A proposed method for assessing the quality of sealants--the CCC Sealant Evaluation System.

OBJECTIVES: The aim of this paper is to introduce the C (colour) C (coverage) C (caries) Sealant Evaluation System and to present results of its use on a sample of adolescent patients in Scotland. METHODS: Baseline data are presented from a 3-year prospective study in general dental practices across Scotland. Subjects were examined under standardised conditions by one trained and calibrated examiner. RESULTS: 78.6% of the subjects had one or more sealed teeth, over half of these sealants being judged inadequate. There was a low prevalence of dentine caries associated with the sealed teeth (2.8%). The CCC sealant Evaluation System proved practical as demonstrated by its use during the project and had substantial intra-examiner reproducibility. CONCLUSIONS: There was a high level of sealant provision; however, this provision may not be optimal in terms of both targeting of provision and sealant maintenance. The CCC sealant Evaluation System appeared to be a useful assessment tool for assessing sealed surfaces.

General dental practitioners diagnostic and treatment decisions related to fissure sealed surfaces.

OBJECTIVES: The purpose of this in-vitro study was to assess the validity and reproducibility of the diagnosis and treatment planned for occlusal surfaces prior to and following the placement of a clear sealant by a sample of general dental practitioners (GDPs). METHODS: 160 permanent posterior teeth were examined by 25 GDPs. The GDPs were not given any criteria and were therefore free to diagnose and plan care, as they felt appropriate. Each GDP conducted four examinations, two prior to and two after sealing. The teeth were serially sectioned to provide the validating criterion. RESULTS: After sealant placement, there was a statistically significant increase in specificity and decrease in sensitivity of both diagnostic and treatment decisions. The reproducibility expressed by the kappa-statistic was of the order of 0.5 prior to and after sealing with regard to diagnostic decisions. There was a general tendency to diagnose less disease after placement of a sealant (P<0. 001). There was also significantly less care (preventive or restorative) planned after sealant placement (P<0.001). CONCLUSIONS: The placement of a sealant resulted in the diagnosis of less disease and less restorative treatment. This may be appropriate as evidence exists to support the use of sealants as caries therapeutic agents.

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 dental caries status of Scottish adolescents reported to be regular attenders. Initial results from a primary dental care based research network.

AIM: To investigate the caries status of, and the delivery of care to, a group of regularly attending adolescent dental patients. To conduct research in primary dental care. A subsidiary aim was to compare the caries status of this sample to population samples. SETTING: General dental practices across Scotland. DESIGN: A 3-year cohort study. SUBJECTS: 41 volunteer general dental practitioners and 616 adolescent patients (mean age = 12.1 years at baseline) defined by the practitioners as 'regular' attenders. RESULTS: All practices remained in the study. 403 subjects were seen at both baseline and final examination and 329 were examined at all 4 annual examinations. The mean D3MFT (dentine caries threshold) was 1.8 at baseline and 3.9 at the final examination, three years later. Of the 541 subjects seen at baseline 62% had experienced either restored or unrestored dentinal caries. Thirty-four percent of all those examined at baseline had all the unrestored dentinal caries. The majority of the disease was to be found in the molar teeth, particularly the first permanent molars. The provision of sealants was relatively high with 85% of subjects having at least one sealed tooth by the final examination. Although disease levels were related to socio-economic status, the Care Index was not. CONCLUSIONS: The 'regularly attending' subjects had a better normative level of dental health than their peers in the Scottish population. However, wide variation was found. The project also demonstrated the feasibility of undertaking research in partnership with general dental practitioners.

The reliability of two methods of utility assessment in dentistry.

OBJECTIVE: The objective of this study was to investigate the modification of two utility assessment techniques (visual analogue scale and daily time trade-off) used in medicine to the dental setting, with a focus on their test-retest reliability and ease of use. BASIC RESEARCH DESIGN: The study involved a postal questionnaire survey which incorporated a dental visual analogue scale (DVAS) to assess utility values for 12 specified tooth states, and a specifically designed instrument, the dental freetime trade-off (DFTO) to assess utility of the participants' current dental health state. PARTICIPANTS: A total of 582 regularly attending adolescent dental patients were sent the questionnaire. A further 100 of those who fully completed the relevant sections of the questionnaire were sent a repeat questionnaire to facilitate assessment of test-retest reliability. RESULTS: A final response rate of 74.7% was achieved with the mean age of respondents being 17 years. Fifty per cent of those sent a repeat questionnaire for the purposes of reliability assessment returned the questionnaire. Test-retest reliability of both utility assessment techniques appeared acceptable. Spearman correlation coefficients for the dental freetime trade-off (DFTO) and the dental visual analogue scale (DVAS) were (0.67 and 0.83 respectively. Promising results, in terms of utility values, were elicited from the DVAS whilst utility values elicited using the DFTO were highly skewed. CONCLUSIONS: The newly developed modification to the daily time trade-off technique, the DFTO, showed a good level of test-retest reliability and ease of completion although the highly skewed utility results produced may indicate a design flaw. The DVAS however, appears to show promise, in terms of test-retest reliability, ease of completion and resultant utility values.

Integrity, maintenance and caries susceptibility of sealed surfaces in adolescents receiving regular care from general dental practitioners in Scotland.

Pit and fissure sealants (sealants) are recognized as an effective caries preventive measure. The aim of this study was to assess the fate of occlusal surface sealants in a sample of 'regularly' attending adolescent patients (mean age 12.5 years at baseline) of 41 general dental practitioners, participating in a 3-year prospective clinical trial. A subsidiary aim was to compare the caries status of completely sealed surfaces with that of inadequately sealed surfaces over the same period. Baseline and three annual follow-up examinations were conducted by one trained and calibrated examiner under optimal conditions (dental chair, operating light, and compressed air). Sealed occlusal surfaces were evaluated for sealant type, sealant coverage, and caries status of the surface. Data for the initial and final year examinations were available for 402 subjects, who had 1377 sealants at baseline. Surfaces with optimal sealant coverage at baseline (n = 592) were significantly less likely to have become decayed (dentinal caries) or to have been restored by year 4 than surfaces with less than complete coverage (P < 0.001). Considering sealant maintenance during the study, 484 of the sealants were of optimal coverage (covered the fissure system) at the final examination. However, only 135 surfaces demonstrated evidence of maintenance by attaining optimal coverage. It is concluded that the fissure sealants in this sample may not have received the regular maintenance required to ensure full surface coverage and thus provide maximal caries protection, as inadequately sealed surfaces were more likely to decay than completely sealed surfaces.

Developmental defects of enamel in regularly attending adolescent dental patients in Scotland; prevalence and patient awareness.

Contemporary dental literature contains many reports of the prevalence of developmental defects of enamel in a variety of populations. Little information is available relating to patients' perceptions of such defects. The aim of this study was to compare the prevalence of developmental defects of enamel in a sample of regularly attending adolescent dental patients with the patients' own views as to whether they thought they had marks on their teeth. The index used for the assessment of defects, the SCOTS Version of the Modified DDE Index (SCOTS/DDE Index), includes both a dentist and patient assessment of defects. Four hundred and eighty-five adolescent dental patients of 41 general dental practitioners in Scotland were examined under standardised conditions in a mobile dental surgery by one trained and calibrated examiner. Approximately half the sample had some sort of developmental defect of enamel, as classified by the SCOTS/DDE Index. However, only 14 per cent of the sample claimed to be aware of marks on their front teeth which would not brush off.

Decision processes in the management of dental disease. Part 1: QALYs, QATYs and dental health state utilities.

A necessary step in attempting to frame a rational decision about managing dental disease is to evaluate the clinical outcomes. This article discusses how the patient's view of the worth or value of a dental health state can be quantified, how this can contribute to the development of the Quality Adjusted Tooth Year (QATY) as a dental variation of the Quality Adjusted Life Year (QALY) known in medicine, and how the dental practitioner can use this technique to decide which treatment is best for a particular patient.

The effect of placing a clear pit and fissure sealant on the validity and reproducibility of occlusal caries diagnosis.

The purpose of this in vitro study was to assess the validity and reproducibility of the diagnosis of fissure caries prior to and following the placement of a clear sealant. One hundred and twelve extracted molar teeth were examined by 7 experienced clinicians. Each examiner conducted four visual examinations, 2 prior to and 2 after sealing, allowing an assessment of reproducibility. The teeth were subsequently serially sectioned to provide the histological validation. After placement of a sealant, a significant (p < 0.05) loss of sensitivity was found for the diagnosis of enamel lesions and dentine lesions, but specificity was not altered. The overall reproducibility expressed by the kappa statistic was 0.60 and 0.47, before and after sealing, respectively. The examiners significantly (p < 0.001) underestimated the severity of lesions detected after sealing compared to their assessment prior to sealing. The investigation suggests that sealed surfaces require careful assessment and monitoring.

Caries management strategies used by a group of Scottish dentists.

This study was designed to determine how dentists would manage carious lesions of differing severity and whether they would consider using non-invasive methods to manage lesions which were not severe enough to require a restoration. A group of 211 general dental practitioners were interviewed and asked to identify the point at which they would provide restorative treatment in a 12-year-old patient from a list of descriptions of lesions affecting buccal/lingual, occlusal and approximal surfaces. They were then asked how they would manage lesions which they would not restore. Most of the dentists said they would attempt to use some form of active non-invasive management technique. Principal among these would be teaching the patient how to maintain their oral hygiene and giving them dietary advice. The majority also felt that fluoride varnish or gel would help control a buccal or lingual surface lesion and that placement of a fissure sealant without any mechanical removal of tooth tissue would be a satisfactory way to control a lesion affecting an occlusal surface. The findings support the view that it may be useful to classify caries into two types: lesions for which preventive care is advised (PCA) or lesions for which operative care is advised (OCA).

Assessment of reports by dentists of their restorative treatment thresholds.

Questionnaires have been used to determine the point when dentists think a filling ought to be placed (restorative treatment threshold). This study assesses the method. 211 general dental practitioners were interviewed and asked to identify the point at which they would instigate restorative treatment in a 12-yr-old patient from a list of descriptions of lesions affecting buccal/lingual, occlusal and approximal surfaces. They were also asked to judge the likely depth and lateral spread of the lesion they chose and to identify a photograph resembling it (buccal/lingual and occlusal surfaces) or a line drawing and description of its expected surface appearance (approximal surfaces). The Pearson correlation coefficients between reported treatment threshold and the characteristics expected to be associated with them were poor. This suggests that there may be considerable variation in opinion between dentists about the underlying condition of carious lesions of similar surface appearance. There was no evidence that the treatment opinions of these dentists have changed markedly between 1987 and early 1991.

Assessment of dental health state utilities.

The term "health state utility" implies the assigning of a numerical value to a state of health. Assessment of the success of health care procedures, using health state utilities, enables evaluation of available treatments and procedures in terms of differing health outcomes and therefore facilitates cost-benefit analyses. Although measurement of general health state utilities has become increasingly common in medicine using a variety of techniques, few attempts have as yet been made in dentistry to place valuations on different dental health states. The absence of tried and tested methods for measuring tooth quality make the benefits gained from preventive and restorative dental programmes difficult to quantify. The aim of this study was to assess the average utility values, held by a group of dentists and a group of members of the general public, for four different tooth states which it was hypothesised would have different values. These were 1) a decayed and painful posterior tooth; 2) a decayed and non-painful posterior tooth; 3) a posterior tooth which had been restored and would need further restorative treatment and 4) a permanently restored posterior tooth. A standard gamble questionnaire was used to elicit the utility values which were then substituted as "weightings" in a modified version of the "T-health" index (1). The results show that it is possible to assess dental health state utility values using the standard gamble method and that the average utility values of the dentists in the study were consistently higher than those of the general public.(ABSTRACT TRUNCATED AT 250 WORDS)

Provision of crowns in Scotland--a ten year longitudinal study.

The annual reports of the Scottish Dental Practice Board have shown a dramatic increase in the number of crowns provided in the general dental service between the years 1978 and 1988. This paper investigates the changes in crown provision for a sample of dentate adults in Scotland whose dental treatment records have been monitored longitudinally. One hundred and sixteen out of a sample of 720 patients received one or more crowns over the ten year period between 1978 and 1988. A total of 213 crowns were placed, the majority of which were constructed of porcelain. Forty eight of them were replacements for crowns which had been supplied prior to or during the study period. A preliminary life table analysis estimates the median survival time of the crowns to be at least 10 years.

The Chief Scientist reports.... Problems in mounting and maintaining longitudinal studies--examples from dental health services research.

There already exists a body of literature on the conduct of classical epidemiological studies. However, guidelines tend towards detailing how such studies should be conducted and may not prepare the reader for the less-than-perfect scenarios that will inevitably be encountered. The Dental Health Services Research Unit in Dundee has been involved in longitudinal studies of dental treatment and dental health since its inception in 1979. The problems encountered in this research are considered under the headings of mounting the studies, samples, data collection, external changes, internal changes, dissemination and curtailment. It is hoped that a description of the often unpredictable problems associated with a particular set of studies will provide an insight which may assist others embarking on analogous projects in health services research.

Scottish dentists' use of and opinions regarding bitewing radiography.

This study examined Scottish dentists' claimed use of and opinions regarding bitewing radiography. Information was obtained from a questionnaire sent to all dentists practising in Scotland in 1987 and from national statistics published in the Annual Reports of the Dental Practice Boards in the UK. The response rate to the questionnaire was 72% (926 general dental practitioners and 201 clinical community dental officers). Respondents considered radiography to be of value for the detection of approximal caries, assessment of caries progression and evaluation of alveolar periodontal support. They considered it to be of less value for a variety of other tasks, including detecting occlusal caries, unerupted teeth or calculus. One hundred and fifty-eight dentists (15% of respondents) claimed not to have taken any bitewings of their 12-year-old patients in the preceding year. Those respondents who did claim to have exposed some bitewings said that approximately one-quarter of this patient group had received the examination in the past year. The overall Health Service statistics appear to confirm that the utilization of radiography by dentists practising in Scotland is somewhat lower than that by dentists in England and Wales, a factor which requires further investigation.

A profile of orthodontic treatment in the general dental service in Scotland 1979-1987.

The study casts and records of two samples of patients who had received orthodontic treatment involving the use of appliances within the General Dental Service (GDS) in Scotland during 1979/81 and 1986/87 were examined to study the pattern of treatment, and to determine whether there had been any change over this period. Both samples contained a wide range of malocclusions which were treated mostly with removable appliances. Although few fixed appliances were used and few lower arch treatments were carried out there was a trend towards a greater use of these appliances and an increase in these treatments in 1986/87 compared with 1979/81. There was no change in the infrequent use of headgear while functional appliances were used in only six of the treatments in the 1986/87 sample as compared to none in the 1979/81 sample. In the more recent sample many more treatments were undertaken by 'specialist' General Dental Practitioners (i.e. those who work in the GDS, but limit their practice to orthodontics) and fewer treatments were undertaken under the direction of a Consultant Orthodontist.

Origin, training, and subsequent practice location of Scotland's General and Community dentists.

In view of the continuing concern, in the United Kingdom (UK) and many other countries, over the maldistribution of dental manpower and the far-reaching plans now being contemplated to correct existing imbalances, it was felt to be necessary to document the current situation in Scotland. This study set out to identify the origins, place of training, and subsequent practice locations of Scotland's General and Community dentists. A questionnaire was sent to a list of all General Dental Practitioners (GDPs) and Clinical Community Dental Officers (CCDOs) in Scotland. The final response rate was 72%. 85% of respondents had received the majority of their secondary school education in Scotland, and a total of 92.5% of respondents had received their undergraduate dental training at one of the three Scottish dental schools. Factors elicited as being associated with practice location choice included school of dental training, location of a dentist's original home and relatives, and, to some extent, market forces in terms of "demand for dentists" in some areas in Scotland.

A profile of dentists working in the general and community dental services in Scotland in 1987.

A questionnaire was sent to a list of what was considered to be all (1726) practitioners in the General Dental Service (GDS) and Community Dental Service (CDS) in Scotland. The overall response rate was 72%. A comparison of certain characteristics of the respondents with those of the entire group of dentists who were sent questionnaires suggested that the respondents comprised an acceptable cross-section. Proportionally more females worked in the CDS than in the GDS and many of the differences between the general characteristics of practitioners in the two services appeared to reflect differences which are known to exist between the career patterns of male and female dental practitioners. Most respondents (84.7%) claimed to have attended a post-graduate course within the last 5 years, although only 33.4% claimed to have attended more than one course per year. Over three-quarters of the respondents (76.0%) claimed that they belonged to a professional society, whilst 98.5% stated that they regularly read a professional journal or practice newspaper of some description.