Nigel Pitts

Performance and Reproducibility of a Laser Fluorescence System for Detection of Occlusal Caries in vitro

The diagnosis of occlusal caries at non–cavitated sites remains problematic, especially since clinical visual detection has limited sensitivity. Electrical methods of detection show considerable promise, but specificity is reduced. The aims of this in vitro study were: (1) to assess the validity of a new laser fluorescence device – the DIAGNOdent – (and compare the values with those of a fixed–frequency electrical device); (2) to determine the optimum cut–off points of the new device for different stages of the caries process, and (3) to assess the reproducibility of the new laser device. For validity and determination of optimum cut–off points, 105 extracted teeth with macroscopically intact occlusal surfaces were measured by a single examiner, using both the laser fluorescence device (on both moist and dried teeth) and an Electronic Caries Monitor. The teeth were subsequently examined histologically to determine the specificity, sensitivity and likelihood ratio at the D2 (caries extending through more than half of the enamel thickness) and D3 (caries involving dentin) levels. The values obtained for the laser device ranged from 0.72 to 0.87 (specificity), 0.76 to 0.87 (sensitivity) and 3.0 to 5.6 (likelihood ratio). Those for the ECM ranged from 0.64 to 0.78 (specificity), 0.87 to 0.92 (sensitivity) and 2.4 to 4.1 (likelihood ratio). To determine intra– and interexaminer reproducibility of the DIAGNOdent, 11 dentists recorded two different measurements at the same site on a separate set of 83 extracted molar teeth, and these were compared using Cohen’s kappa (at D2 and D3 levels) and Spearman’s correlation coefficient. The average intra–examiner kappa scores were 0.88 (D2) and 0.90 (D3), with a Spearman correlation of 0.97. For interexaminer reproducibility, the average kappa values were 0.65 (D2) and 0.73 (D3), with a Spearman correlation of 0.84. It is concluded that for occlusal caries (1) the new laser device has a higher diagnostic validity than the ECM, and (2) in vitro, measurements using the device are highly reproducible. Thus, the laser device could be a valuable tool for the longitudinal monitoring of caries and for assessing the outcome of preventive interventions.

An in vivo comparison of radiographic and directly assessed clinical caries status of posterior approximal surfaces in primary and permanent teeth

At general dental practices in Scotland 211 children between the ages of 5 and 15 years were examined by 1 observer. A comparison of the status of 1,468 permanent and 756 primary posterior approximal surfaces was made on the basis of their appearance on posterior bite-wing radiographs and the findings of a direct in vivo visual examination, made after temporary tooth separation had been achieved over 1 week using elastomeric separation. For permanent tooth surfaces, 0% of radiolucencies in the outer half of enamel, 10.5% in the inner half of enamel, 40.9% extending to the outer half of dentine, and 100% extending to the inner half of the dentine were found clinically to be cavitated. The analogous results for primary teeth were that 2.0, 2.9, 28.3, and 95.5%, respectively, of radiolucencies appeared to be cavitated. Although further research with larger numbers of permanent teeth is indicated, these results may contribute to a re-evaluation of the optimal threshold for restorative intervention at approximal sites. Greater numbers of approximal radiolucencies and carious lesions (p less than 0.001) were found in those surfaces which initially had a normal anatomical contact when compared to those which did not.

Are we ready to move from operative to non-operative/preventive treatment of dental caries in clinical practice?

This review focuses on the clinical interactions between patients and the dental team, not on caries prevention at a public health level. Many dentists no longer take a narrow surgical view seeking to apply interventive treatment as a one-off event at a certain trigger point of disease severity and the evidence that caries is an initially reversible, chronic disease with a known multi-factorial aetiology is being appreciated more widely. The caries process should be managed over time in an individualized way for each patient. Very few individuals can be considered to be truly ‘caries free’ when initial lesions as well as more advanced dentine lesions are considered. It is now very clear that, by itself, restorative treatment of the disease does not ‘cure’ caries. The caries process needs to be managed, in partnership with patients, over the changing challenges of a lifetime. The answer to the question posed in the title should be, in many cases, that we are ready to move to non-operative/preventive care (if we have not done so already). However, this should be for appropriate stages of lesion extent and in patients who respond to advice on recall frequency and preventive behaviours.

A reappraisal of the value of the bitewing radiograph in the diagnosis of posterior approximal caries

The aim of this paper was to re-assess the available literature examining the value of the bitewing radiograph in the diagnosis of approximal caries and to compare the relative values of radiographic and clinical examinations. To this end, results from 29 research studies have been re-presented and tabulated. These results show that the use of the bitewing radiograph is essential if much approximal caries is not to be missed. It is particularly important in the detection of the small lesion which may be managed preventively rather than operatively. Although there is a proper need to ensure that radiographic exposures are minimised, the evidence suggests that both clinicians and epidemiologists must balance this need with the ethical issues associated with failing to employ an established diagnostic aid

Occlusal caries diagnosis: a changing challenge for clinicians and epidemiologists

The diagnosis of occlusal caries is an integral part of an epidemiologists task, whether carrying out cross-sectional national caries prevalence surveys to assist with planning and the evaluation of service provision, or clinical trials of caries preventive agents. Similarly, the clinician also carries out this same overall diagnostic procedure in order to plan care for individual patients, although he/she will usually have access to improved facilities and diagnostic aids. This paper reviews the different problems now being encountered by both epidemiologists and clinicians in the face of changes in the presentation of the disease at this site and the qualifications which should now be appreciated when extrapolating from the results of surveys employing comparatively gross criteria. It explores recent developments in diagnostic aids and makes suggestions as to how further information might be obtained in future which would aid the valid comparison of diagnoses made by these two groups of dentists.

PRIME - PRocess modelling in ImpleMEntation research: selecting a theoretical basis for interventions to change clinical practice

BackgroundBiomedical research constantly produces new findings but these are not routinely translated into health care practice. One way to address this problem is to develop effective interventions to translate research findings into practice. Currently a range of empirical interventions are available and systematic reviews of these have demonstrated that there is no single best intervention. This evidence base is difficult to use in routine settings because it cannot identify which intervention is most likely to be effective (or cost effective) in a particular situation. We need to establish a scientific rationale for interventions. As clinical practice is a form of human behaviour, theories of human behaviour that have proved useful in other similar settings may provide a basis for developing a scientific rationale for the choice of interventions to translate research findings into clinical practice.The objectives of the study are: to amplify and populate scientifically validated theories of behaviour with evidence from the experience of health professionals; to use this as a basis for developing predictive questionnaires using replicable methods; to identify which elements of the questionnaire (i.e., which theoretical constructs) predict clinical practice and distinguish between evidence compliant and non-compliant practice; and on the basis of these results, to identify variables (based on theoretical constructs) that might be prime targets for behaviour change interventions.MethodsWe will develop postal questionnaires measuring two motivational, three action and one stage theory to explore five behaviours with 800 general medical and 600 general dental practitioners. We will collect data on performance for each of the behaviours. The relationships between predictor variables (theoretical constructs) and outcome measures (data on performance) in each survey will be assessed using multiple regression analysis and structural equation modelling. In the final phase of the project, the findings from all surveys will be analysed simultaneously adopting a random effects approach to investigate whether the relationships between predictor variables and outcome measures are modified by behaviour, professional group or geographical location.

Total tooth loss in the United Kingdom in 1998 and implications for the future.

The 1998 Adult Dental Health Survey, published this year, showed that the number of people without teeth should fall over the next three decades, to only 4% of the UK population. Patterns of tooth loss and retention are also changing. This article, the first of a series on the interpretation of the Adult Dental Health Survey, discusses the implications of these trends for dentistry.

The fate of 1,587 unrestored carious deciduous teeth: a retrospective general dental practice based study from northern England

Objective To investigate the outcome of non-restoration of carious deciduous teeth by means of a retrospective analysis of clinical case notes of children regularly attending two general dental practices and receiving preventive care.Design Using a carefully defined protocol the fate of deciduous teeth diagnosed as carious into dentine but symptomless and left unrestored was determined from the sequential examination of the clinical records of 481 children attending at least annually.Results The age at initial diagnosis of carious teeth ranged from 1–12 years with the majority of cavities (1,005) presenting by 6 years of age. In all, 1,587 teeth were followed until loss from the mouth. Of these, 190 (12%) were extracted because of pain and a further 60 (4%) became painful and were treated, leaving 1,337 (84%) that remained symptomless until being lost. Of the 1,337 symptomless teeth, 178 were extracted under general anaesthesia at the same time as painful ones. The final group of 1,159 (74%) teeth were exfoliated without causing pain after a mean survival time of 1,332 days. Excluding from the analysis the 178 extracted, but symptomless teeth, leaves a total of 1,409 teeth of which 18% gave pain and were extracted or treated and the remaining 82% exfoliated. The strongest determinant of pain was age on diagnosis, the other factors being tooth type and extent of the cavity when first seen. The carious teeth most likely to cause symptoms were found to be molars that developed cavities with pulpal involvement by the age of 3 years, 34% of which caused pain. In contrast, those least likely to cause pain were carious molar teeth presenting without pulpal involvement after 8 years, only 6% of which produced symptoms.Conclusion In these patients, the majority of unrestored carious deciduous teeth remain symptomless until shed. The results provide evidence to aid the treatment planning of carious deciduous teeth in children regularly receiving regular preventive dental care.

Developments in radiographic caries diagnosis

The developments that have been taking place in radiographic caries diagnosis, within the context of the changes occurring in both the disease process and the available technology, are reviewed. The decline in caries prevalence seen in many western countries has been accompanied by changes in the pattern and behaviour of lesions. More lesions are now seen on occlusal surfaces, more are concealed (and thus imperceptible to conventional diagnostic techniques), while the average progression rates for approximal lesions have also slowed. Systems employed for caries diagnosis must take account of these changes and the varying needs of users employing different diagnostic thresholds. This paper reviews and discusses developments in: conventional film radiography; xeroradiography; indirect digital imaging (with computer image analysis and subtraction radiography), and direct digital imaging. It is concluded that: for the detection in high caries prevalence groups of both approximal caries (especially small lesions in enamel) and dentinal occlusal lesions in teeth with little or no surface breakdown, radiography is still a significant and reasonably accurate diagnostic method; and that, in spite of the more limited resolution, digital imaging methods seem to perform as well or better than conventional film radiography. Digital systems possess a number of advantages, primarily the possibility for image enhancement and significant dose reduction. It may be predicted that digital imaging techniques will enter the clinical routine in the near future.

Global oral health inequalities: dental caries task group--research agenda.

The IADR Global Oral Health Inequalities Task Group on Dental Caries has synthesized current evidence and opinion to identify a five-year implementation and research agenda which should lead to improvements in global oral health, with particular reference to the implementation of current best evidence as well as integrated action to reduce caries and health inequalities between and within countries. The Group determined that research should: integrate health and oral health wherever possible, using common risk factors; be able to respond to and influence international developments in health, healthcare, and health payment systems as well as dental prevention and materials; and exploit the potential for novel funding partnerships with industry and foundations. More effective communication between and among the basic science, clinical science, and health promotion/public health research communities is needed. Translation of research into policy and practice should be a priority for all. Both community and individual interventions need tailoring to achieve a more equal and person-centered preventive focus and reduce any social gradient in health. Recommendations are made for both clinical and public health implementation of existing research and for caries-related research agendas in clinical science, health promotion/public health, and basic science.