Examiner performance in calibration exercises compared with field conditions when scoring caries experience

Longitudinal study for dental caries calibration of dentists unexperienced in epidemiological surveys

This study aimed to make a longitudinal analysis of interexaminer calibration reproducibility in diagnosing dental caries in posterior teeth, by examiners without previous experience in epidemiological studies. A group of 11 inexperienced examiners underwent theoretical-practical training and calibration assessments, assisted by a standard examiner. An examiner who did not participate directly in the research selected 5-year-old children with and without caries. The D3 diagnostic threshold was used to evaluate dental caries, based on the World Health Organization (WHO) criteria. The initial calibration (baseline) was performed after the theoretical-practical training session, and consisted of examining 20 children; the second calibration occurred three months later, and involved evaluating another 18 children. The interexaminer agreement was obtained by kappa statistics, and by overall percentage agreement. The paired t-test was applied to compare the values for kappa means and overall percentage agreement between the time points studied. At baseline, the values for kappa (> 0.81) and overall percentage agreement (> 95.63%) were considered high. At the 3-month calibration assessment, all the examiners showed some decrease in both kappa (p < 0.0001) and overall percentage agreement (p = 0.0102). The calibration process currently proposed by the WHO is effective. However, reproducibility was not maintained over time for inexperienced examiners evaluating the posterior teeth of 5-year-old children, under epidemiological conditions.

Effects of a 2-Year Early Childhood Vitamin D3 Intervention on Tooth Enamel and Oral Health at Age 6-7 Years

INTRODUCTION

The aim of the study was to compare the effects of a 30 µg/day versus 10 µg/day vitamin D supplementation, given during the two first years of life, on oral health at the age of six to 7 years.

METHODS

In 2013-2016, we conducted a randomized, double-blinded, clinical trial from age 2 weeks to 2 years of daily vitamin D3 supplementation (10 vs. 30 µg), including 975 healthy infants. For the present follow-up study at age 6-7 years, a sample of 123 children underwent oral examination by investigators blinded to the intervention group. Tooth enamel defect and caries findings, oral rinse active matrix metalloproteinase-8 levels, and tooth eruption were recorded. The intervention groups were compared with χ2 and Mann-Whitney U tests. Associations of the oral health outcomes were evaluated with correlation analysis and logistic regression.

RESULTS

Of the children (median age 7.4 years, 51% boys), 56% belonged to the 30 µg intervention group. Developmental defect of enamel (DDE) was found in 39% of the children in the 10 µg intervention group and in 53% of the 30 µg group (p = 0.104). In total, 94% of children were vitamin D sufficient (25[OH]D ≥50 nmol/L) and 88% had caries-free teeth. No associations were found between vitamin D intervention group in infancy and oral health or the presence of DDE.

CONCLUSION

Daily supplementation with 10 µg vitamin D3 in the Northern Hemisphere seems adequate in healthy children younger than 2 years in ensuring good oral health at early school age.

Dental Faculty Accuracy When Using Diagnostic Codes: A Pilot Study

The aim of this study was to examine the accuracy of dental faculty members' utilization of diagnostic codes and resulting treatment planning based on radiographic interproximal tooth radiolucencies. In 2015, 50 full-time and part-time general dentistry faculty members at one U.S. dental school were shown a sequence of 15 bitewing radiographs; one interproximal radiolucency was highlighted on each bitewing. For each radiographic lesion, participants were asked to choose the most appropriate diagnostic code (from a concise list of five codes, corresponding to lesion progression to outer/inner halves of enamel and outer/middle/pulpal thirds of dentin), acute treatment (attempt to arrest/remineralize non-invasively, operative intervention, or no treatment), and level of confidence in choices. Diagnostic and treatment choices of participants were compared to "gold standard" correct responses, as determined by expert radiology and operative faculty members, respectively. The majority of the participants selected the correct diagnostic code for lesions in the outer one-third of dentin (p<0.0001) and the pulpal one-third of dentin (p<0.0001). For lesions in the outer and inner halves of enamel and the middle one-third of dentin, the correct rates were moderate. However, the majority of the participants chose correct treatments on all types of lesions (correct rate 63.6-100%). Faculty members' confidence in their responses was generally high for all lesions, all above 90%. Diagnostic codes were appropriately assigned by participants for the very deepest lesions, but they were not assigned accurately for more incipient lesions (limited to enamel). Paradoxically, treatment choices were generally correct, regardless of diagnostic choices. Further calibration is needed to improve faculty use and teaching of diagnostic codes.

The ethics of in vivo calibrations in oral health surveys

Objectives:

To analyze the ethics of in vivo calibration, using the discourse of the administrators of the National Oral Health Survey (SBBrasil 2010) as a starting point.

Method:

This is a qualitative research involving semi-structured individual interviews with 12 members of the Steering Group and Technical Advisory Committee of the Ministry of Health, and two coordinators, one State and the other Municipal. The discourse of the collective subject technique was used for data analysis.

Results:

When asked about the experiences of SBBrasil 2010, which included ethical aspects, respondents identified the forms of standardization and training of teams who collected field data. For them, there is little scientific evidence to ethically support the way the training stage, including calibration, is carried out in oral health epidemiological surveys, as a certain unease can be predicted in participants of these studies.

Conclusion:

The ethics of a research also derives from its methodological rigor; the training process; and calibration in particular, is a fundamental technical and ethical requirement in surveys such as the SBBrasil 2010. The unease of the volunteers in face of test repetition does not ethically invalidate the in vivo calibration, but mechanisms to minimize it must be developed.

Natural history of dental caries in very young Australian children

BACKGROUND

Whilst the global burden of caries is increasing, the trajectory of decay in young children and the point at which prevention should occur has not been well established.

AIM

To identify the 'natural history' of dental caries in early childhood.

DESIGN

A birth cohort study was established with 467 mother/child dyads followed at 1, 6, 12, 18, and 36 months of age. Parent-completed surveys captured demographic, social, and behavioural data, and oral examinations provided clinical and data.

RESULTS

Eight per cent of children (95% confidence interval (CI): 5-12%) at 18 months and 23% (95% CI: 18-28%) at 36 months experienced decay. Interesting lesion behaviour was found between 18 and 36 months, with rapid development of new lesions on sound teeth (70% of teeth, 95% CI: 63-76%) and regression of many lesions from non-cavitated lesions to sound (23% of teeth, 95% CI: 17-30%). Significant associations were found between soft drink consumption and lesion progression.

CONCLUSIONS

Findings suggest optimal time periods for screening and prevention of a disease which significantly impacts multiple health and well-being outcomes across the life course.

Comparison of the performance of intraoral X-ray sensors using objective image quality assessment

OBJECTIVES

The main aim of this study was to evaluate the performance of 10 individual sensors of the same make, using objective measures of key image quality parameters. A further aim was to compare 8 brands of sensors.

STUDY DESIGN

Ten new sensors of 8 different models from 6 manufacturers (i.e., 80 sensors) were included in the study. All sensors were exposed in a standardized way using an X-ray tube voltage of 60 kVp and different exposure times. Sensor response, noise, low-contrast resolution, spatial resolution and uniformity were measured.

RESULTS

Individual differences between sensors of the same brand were surprisingly large in some cases. There were clear differences in the characteristics of the different brands of sensors. The largest variations were found for individual sensor response for some of the brands studied. Also, noise level and low contrast resolution showed large variations between brands.

CONCLUSIONS

Sensors, even of the same brand, vary significantly in their quality. It is thus valuable to establish action levels for the acceptance of newly delivered sensors and to use objective image quality control for commissioning purposes and periodic checks to ensure high performance of individual digital sensors.

Oral health research: A source for innovative new statistical developments

This article reviews the challenges and opportunities that oral health research may offer to a statistician. To illustrate this, we focus on the Signal Tandmobiel® study, a longitudinal oral health survey that triggered many statistical explorations and developments over the last two decades. For example, non-standard distributions are more the rule than the exception in oral health research. In addition, often measurement error problems need to be addressed. The hierarchical structure of the oral health data also poses non-standard challenges. For instance, caries experience in the mouth is spatially correlated with, however, a specific metric defining the distance between two occurrences. In addition, since caries experience in the context of an epidemiological study is only measured at intervals, analysis of survival involves interval-censoring. Finally, when analyzing a realistic data set in oral health, all the above issues may have to be dealt with simultaneously.

Assessment of early occlusal caries pre- and post-sealant application--an imaging approach

BACKGROUND AND OBJECTIVE

Clinicians have difficulty assessing and monitoring early occlusal caries. Traditional clinical exam and radiographs are unable to detect the subtle alterations in enamel indicative of de- or re-mineralization, particularly under dental sealants. Although clinicians have used laser fluorescence (LF) to address this gap, this modality has demonstrated weak correlation with histology. The International Caries Detection and Assessment System (ICDAS-II) has demonstrated high sensitivity and specificity for caries detection, but since it is based on visual assessment, it is of no use in areas beneath the most commonly used dental sealants which are opaque. Optical coherence tomography (OCT) is an emergent assessment tool which has demonstrated great promise in detecting and quantifying caries, including areas beneath commonly used dental sealants and composites. However, OCT has not yet been widely integrated into clinical dental practice, perhaps because OCT imaging does not provide an easily accessible diagnostic outcome for clinicians. The objective of this ex vivo study was to use OCT-images of sound and carious occlusal surfaces in combination with a simple algorithm to compare the caries detection ability of OCT with tools clinicians may be more familiar with (LF and radiography), and with an established valid and reliable clinical assessment tool (ICDAS-II).

STUDY DESIGN/MATERIALS AND METHODS

One hundred twenty extracted teeth with sound or naturally carious occlusal surfaces were imaged with OCT, LF, radiography, and examined clinically with the ICDAS-II. Teeth were randomized to one of two dental sealants recommended for use with LF. A novel simple algorithm was used to interpret OCT-based images. The accuracy of caries severity assessments of the OCT-based diagnosis, LF, ICDAS-II, and digital radiography were compared to the 4-point histological analysis gold standard.

RESULTS

OCT and ICDAS-II caries severity assessments demonstrated high sensitivity (94.0%; 92.3%) and specificity (85.0%; 83.3%), LF demonstrated low sensitivity (65.2%) but high specificity (97.6%), and digital radiography demonstrated low sensitivity (67.1%) with moderate specificity (79.5%) on unsealed occlusal surfaces. OCT-based caries severity assessments of sealed teeth demonstrated high specificity (97.6%), sensitivity (89.9%), excellent positive predictive value (98.6%), and negative predictive value (83.3%). Despite our use of LF recommended dental sealants, in the presence of sealants, LF assessment of caries severity demonstrated high sensitivity (95.1%), but extremely low specificity (10.3%), positive predictive value (68.8%), and negative predictive value (50.0%).

CONCLUSION

This study found that OCT-based imaging combined with a simple diagnostic algorithm accurately assessed the severity of natural early caries on occlusal surfaces in extracted teeth both in the absence and presence of dental sealant. The findings of this study support the clinical use of OCT imaging for assessment and monitoring progression of early non-cavitated caries lesions on occlusal surfaces including areas under dental sealants.

Correction for misclassification of caries experience in the absence of internal validation data

OBJECTIVES

To quantify the effects of risk factors and/or determinants on disease occurrence, it is important that the risk factors as well as the variable that measures the disease outcome are recorded with the least error as possible. When investigating the factors that influence a binary outcome, a logistic regression model is often fitted under the assumption that the data are collected without error. However, most categorical outcomes (e.g., caries experience) are accompanied by misclassification and this needs to be accounted for. The aim of this research was to adjust for binary outcome misclassification using an external validation study when investigating factors influencing caries experience in schoolchildren.

MATERIALS AND METHODS

Data from the Signal Tandmobiel(®) study were used. A total of 500 children from the main and 148 from the validation study were included in the analysis. Regression models (with several covariates) for sensitivity and specificity were used to adjust for misclassification in the main data.

RESULTS

The use of sensitivity and specificity modeled as functions of several covariates resulted in a better correction compared to using point estimates of sensitivity and specificity. Age, geographical location of the school to which the child belongs, dentition type, tooth type, and surface type were significantly associated with the prevalence of caries experience.

CONCLUSIONS

Sensitivity and specificity calculated based on an external validation study may resemble those obtained from an internal study if conditioned on a rich set of covariates.

CLINICAL RELEVANCE

Main data can be corrected for misclassification using information obtained from an external validation study when a rich set of covariates is recorded during calibration.