Effect of different diagnostic thresholds on dental caries calibration - a 12 month evaluation

OBJECTIVE: To analyze the reproducibility of a calibration trial, at different diagnostic thresholds of dental caries, in a 12-month evaluation. METHODS: A group of dental examiners (n = 11), who had previous experience in epidemiological surveys, participated in the study. An initial training phase (theoretical and clinical) and five calibration exercises (baseline, 3, 6, 9 and 12 months) were arranged. World Health Organization (WHO) criteria, including the active initial lesions (IL) were used. Six- to 7-year-old children took part in the study. They were selected according to past history and dental caries activity. The data were analyzed at WHO and WHO + IL diagnostic thresholds in accordance with tooth and dental surfaces. RESULTS: Excellent mean intra- and inter-examiner Kappa values were obtained for both diagnostic thresholds, in accordance with tooth and surface, during the calibration phases. However, the most relevant errors were related to the decayed component and to IL diagnosis. CONCLUSION: It was possible to use the methodology proposed in this study in epidemiological surveys when examining the mixed dentition, although new strategies to improve training in IL diagnosis and calibration are necessary.     

A NEW APPROACH FOR INTEREXAMINER RELIABILITY DATA ANALYSIS ON DENTAL CARIES CALIBRATION

Objectives

a) to evaluate the interexaminer reliability in caries detection considering different diagnostic thresholds and b) to indicate, by using Kappa statistics, the best way of measuring interexaminer agreement during the calibration process in dental caries surveys.

Methods

Eleven dentists participated in the initial training, which was divided into theoretical discussions and practical activities, and calibration exercises, performed at baseline, 3 and 6 months after the initial training. For the examinations of 6-7-year-old schoolchildren, the World Health Organization (WHO) recommendations were followed and different diagnostic thresholds were used: WHO (decayed/missing/filled teeth – DMFT index) and WHO + IL (initial lesion) diagnostic thresholds. The interexaminer reliability was calculated by Kappa statistics, according to WHO and WHO+IL thresholds considering: a) the entire dentition; b) upper/lower jaws; c) sextants; d) each tooth individually.

Results

Interexaminer reliability was high for both diagnostic thresholds; nevertheless, it decreased in all calibration sections when considering teeth individually.

Conclusion

The interexaminer reliability was possible during the period of 6 months, under both caries diagnosis thresholds. However, great disagreement was observed for posterior teeth, especially using the WHO+IL criteria. Analysis considering dental elements individually was the best way of detecting interexaminer disagreement during the calibration sections.     

Effect of diagnostic threshold on the validity and reliability of epidemiological caries diagnosis using the Dundee Selectable Threshold Method for caries diagnosis (DSTM)

OBJECTIVES: To develop a method for recording dental caries at the D1 (enamel and dentine) diagnostic threshold (without loss of D3 information) and assess its reliability, 'benchmark' validity and potential effects on reported caries prevalence and needs assessment. METHODS: Multi-examiner training, calibration and validation trial. Two groups of 10 dental examiners were trained to diagnose dental caries at the D1 (enamel and dentine) diagnostic threshold under the conditions of a caries prevalence survey, prior to a calibration trial being undertaken. RESULTS: Where 'experienced examiners' were trained to examine at the D1 (enamel and dentine) diagnostic threshold, under the conditions of a cross-sectional epidemiological survey, there was no significant deterioration in inter-examiner agreement on the assessment of teeth and a significant difference in one of two comparisons on the assessment of surfaces using the kappa statistic. Assessed against a benchmark examiner, there was no significant loss of sensitivity at the D1 diagnostic threshold compared with the D3 threshold and, although there was a significant loss of specificity at the D1 threshold, all specificity values could be considered to be high. CONCLUSIONS: Modifying the diagnostic criteria typically used in surveys of caries prevalence (to allow assessment of the levels of enamel caries which could benefit from preventive care as well as dentinal caries requiring restorative care) in adolescents does not adversely affect the reliability or benchmark validity of experienced examiners to a significant degree.     

In vitro validity of the Dundee Selectable Threshold Method for caries diagnosis (DSTM)

OBJECTIVES: It is not generally possible to assess diagnostic accuracy in dental surveys as no histological 'gold standards' are available, therefore examiner agreement tends to be used as a proxy for accuracy. The aim of this study was to investigate, using extracted teeth in arch models, the in vitro validity of a diagnostic system to assess caries at the D1 (enamel and dentine) and D3 (dentine) diagnostic thresholds, for epidemiological purposes. METHOD: Two groups of 10 dental examiners trained in the use of the Dundee Selectable Threshold Method for caries diagnosis (DSTM) each examined (on two occasions) 160 extracted permanent molar and premolar teeth set in arch models in phantom heads according to the codes and criteria of the DSTM. The teeth were subsequently radiographed and sectioned to provide validation of the diagnoses. RESULTS: Intra-examiner agreement according to the kappa statistic was substantial. In general terms the results of the in vitro validation exercise demonstrated significantly higher sensitivity values at the D1 diagnostic threshold than were found at the D3 diagnostic threshold with a consequent loss of specificity. CONCLUSIONS: The results of this in vitro validation exercise demonstrate that at the D1 diagnostic threshold the sensitivity of the DSTM was greater than at the D3 threshold indicating no loss of diagnostic accuracy at the D1 threshold.     

The effect of varying diagnostic thresholds upon clinical caries data for a low prevalence group

This study investigated the impact of employing differing diagnostic thresholds on clinical caries data in studies of groups with low caries prevalence. Data from clinical examinations of 287 Hong Kong dental students were analyzed by means of the CARIES microcomputer software package. This software allows for re-calculation of raw data according to three different diagnostic thresholds (D3, D2, and D1). When "enamel" and "initial" lesions (as defined by WHO criteria) were included in the calculation of DMFT, its value increased from 3.0 (D3) to 5.9 (D1), while the percentage of individuals considered "caries-free" decreased from 28.2% to 7.0%. Little change was found in the magnitude of the intra-examiner reproducibility, when calculated at each threshold, for a random 10% of the subjects. It was unfortunately not possible to calculate inter-examiner reproducibility in this study. The use of criteria which might be misinterpreted as being similar, but which use differing effective diagnostic thresholds, can dramatically influence the reported level of dental caries. In view of these findings, it may be necessary for the question of diagnostic thresholds to be re-examined and to receive greater emphasis in future studies.     

Assessment of different methods for diagnosing dental caries in epidemiological surveys

AIMS: The aims of the study were: (i) to assess different clinical diagnostic methods of dental caries during epidemiological surveys; (ii) to determine which combinations of methods and diagnostic adjuncts show the best performances in epidemiological surveys when compared with examinations performed in a traditional dental setting (standard); (iii) to evaluate the influence of including noncavitated (NC) lesions in dental caries estimation. METHODS: Forty 12-year-old children were divided into low and moderate caries prevalence groups. The individuals were submitted to 12 epidemiological examinations (in an outdoor setting), which combined three methods (blade, mirror and mirror + CPI (Community Periodontal Index) dental probe) with or without diagnostic adjuncts (previous dental brushing and dental drying). The last examination was performed in a traditional dental setting (standard examination). The unit of measure was the DMFS (decayed, missing and filled surfaces) index according to WHO criteria. The variance analysis, Dunnet's and Tukey's tests were applied. RESULTS: For the DMFS analysis, the visual/tactile method, with or without diagnostic adjuncts, was the best method for both groups, presenting a performance higher than 90% when compared with the standard examination, except for the examinations without previous dental brushing for the low caries prevalence group. Previous dental brushing was more relevant than dental drying (P = 0.0054). All of the epidemiological examinations underestimated the NC diagnosis even with the association of diagnostic adjuncts when compared with the standard examination. CONCLUSION: The visual-tactile (for both groups) and the visual (mirror) methods plus dental brushing (for the moderate group) are appropriate for diagnosing cavitated lesions, but not NC lesions.     

Examiner training and reliability in two randomized clinical trials of adult dental caries

Objectives: This report describes the training of dental examiners participating in two dental caries clinical trials and reports the inter‐ and intra‐examiner reliability scores from the initial standardization sessions. Methods: Study examiners were trained to use a modified International Caries Detection and Assessment System II system to detect the visual signs of non‐cavitated and cavitated dental caries in adult subjects. Dental caries was classified as no caries (S), non‐cavitated caries (D1), enamel caries (D2), and dentine caries (D3). Three standardization sessions involving 60 subjects and 3,604 tooth surface calls were used to calculate several measures of examiner reliability. Results: The prevalence of dental caries observed in the standardization sessions ranged from 1.4 percent to 13.5 percent of the coronal tooth surfaces examined. Overall agreement between pairs of examiners ranged from 0.88 to 0.99. An intra‐class coefficient threshold of 0.60 was surpassed for all but one examiner. Inter‐examiner unweighted kappa values were low (0.23‐0.35), but weighted kappas and the ratio of observed to maximum kappas were more encouraging (0.42‐0.83). The highest kappa values occurred for the S/D1 versus D2/D3 two‐level classification of dental caries, for which seven of the eight examiners achieved observed to maximum kappa values over 0.90. Intra‐examiner reliability was notably higher than inter‐examiner reliability for all measures and dental caries classifications employed. Conclusion: The methods and results for the initial examiner training and standardization sessions for two large clinical trials are reported. Recommendations for others planning examiner training and standardization sessions are offered.     

Laser fluorescence device does not perform well in detection of early caries lesions in primary teeth: an in vitro study

PURPOSE: To evaluate if using the laser fluorescence (LF) device improves the detection of early or more advanced occlusal caries lesions in primary teeth. MATERIALS AND METHODS: A total of 181 occlusal sites in primary teeth were assessed by one examiner using DIAGNOdent. The same examiner and a second examiner evaluated 72 of the sites again to assess intra- and inter-examiner reproducibility. After histological validation, lesions were divided at three thresholds according to the lesion depth: outer half of the enamel (D1), inner half of the enamel (D2) and dentine (D3). The sensitivity, specificity, accuracy and area under ROC curve were calculated for cut-off points for the sample considering the aforementioned thresholds. The parameters were compared using chi-square test and by comparison between unpaired ROC curves. RESULTS: The overall LF performance was better at dentine threshold than at enamel threshold. The higher specificity was found at D3 and D2, and higher accuracy at D3 (P < 0.001). The intra- and inter-examiner agreements were classified as good or excellent for all thresholds. CONCLUSIONS: The LF device performs better at the dentine threshold than at the enamel threshold. This method does not perform well in detecting initial enamel caries lesions.     

Influence of diagnostic adjuncts to the measurement of caries prevalence at different caries thresholds

OBJECTIVES: To determine the influence of diagnostic adjuncts (dental brushing and drying) in dental caries diagnosis. To analyse the underestimation levels in epidemiological examinations when compared to traditional dental setting examinations. To evaluate the influence of including noncavitated (NC) carious lesions in the estimation of the disease. PARTICIPANTS: 51, 12-year-old children. INTERVENTIONS/METHODS: Four epidemiological exams performed in an outdoor setting and one performed in a traditional dental setting (visual-tactile method associated or not with diagnostic adjuncts). MAIN OUTCOME MEASURES: DMFS (Decayed, Missing and Filled Surfaces) index, according to the WHO criteria. RESULTS: When compared to exams carried out in a traditional dental setting, the epidemiological examinations showed no significant statistical differences for the DMFS score (p>0.05), presenting underestimation levels lower than 10% (except for the low prevalence caries group in the WHO exam). For the DMFS, previous dental brushing was more relevant than previous dental drying, although drying was the most important resource for NC diagnosis (p<0.05). CONCLUSION: The visual/tactile method, with or without diagnostic adjuncts, can diagnose cavitated lesions efficiently, but not NC lesions. However, for the low caries prevalence group, the implementation of dental brushing prior to an exam could be suggested.     

Occlusal caries detection in primary teeth: a comparison of DIAGNOdent with conventional methods

OBJECTIVE: To compare the accuracy and repeatability of three diagnostic systems (DIAGNOdent, visual and radiographic) for occlusal caries diagnosis in primary molars. DESIGN: Two examiner, in vitro, blinded study. Histological gold standard. MATERIALS AND METHODS: 58 occlusal surfaces of primary molars examined in turn by two examiners using each of three diagnostic systems (DIAGNOdent, visual and radiographic). These results were compared with a histological gold standard. Sensitivity and specificity were calculated for each diagnostic system at a range of thresholds. Inter- and intra- examiner repeatability were calculated for each diagnostic system using the kappa statistic. MAIN OUTCOME MEASURES: Sensitivity, specificity, inter and intra examiner repeatability for each diagnostic system. RESULTS: The highest sensitivity values were provided by DIAGNOdent (0.77 and 0.80, examiners 1 and 2 respectively) however this was offset by a lower specificity (0.82 and 0.85) than all other systems with the exception of examiner 1 at V1 visual threshold. The DIAGNOdent gave the highest values of kappa for intra- and inter-examiner repeatability with the exception of intra-examiner repeatability for examiner 2 where visual diagnosis had the highest value of kappa. CONCLUSION: The DIAGNOdent was the most accurate system tested for the detection of occlusal dentine caries in primary molars. The performance of the DIAGNOdent systems was not statistically significantly better than that achieved using visual examination for non-cavitated teeth (V1 and V2 threshold). DIAGNOdent may prove useful as a predictive clinical tool, however with appropriate training visual examination may offer similar results without the need for additional equipment.     

Measurement, analysis and interpretation of examiner reliability in caries experience surveys: some methodological thoughts

Data obtained from calibration exercises are used to assess the level of agreement between examiners (and the benchmark examiner) and/or between repeated examinations by the same examiner in epidemiological surveys or large-scale clinical studies. Agreement can be measured using different techniques: kappa statistic, percentage agreement, dice coefficient, sensitivity and specificity. Each of these methods shows specific characteristics and has its own shortcomings. The aim of this contribution is to critically review techniques for the measurement and analysis of examiner agreement and to illustrate this using data from a recent survey in young children, the Smile for Life project. The above-mentioned agreement measures are influenced (in differing ways and extents) by the unit of analysis (subject, tooth, surface level) and the disease level in the validation sample. These effects are more pronounced for percentage agreement and kappa than for sensitivity and specificity. It is, therefore, important to include information on unit of analysis and disease level (in validation sample) when reporting agreement measures. Also, confidence intervals need to be included since they indicate the reliability of the estimate. When dependency among observations is present [as is the case in caries experience data sets with typical hierarchical structure (surface–tooth–subject)], this will influence the width of the confidence interval and should therefore not be ignored. In this situation, the use of multilevel modelling is necessary. This review clearly shows that there is a need for the development of guidelines for the measurement, interpretation and reporting of examiner reliability in caries experience surveys.     

Assessment of cavitated and active non-cavitated caries lesions in 3- to 4-year-old preschool children: a field study

International Journal of Paediatric Dentistry 2012; 22: 92–99 Background. The prevalence of early childhood caries (ECC) is high in developing countries; thus, sensitive methods for the early diagnosis of ECC are of prime importance to implement the appropriate preventive measures. Aim. To investigate the effects of the addition of early caries lesions (ECL) into WHO threshold caries detection methods on the prevalence of caries in primary teeth and the epidemiological profile of the studied population. Design. In total, 351 3‐ to 4‐year‐old preschoolers participated in this cross‐sectional study. Clinical exams were conducted by one calibrated examiner using WHO and WHO + ECL criteria. During the exams, a mirror, a ball‐ended probe, gauze, and an artificial light were used. The data were analysed by Wilcoxon and Mc‐Nemar’s tests (α = 0.05). Results. Good intra‐examiner Kappa values at tooth/surface levels were obtained for WHO and WHO + ECL criteria (0.93/0.87 and 0.75/0.78, respectively). The dmfs scores were significantly higher (P < 0.05) when WHO + ECL criteria were used. ECLs were the predominant caries lesions in the majority of teeth. Conclusions. The results strongly suggest that the WHO + ECL diagnosis method could be used to identify ECL in young children under field conditions, increasing the prevalence and classification of caries activity and providing valuable information for the early establishment of preventive measures.     

The use of clinical dental auxiliaries as examiners in caries prevalence surveys in the United Kingdom: a feasibility study

Objectives : This study investigated the use of clinical dental auxiliaries as examiners in caries prevalence surveys of 5- and 12-year-old children in the United Kingdom. Methods: A random sample of four therapists and four hygienists was drawn from 23 clinical dental auxiliaries employed in the Community Dental Service in Yorkshire, United Kingdom. Training and calibration were carried out according to national guidelines for caries prevalence surveys. Sixteen 5-year-old and sixteen 12-year-old children were examined in the calibration exercise. Agreement was assessed using 95% condence intervals of mean dmft/DMFT of the group, sensitivity and specicity values, and kappa statistics on dft/DFT. Results: For 5-year-old children, a good level of agreement with the standard examiner was achieved with sensitivity scores ranging from 0.84–0.98, specicity scores from 0.93–0.97, and kappa scores from 0.80–0.89. For 12-year-old children, sensitivity scores ranged from 0.56–0.95; specicity scores from 0.93–0.99; and kappa scores from 0.66–0.83. Four examiners failed to achieve the minimum scores on all measurements. Conclusion: It was concluded that clinical dental auxiliaries could be used as examiners in caries prevalence surveys of 5-year-old children. However, in order to attempt to meet the national standard for agreement in surveys of 12-year-old children, four of the eight examiners in the present study would require further training. Possible reasons for this difference are discussed.     

Predicting the experience of dentinal caries or restorative dental treatment in adolescents using D1 and D3 visual caries assessments

Standardised epidemiological caries assessments used in oral health surveys have been shown to be poor at predicting whether a tooth surface will be treated restoratively when a patient visits a dentist. However, it has been argued that oral health surveys may be more relevant in determining needs at the level of an individual or groups of individuals. The objective of this study was to determine the discriminatory power of visual caries assessments at two thresholds (D1 & D3) in adolescents of average age 12.1 years to predict experience of dentinal caries 3 years later or the experience of restorative treatment (not re-treatment) during the 3-year period. The data was derived from a prospective 3-year longitudinal study in which the dental care provided by 41 dentists for 403 adolescents was monitored. Dental caries experience was monitored by annual standardised assessments of caries undertaken by a single trained examiner. ROC analysis showed that caries assessed visually at the D1 threshold in 12-year-olds was a better predictor (P < 0.001) of experiencing some dentinal caries after 3 years (Az = 0.781) than was caries assessed visually at D3 threshold in 12-year-olds (Az = 0.670). Assessing caries visually at either the D1 or the D3 threshold had no discriminatory power for predicting whether an individual would experience some restorative treatment during the ensuing 3-year period (Az for D1 = 0.507; Az for D3 = 0.518).     

Caries experience in the primary dentition among French 6-year-olds between 1991 and 2000

BACKGROUND: There are few national caries preventive policies for children in France. Various surveys suggest that in the late 1980s, oral health of the 6-year olds in France was poorer than in those of other European countries. In Val de Marne (a Department just east of Paris) a public dental service was established in 1991. A programme to inform preschool staff about dental diseases was commenced and volunteers brought oral health information to parents and health professionals. Periodical monitoring of primary tooth caries of 6-year olds was planned. AIM: The aim of the study was to evaluate changes in primary tooth caries in 6-year olds over the 10 years of the programme. METHODS: Participating 6-year olds, randomly selected, were examined in schools by dentists. Clinical data were collected (WHO criteria). Sociodemographic data were collected through questionnaire. Statistical analysis involved comparison of mean values, variance analysis and chi-square test for categorical variables. RESULTS: The proportions of children with caries experience were, 38.9%, 30.6% and 22.2% in 1991, 1995 and 2000 respectively (P < 0.01). The dft index decreased from 1.74 to 1.39 and 1.05 respectively. About 75% of children with dental caries remained untreated. Children of non-European native parents or belonging to low socioeconomic families remained those most affected by dental caries in 2000. CONCLUSION: Dental caries in 6-year olds improved between 1991 and 2000 in Val de Marne but caries remained a socially inequitable disease. Most children did not have access to dental care. The situation requires changes to the dental care provision system.     

Dental caries in Mexican schoolchildren: A comparison of 1988-1989 and 1998-2001 surveys

Objectives: To compare two surveys across seven states for the prevalence of dental caries among Mexican schoolchildren. Study Design: Analysis of two cross-sectional surveys: Schoolchildren from 6 to 10 years of age were examined in the 1988-1989 survey and 6- to 10-year-old and 12-year-old students were included in the 1998-2001 survey. The baseline data of seven states were available for analysis. Representative probability samples were conducted statewide in both surveys. The World Health Organization (WHO) method was used to obtain the dental caries index (dmft, DMFT). At present, additional and more recent epidemiological data representative statewide in Mexico are unavailable. Results: The participants were 9798 schoolchildren in the 1988-1989 survey and 16882 schoolchildren in the 1998-2001 survey. The prevalence of caries in children ages 6 to 10 years was 86,6% in the first survey and 65,5% in the second survey, showing a 24,4% reduction. The primary teeth index in the first survey was dmft = 3,86 (IC95% 3,68 4,04) and in permanent teeth, it was DMFT = 1,03 (IC95% 0,95 1,11). In the second survey, the comparable values were dmft = 2,36 (IC95% 2,20 2,52) and DMFT = 0,35 (IC95% 0,29 0,40), corresponding to a reduction of 38,89% and 66,02% in the primary and permanent dentition, respectively. Treatment needs remain high: In the second survey, as 92,75% of the index DMFT was conformed as decayed teeth. Conclusion: Overall, we detected a downward trend in the dental caries indices, particularly in the permanent dentition. The increase in the availability of fluoride likely contributed to the observed decline in dental caries.     

Dental caries in Mexican schoolchildren: A comparison of 1988–1989 and 1998–2001 surveys

Objectives: To compare two surveys across seven states for the prevalence of dental caries among Mexican schoolchildren. Study Design: Analysis of two cross-sectional surveys: Schoolchildren from 6 to 10 years of age were examined in the 1988–1989 survey and 6- to 10-year-old and 12-year-old students were included in the 1998–2001 survey. The baseline data of seven states were available for analysis. Representative probability samples were conducted statewide in both surveys. The World Health Organization (WHO) method was used to obtain the dental caries index (dmft, DMFT). At present, additional and more recent epidemiological data representative statewide in Mexico are unavailable. Results: The participants were 9798 schoolchildren in the 1988–1989 survey and 16882 schoolchildren in the 1998–2001 survey. The prevalence of caries in children ages 6 to 10 years was 86,6% in the first survey and 65,5% in the second survey, showing a 24,4% reduction. The primary teeth index in the first survey was dmft = 3,86 (IC95% 3,68 4,04) and in permanent teeth, it was DMFT = 1,03 (IC95% 0,95 1,11). In the second survey, the comparable values were dmft = 2,36 (IC95% 2,20 2,52) and DMFT = 0,35 (IC95% 0,29 0,40), corresponding to a reduction of 38,89% and 66,02% in the primary and permanent dentition, respectively. Treatment needs remain high: In the second survey, as 92,75% of the index DMFT was conformed as decayed teeth. Conclusion: Overall, we detected a downward trend in the dental caries indices, particularly in the permanent dentition. The increase in the availability of fluoride likely contributed to the observed decline in dental caries. Key words:Schoolchildren, dental caries, treatment needs, salt fluoridation, Mexico.     

Dental caries diagnosis calibration for clinical field surveys

A method to calibrate examiners for field studies of dental caries was investigated. A total of 200 carious teeth were mounted in 40 plaster blocks so that 920 surfaces were available for examination with a curved probe, using WHO criteria. The results of two examinations of the teeth 1 week apart by 3 experienced and 4 new examiners and 1 year apart by two experienced examiners were compared. The intra-examiner and inter-examiner reproducibility was high for the experienced examiners; between experienced and new examiners the reproducibility fluctuated. Scanning electron microscopic examination of the tips of probes indicated that the sharpness was only slightly decreased within their usual frequency of use. The calibration system used is recommended for the training of examiners for dental caries field studies.     

Predicting the experience of dentinal caries or restorative dental treatment in adolescents using D1 and D3 visual caries assessments

Standardised epidemiological caries assessments used in oral health surveys have been shown to be poor at predicting whether a tooth surface will be treated restoratively when a patient visits a dentist. However, it has been argued that oral health surveys may be more relevant in determining needs at the level of an individual or groups of individuals. The objective of this study was to determine the discriminatory power of visual caries assessments at two thresholds (D₁ & D₃) in adolescents of average age 12.1 years to predict experience of dentinal caries 3 years later or the experience of restorative treatment (not re‐treatment) during the 3‐year period. The data was derived from a prospective 3‐year longitudinal study in which the dental care provided by 41 dentists for 403 adolescents was monitored. Dental caries experience was monitored by annual standardised assessments of caries undertaken by a single trained examiner. ROC analysis showed that caries assessed visually at the D₁ threshold in 12‐year‐olds was a better predictor (P < 0.001) of experiencing some dentinal caries after 3 years (Az = 0.781) than was caries assessed visually at D₃ threshold in 12‐year‐olds (Az = 0.670). Assessing caries visually at either the D₁ or the D₃ threshold had no discriminatory power for predicting whether an individual would experience some restorative treatment during the ensuing 3‐year period (Az for D₁ = 0.507; Az for D₃ = 0.518).