A competing risk survival analysis model to assess the efficacy of filling carious primary teeth.

In recent years a strategy of selective, symptom-based intervention of carious primary teeth has been developed amongst some British general dental practitioners. Practice-based studies appear to provide evidence that policies of restoration of symptomless carious primary teeth do not confer any significant benefits above those associated with non-restorative care. However, results from these studies contrast with those of many clinical trials and prospective studies of primary molar restorations. In the current investigation, cohort study data from 5,168 carious primary molar teeth from 2,654 British children aged 4-5 years at baseline, augmented with Dental Practice Board treatment data, was utilised to assess the effect of restorative treatment on the likelihood of carious teeth subsequently progressing to either exfoliation or extraction. The effect of demographic and tooth level covariates on the fate of these teeth was also assessed. Multivariate multilevel parametric survival models were applied to the analysis of the carious-exfoliation and carious-extraction transitions to which the teeth were subject, assuming an underlying data hierarchy with teeth nested within individuals. Time of occurrence of caries affected survival experience, with teeth in which caries occurred later in life being associated with higher survival rates to extraction. Amongst filled teeth, later fillings were also associated with higher survival rates to extraction. Demographic and tooth level variables had a limited effect on survival experience. Treatment was found to be significantly associated with survival with respect to extraction, with survival rates of over 80% at 14 years, double those of untreated teeth.

Modelling childhood caries using parametric competing risks survival analysis methods for clustered data.

Caries in primary teeth is an ongoing issue in children's dental health. Its quantification is affected by clustering of data within children and the concurrent risk of exfoliation of primary teeth. This analysis of caries data of 103,776 primary molar tooth surfaces from a cohort study of 2,654 British children aged 4-5 years at baseline applied multilevel competing risks survival analysis methodology to identify factors significantly associated with caries occurrence in primary tooth surfaces in the presence of the concurrent risk of exfoliation, and assessed the effect of exfoliation on caries development. Multivariate multilevel parametric survival models were applied at surface level to the analysis of the sound-carious and sound-exfoliation transitions to which primary tooth surfaces are subject. Socio-economic class, fluoridation status and surface type were found to be the strongest predictors of primary caries, with the highest rates of occurrence and lowest median survival times associated with occlusal surfaces of children from poor socio-economic class living in non-fluoridated areas. The concurrent risk of exfoliation was shown to reduce the distinction in survival experience between different types of surfaces, and between surfaces of teeth from children of different socio-economic class or fluoridation status. Clustering of data had little effect on inferences of parameter significance.

Provision of prevention to adults in NHS dental practices and attitudes to prevention.

AIMS: To identify the number of claims reported by the Dental Practice Board (DPB) for the three adult preventive codes for the year ending October 2002 in Wales. To identify the attitudes of practitioners to the use of these codes. DESIGN: A cross-sectional study using routinely gathered DPB data and data generated by a postal questionnaire. SAMPLE: All DPB claims for the 12 months ending October 2002. A randomised sample of 400 dentists currently practising in Wales for the postal questionnaire. RESULTS: The DPB data showed great variation across Wales for: the number, type and distribution of preventive code claims; the age and payment status of patients prescribed these treatments; and the proportion of male versus female dentists claiming for the codes. The questionnaire response rate was 67% (n = 267). The results showed that most respondents were deterred by the restrictions on the codes, insufficient reimbursement and a perceived unwillingness of patients to pay for preventive care. CONCLUSION: Few dentists provide preventive care to adults under the existing remuneration system. Work is necessary to enable dentists to use effective preventive techniques for adult patients. These results can be considered to show the baseline provision of prevention and could facilitate the evaluation of any changes to the current system.

Sedation in Wales: a questionnaire.

AIM: To identify the current provision of sedation in primary dental care in Wales. DESIGN: Postal questionnaire survey. SETTING: Wales 2003. SUBJECTS AND MATERIALS: Questionnaires were sent to all dentists appearing on the Dentists Register with addresses in Wales (n = 1374). The questionnaires sought details on personal status, use of and training in conscious sedation techniques. RESULTS: In total 951 (69%) questionnaires were returned, 720 (90%) respondents worked in a primary dental care setting. Only 87 (12.1%) primary care dentists offered some form of sedation. CONCLUSIONS: The provision of conscious sedation services in primary dental care in Wales is poor.

Organ donation after circulatory death in a university teaching hospital.

Although organ transplantation is well established for end-stage organ failure, many patients die on waiting lists due to insufficient donor numbers. Recently, there has been renewed interest in donation after circulatory death (DCD). In a retrospective observational study we reviewed the screening of patients considered for DCD between March 2007 and December 2012 in our hospital. Overall, 148 patients were screened, 17 of whom were transferred from other hospitals. Ninety-three patients were excluded (53 immediately and 40 after review by donation staff). The 55 DCD patients were younger than those excluded (P=0.007) and they died from hypoxic brain injury (43.6%), intraparenchymal haemorrhage (21.8%) and subarachnoid haemorrhage (14.5%). Antemortem heparin administration and bronchoscopy occurred in 50/53 (94.3%) and 22/55 (40%) of cases, respectively. Forty-eight patients died within 90 minutes and proceeded to donation surgery. Associations with not dying in 90 minutes included spontaneous ventilation mode (P=0.022), absence of noradrenaline infusion (P=0.051) and higher PaO2:FiO2 ratio (P=0.052). The number of brain dead donors did not decrease over the study period. The time interval between admission and death was longer for DCD than for the 45 brain dead donors (5 [3-11] versus 2 [2-3] days; P<0.001), and 95 additional patients received organ transplants due to DCD. Introducing a DCD program can increase potential organ donors without reducing brain dead donors. Antemortem investigations appear to be acceptable to relatives when included in the consent process.

The orthodontic condition of children in England, Wales and Northern Ireland 2013.

Background The 2013 Children's Dental Health Survey is the fifth in a series of national surveys.Aims This paper reports the orthodontic condition of 12- and 15-year-olds and how they and their parents feel about the appearance of their teeth.Methodology A representative sample of children (5y, 8y, 12y, 15y) in England, Wales and Northern Ireland were invited to participate in dental examinations. A modified Index of Orthodontic Treatment Need (IOTN) was used as a measure of orthodontic treatment need for 12- and 15-year-olds. Children and parents were invited to complete a questionnaire about oral health behaviour and attitudes.Results Nine percent of 12-year-olds and 18% of 15-year-olds were undergoing orthodontic treatment at the time of the survey. Forty-four percent of 12-year-olds and 29% of 15-year-olds expressed a desire for straighter teeth, however over half of this group would not qualify for NHS treatment. Unmet treatment need was higher in children eligible for free school meals (P <0.05 at 15y).Conclusions Provision of and demand for orthodontic treatment is increasing, with a significant proportion of children who desire orthodontic care not eligible to receive it. Children from deprived backgrounds have greater unmet orthodontic treatment need.

Relationship of caries with socioeconomic status in 14-year-old children from communities with different fluoride histories.

The aim of this study was to describe the caries prevalence of 14-yr-old children living in two fluoridated communities, a non-fluoridated community, and a community that discontinued fluoridation 5 yr before the children were examined and to relate the caries prevalence to socio-economic status. Clinical examinations were completed on 413 children of whom 227 had been continuously resident in their towns. Children living in the fluoridated communities had significantly lower mean DMFT and DMFS scores than those in the non-fluoridated town. The children from the town that had discontinued fluoridation 5 yr earlier had mean DMFT and DMFS scores that occupied an intermediate position. The differences were greater when only the continuous residents were examined. There were significant differences in the mean DMFT and DMFS when comparing socioeconomic status and fluoridation of the water supply. No interaction effect was demonstrated between these two factors.

An investigation of the disposal of hazardous wastes from New Zealand dental practices.

A national survey was conducted to investigate current procedures in New Zealand dental practices for disposal of clinical waste. A questionnaire was sent out to all dental practices in New Zealand, and non-returns were followed up by two further mailings. From three mailings 767 useable questionnaires were returned (71.3% of those sent out, 79.0% of those potentially valid). Responses indicated that 56.4% of dental practices disposed of bloody swabs into the waste paper bin, and 24.4% disposed of contaminated sharp items into the general household refuse collection. Qualitative interviews with dental practitioners revealed a lack of concern about disposal of contaminated waste into the general waste. The existence of legislation governing waste disposal was not sufficient to motivate many practitioners to comply with guidelines. In some areas there was no specialised waste disposal service available, but some dentists had rejected a specialised service on the grounds of cost or inconvenience. Substantial efforts were made to salvage amalgam waste to be sold for scrap.

Oral health promotion evaluation--time for development.

Increasing emphasis is now being placed upon the evaluation of health service interventions to demonstrate their effects. A series of effectiveness reviews of the oral health education and promotion literature has demonstrated that many of these interventions are poorly and inadequately evaluated. It is therefore difficult to determine the effectiveness of many interventions. Based upon developments from the field of health promotion research this paper explores options for improving the quality of oral health promotion evaluation. It is essential that the methods and measures used in the evaluation of oral health promotion are appropriate to the intervention. For many oral health promotion interventions clinical measures and methods of evaluation may not be appropriate. This paper outlines an evaluation framework which can be used to assess the range of effects of oral health promotion programmes. Improving the quality of oral health promotion evaluation is a shared responsibility between researchers and those involved in the provision of programmes. The provision of adequate resources and training are essential requirements for this to be successfully achieved.

Challenges with studies investigating longevity of dental restorations--a critique of a systematic review.

OBJECTIVES: A systematic review is a method of evaluating the published and unpublished literature relating to a specific area or topic. The objectives of this paper are to identify and discuss problems encountered in synthesising the available literature; and to make recommendations for the future conduct and reporting of clinical trials that aim to determine the longevity of dental restorations. DATA SOURCES: Studies were identified by a wide search of published and unpublished material in any language using a large number of general and specialist data bases, hand searching of key dental journals and searching of abstracts from conference proceedings. STUDY SELECTION: Pre-defined inclusion criteria based on objective outcome measures of restoration longevity and study designs were applied to determine study selection. CONCLUSIONS: A review of the longevity of dental restorations completed recently encountered substantial problems in designing an appropriate protocol to address this issue. The review found that many of the factors reported previously as affecting restoration longevity could not be confirmed using the agreed systematic review protocol that incorporated an objective study design. Further, the multiplicity of study designs, and reporting methods found in the literature made meta-analyses impossible. A proforma is proposed in order to aid the design of future research into the longevity of restorations.

Incidence of facial fractures resulting in hospitalisation in New Zealand from 1979 to 1988.

The incidence and aetiology of facial fractures resulting in admission to public hospitals in New Zealand in 1987 were investigated retrospectively from data collected by the Health Statistical Services. Data were analysed by the age group, ethnic origin and gender of those affected. During 1987 the overall incidence of facial fractures was 47.9/100,000 of the population. The highest incidence was for Maori males at 152/100,000. A comparison with data for the period 1979 to 1988 showed a decrease for the population as a whole but an increase for those who declared themselves to be Maori. Assault was the most common cause of facial fractures resulting in hospitalisation for both males and females. Sport was the second most common cause of facial fractures with rugby football contributing two-thirds of these. These results indicate where future preventive measures should be targeted.

Comparison of four composite deprivation indices and two census variables in predicting dental caries in 12-year-old children in Wales.

OBJECTIVE: To compare the explanatory power of four composite indices of social economic status in their ability to predict dental caries experience. BASIC RESEARCH DESIGN: A secondary analysis of Welsh BASCD survey data using ward aggregated dental data, census variables and composite measures of deprivation. CLINICAL SETTING: Examinations took place in schools. PARTICIPANTS: All 12-year-old children examined in the 1996/97 survey. MAIN OUTCOME MEASURES: The explanatory variables were Jarman index, Welsh Underprivileged Area score (WUPA), Carstairs and Townsend indices and the outcome measure was mean DMFT. RESULTS: The amount of the mean DMFT explained by the explanatory variables ranged from 62.9% with Welsh Underprivileged Area score (WUPA) in Bro Taf Health Authority to 4.2% with the Jarman index in Dyfed-Powys health authority. Of the constituent parts of the composite variables only the percentage with no car appeared in the 'top three' variables in all but one of six models. CONCLUSIONS: The composite indices explained very different amounts of the variation in mean DMFT between the different health authorities. It would be unwise to rely on any one as a method of predicting which sections of the population would be likely to have dental disease.

Oral health systems in Europe. Part II: The dental workforce.

OBJECTIVE: To describe and compare the practice of dentistry and the dental workforce in eighteen European countries. BASIC RESEARCH DESIGN: Semi-structured, in-depth validation interviews were carried out with key-informants from the main national dental associations of EU and associated countries. The interviews were structured around the responses to a previously completed questionnaire, whose topics and terminology had been agreed in advance with the collaborating associations. The resulting descriptions of dental practice and the dental workforce in each country were returned for further validation and correction by the collaborating associations. Ultimate editorial control over the review of each country's oral health system rested with the academic unit from which the associations jointly commissioned the study. RESULTS AND CONCLUSIONS: With the exception of Austria the primary training and registration of dentists is now more or less standard across Europe. However, wide international variation exists in the official recognition of dental specialists and auxiliaries. The Nordic countries of Sweden, Finland and Iceland recognise the broadest range of specialties. In contrast Spain, Portugal, Luxembourg and Belgium currently do not formally recognise any types of specialist practice. Fee-for-service is the dominant form of remuneration for dentists across Europe, but considerable variation exists in the level of fees, how they are decided and the proportion paid by the patient. When based upon standard questionnaires, semi-structured interviews with key informants are an effective method for capturing both the specifics of how an oral health system works, and the general similarities and differences between countries.

Oral health systems in Europe. Part I: Finance and entitlement to care.

OBJECTIVE: To describe and compare the oral health systems in 18 European countries. BASIC RESEARCH DESIGN: Semi-structured, in-depth validation interviews were carried out with key informants from the main national dental associations of EU and associated countries. The interviews were structured around the responses to a previously completed questionnaire, the topics and terminology of which had been agreed in advance with the collaborating associations. The resulting descriptions of dental practice and the dental workforce in each country were returned for further validation and correction by the collaborating associations. Ultimate editorial control over the review of each country's oral health system rested with the authors. RESULTS AND CONCLUSIONS: Oral health care is mainly financed by government-regulated or compulsory social insurance in seven of the 18 countries examined here: Austria, Belgium, France, Germany, Luxembourg, The Netherlands and Switzerland. Providing universal or near-universal coverage by membership of insurance institutions, these systems provide oral health care for about 180 million people across Europe, and almost half of all EU citizens. In the Nordic countries and the UK entitlement to care is typically based upon residence or citizenship, and apart from in Norway and Iceland is provided within a tax-funded and government-organised health service. In southern Europe, Norway, Ireland and Iceland oral health care is largely financed directly by the patient, with occasional support through private insurance. Some publicly-funded and organised services do exist in these countries but generally only for specific population groups (e.g. children, unemployed), or in particular regions.

Changing trends in South Wales fluoride prescription dispensing (1993-7).

OBJECTIVE: To observe patterns of fluoride preparation dispensing by primary care practitioners in a health authority. DESIGN: Observational study. SETTING: The Prescription Pricing Agency of the Welsh Health Common Services Authority (WHCSA). SUBJECTS: Individuals who had exchanged a prescription for a fluoride preparation at a pharmacy in Bro Taf Health Authority in the six months from 1 January 1997 to 30 June 1997. METHOD: Information from each prescription including a fluoride preparation, passed to WHCSA from pharmacists during the study, was entered onto a database, including the prescriber's postcode and profession, the recipient's postcode and product information. Numbers of dental prescriptions were correlated to local levels of NHS primary dental care provision and caries prevalence data. Comparisons were made with a similar study undertaken in 1993. RESULTS: 415 dentists' prescriptions were dispensed within the area, of which 38.8% originated from five dentists. At least one prescription had been made by 89 of the 253 local primary dental care providers (35%). Within the area monitored in both 1993 and 1997, dental prescribing rates had almost halved. Of the 122 doctors' prescriptions that were dispensed over the six-month period, 98 were mouthwash preparations for adult patients and four were for children. CONCLUSION: NHS provision of fluoride supplementation was low and remained related to prescribing patterns of individuals rather than to evidence on local variations in dental caries prevalence.

Increases in cavity volume associated with the removal of class 2 amalgam and composite restorations.

Removal of amalgam restorations from class 2 cavities has been shown to cause increases in cavity volume. The aim of this study was to test whether the removal of composite resin from class 2 cavities was associated with greater increases in cavity volume compared to that produced during removal of amalgam. Class 2 cavities were prepared in previously extracted human molar teeth and the cavity volumes calculated. The teeth were restored with either amalgam or a composite resin and appropriate dentin bonding agent (APH/Optibond). Two dentists removed the restorations, and the resultant cavity volumes were calculated. The results were analyzed using a standard t-test, ANOVA, and a Scheffe F-test. Removal of composite from class 2 cavities resulted in significantly increased cavity volumes compared to that when amalgam was removed. While there was significant interoperator difference in cavity volumes following removal of amalgam from class 2 cavities, there was no significant interoperator difference in cavity volumes following the removal of composite. These differences were related to the methods used to eliminate the restorations from the cavities.

Survey of infection control procedures in New Zealand dental practices.

A national survey was conducted to investigate current procedures in New Zealand dental practices for control of cross-infection, and to gauge dentists' perceptions of their current procedures. A questionnaire was sent to all dental practices in New Zealand, and non-returns were followed up by two further mailings. From three mailings 767 useable questionnaires were returned (71.3 per cent of those sent out, 79.0 per cent of those potentially valid). Responses indicated that formal guidelines were generally well received, but varying proportions thought that some recommendations were unrealistic or irrelevant. Asked whether the dental practice offered treatment to 'high risk' (HIV-positive or HBAg-positive) patients, 25.3 per cent responded that none sought treatment. Almost all practices (92.0 per cent) had an autoclave, but only 42.8 per cent of practices autoclaved dental handpieces, and 10.9 per cent of practices wiped, cold disinfected or boiled extraction forceps. The large majority of responses complied with guidelines, but specific difficulties were identified with regard to sterilisation of handpieces.

An investigation of the disposal of dental clinical waste in Bangkok.

This study investigated the disposal of clinical waste within dental surgeries in Bangkok, Thailand and followed the waste trail to the rubbish tips. A questionnaire was sent to all dental practices in the Bangkok Metropolitan Area. The response rate was 57.7 per cent. At the same time, rubbish collectors and scavengers were interviewed to see if they encountered clinical dental waste. Few dentists complied with all recommendations for the disposal of waste. Most waste was disposed of into the domestic rubbish stream. Rubbish collectors and scavengers knew what dental rubbish looked like and some had had needle-stick injuries. Although recommendations can be made to the dental profession to alter their behaviour, real improvement is unlikely without changes to legislation and social policy.

Dentistry and the National Health Service in the context of Europe.

Many British dentists consider that because of the NHS, oral healthcare provision in Europe is more comprehensive, less controlled and more remunerative than the UK, a view that is often shared by their European colleagues. In this article, the oral healthcare systems of most European countries are classified and compared, and some strengths, similarities and weaknesses are identified and discussed.

The EU manual of dental practice--a guide for dentists planning to practice abroad.

How does a dentist go about moving practice to another EU country? This article describes a new publication which aims to explain the dental practice arrangements in a number of European countries and clear up the EU red tape.