Noncavitated Occluso-dentinal Caries

The aim of this laboratory study was to evaluate the effectiveness of incorporating radiographic examination and DIAGNOdent with visual examination for the detection and treatment of noncavitated occluso-dentinal caries. Four examiners examined the occlusal surfaces of 160 extracted posterior teeth. Teeth were examined three times with a one-month interval in between. The first examination was visual (V), the second examination was visual with radiograph (VR), and the third examination was visual with radiograph and DIAGNOdent (VRD). Examiners were asked to detect the presence of caries (if any) and identify the extent of caries (if present; ie, enamel or dentin). The examiners were also asked to choose a treatment for each tooth. The examined teeth were later sectioned, and the presence of caries was charted as 0 = no caries, 1 = caries confined to enamel, 2 = caries in the outer dentin, and 3 = caries in the inner dentin. Sensitivity, specificity, area under the curve (Az values), rank correlation coefficient, interexaminer reproducibility, and McNemar χ(2) tests were calculated. VR had statistically higher specificity and lower sensitivity than V and VRD. The means of Az values ranged from 0.58 to 0.63, with no statistical difference between the three examinations (p>0.05). The means of the rank correlation coefficients with histology for detection of dentinal caries were 0.48, 0.23, and 0.44 using V, VR, and VRD, respectively. Interexaminer reproducibility was best for V alone. The percentages of teeth indicated for restorative treatment were 31%, 33%, and 41% using V, VR, and VRD, respectively. The percentages of teeth correctly treated according to histology were 69.4%, 70.0%, and 67.5% using V, VR, and VRD, respectively. There was no difference in the accuracy of treatment decisions between the three examination points (p>0.05). The addition of radiographs and DIAGNOdent to visual examination did not have a significant effect on the improvement of the detection or treatment decisions of examiners of noncavitated occluso-dentinal carious lesions.

The minimally invasive management of early occlusal caries: a practical guide

Pits and fissures on the occlusal surfaces of posterior teeth are sites affected commonly by demineralisation caused by the caries process. Clinicians face daily challenges in detecting these lesions, accurately diagnosing their activity and choosing from a range of management options. Traditionally, the detection of an active (or potentially active) occlusal lesion invariably resulted in the preparation of a standardised occlusal cavity, often extending beyond the confines of diseased tissue, followed by the insertion of a direct restorative material, most commonly dental amalgam. The overwhelming weight of contemporary evidence now favours minimally invasive (MI) operative management when required (usually after non-operative prevention has failed), and a wide range of equipment, materials and operative techniques is available to help operators to preserve the maximum amount of healthy/repairable tooth tissue and to allow restoration with more biologically respectful, tooth-preserving materials. This paper aims to provide clinicians with practical guidance in the prevention, early detection, predictable diagnosis and minimally invasive management of early occlusal carious lesions.

Characteristics, detection methods and treatment of questionable occlusal carious lesions: findings from the national dental practice-based research network

Questionable occlusal carious lesions (QOC) can be defined as an occlusal tooth surface with no cavitation and no radiographic radiolucencies, but caries is suspected due to roughness, surface opacities or staining. An earlier analysis of data from this study indicates 1/3 of patients have a QOC. The objective of this report has been to quantify the characteristics of these common lesions, the diagnostic aids used and the treatment of QOC. A total of 82 dentist and hygienist practitioner-investigators from the USA and Denmark in the National Dental Practice-Based Research Network participated. When consenting patients presented with a QOC, information was recorded about the patient, tooth, lesion and treatments. A total of 2,603 QOC from 1,732 patients were analyzed. The lesions were usually associated with a fissure, on molars, and varied from yellow to black in color. Half presented with a chalky luster and had a rough surface when examined with an explorer. There was an association between color and luster: 10% were chalky-light, 47% were shiny-dark and 42% were mixtures. A higher proportion of chalky than of shiny lesions were light (22 vs. 9%; p < 0.001). Lesions light in color were less common in adults than in pediatric patients (9 vs. 32%; p < 0.001). Lesions that were chalky and light were more common among pediatric than among adult patients (22 vs. 6%; p < 0.001). This is the first study to investigate characteristics of QOC in routine clinical practice. Clinicians commonly face this diagnostic uncertainty. Determining the characteristics of these lesions is relevant when making diagnostic and treatment decisions.