Identification of yeast in chronic wounds using new pathogen-detection technologies.

OBJECTIVE: To evaluate the ability of two new diagnostic methods to detect and accurately identify yeast associated with chronic wound infections. METHOD: Fungal tag-encoded FLX amplicon pyrosequencing (fTEFAP), a universal fungal identification method, bacterial tag-encoded FLX amplicon pyrosequencing (bTEFAP), a universal bacterial identification method, and a new quantitative polymerase chain reaction (qPCR) wound pathogen panel were used to evaluate three chronic wounds suspected to contain yeast. RESULTS: Forty wound samples were analysed in addition to the three samples suspected of containing yeast. The qPCR panel, which targets Candida albicans, detected this yeast in two of the three wound samples. In contrast, fTEFAP detected yeast in each of the three samples: two showed Candida albicans and the third Candida parapsilosis. fTEFAP also identified a lower level of Candida tropicalis in one of the wounds that was positive for Candida albicans. The qPCR wound panel results were returned within two hours, while the fTEFAP results were returned within 24 hours. CONCLUSION: Two new molecular methods have been developed to aid wound pathogen diagnostics. The quantitative PCR wound panel is rapid but is limited to major wound-associated bacteria and yeasts. The universal fTEFAP and bTEFAP methods take 24 hours to return results but are able to detect the relative contribution of any bacteria of yeast in a chronic wound diagnostic sample. DECLARATION OF INTEREST: Southwest Regional Wound Care Center is a clinical wound-care provider seeking to improve the ability of wound care practitioners to help patients. The Research and Testing Laboratory develops molecular methods including fTEFAP, bTEFAP and the quantitative PCR wound panel.

Public policy and the market for dental services.

Social inequality in access to oral health care is a feature of countries with predominantly privately funded markets for dental services. Private markets for health care have inherent inefficiencies whereby sick and poor people have restricted access compared to their healthy and more affluent compatriots. In the future, access to dental care may worsen as trends in demography, disease and development come to bear on national oral healthcare systems. However, increasing public subsidies for the poor may not increase their access unless availability issues are resolved. Further, increasing public funding runs counter to policies that feature less government involvement in the economy, tax policy on private insurance premiums, tax reductions and, in some instances, free-trade agreements. We discuss these issues and provide international examples to illustrate the consequences of the differing public policies in oral health care. Subsidization of the poor by inclusion of dental care in social health insurance models appears to offer the most potential for equitable access. We further suggest that nations need to develop national systems capable of the surveillance of disease and human resources, and of the monitoring of appropriateness and efficiency of their oral healthcare delivery systems.

Prevalence of early childhood caries among First Nations children, District of Manitoulin, Ontario.

BACKGROUND: Epidemiological studies of Aboriginal communities in Canada and Native American populations in the United States have reported that early childhood caries (ECC) is highly prevalent. The purpose of this study was to determine the prevalence of ECC and dental caries in the First Nations population of 3- and 5-year-old children in the District of Manitoulin, Ontario to assist in developing effective dental health promotion strategies. METHODS: All 3- and 5-year-old children in elementary schools and day-care centres in seven First Nation communities were eligible for the survey examination. Three-year-old children at home and 5-year-old children attending school off-reserve in six of the communities were also eligible for epidemiological survey examination of oral health status including caries, gingival and soft tissue conditions. Cases of ECC were defined as children with caries or restorations on two or more primary maxillary incisors or canines or those having a total decayed, missing, filled primary teeth (dmft) score of 4 or greater. RESULTS: A total of 87 children (59% 5 years old, 54% females) were examined. Seventy-four per cent of children had one or more carious lesions. Forty-five cases of ECC were found, a prevalence of 52%. The mean dmft score for cases was 7.5 (95% CI 6.5-8.4) and 0.8 (95% CI 0.5-1.1) for non-cases (P < 0.001). Boys in both age groups were more likely to be affected by ECC than girls. CONCLUSION: Our results indicate that dental caries and ECC are highly prevalent in this population, with ECC cases having 6.7 more dmft than non-cases.

Observer agreement in the grading of oral epithelial dysplasia.

OBJECTIVES: To determine the extent of observer agreement in diagnosis of oral epithelial dysplasia (OED). Published studies of OED examiner agreement report relatively low agreement levels; however, these studies were limited by the methodologies employed. METHODS: For this study, 64 slides were each independently examined twice by three oral pathologists. Consistency was assessed by determining intra- and interexaminer agreement. Conformity was assessed by using the modal diagnosis as a gold standard. RESULTS: The group showed moderate interobserver agreement when grading the presence or absence of OED with a group-simple kappa (Ks) of 0.51 (95% CI = 0.42-0.61), and substantial agreement when using a 5-point ordinal scale with a group-weighted kappa (Kw) of 0.74 (95% CI = 0.64-0.85). The group showed fair to substantial intraexaminer agreement when assessing the presence or absence of OED, with Ks ranging from 0.22 to 0.78, and showing almost a perfect agreement using a 5-point ordinal scale, with Kw ranging from 0.82-0.96. Conformity with the comparison standard modal diagnosis was almost perfect, with pairwise Kw ranging from 0.81 to 0.92. CONCLUSION: Overall, there was substantial intra- and interobserver consistency and almost perfect conformity in the grading of OED. Appropriate statistical methods are necessary to determine the degree of observer agreement.

The U.S. Surgeon General's report on oral health in America: A Canadian perspective.

This paper provides an overview of last year's U.S. Surgeon General's report on oral health, describes the burden of oral diseases and craniofacial disorders in the United States, and draws parallels with the state of dental health in Canada and in the province of Ontario. It concludes by focusing on the report's recommendations for future action and briefly notes some of the lessons that Canadians can learn from these findings. The goal of this paper is to stimulate further discussion of the issues raised in the report, in an effort to encourage public-private partnerships dedicated to the creation and support of programs to make oral health a more integral component of general health.

Clinical decision-making for caries management in root surfaces.

This report presents the results of an evidence-based approach to obtaining the best available information on the natural history, prevalence, incidence, diagnosis, and treatment of root caries. Searches of electronic databases produced 807 references; from these and from citations in the selected articles, a final 161 references were used. We found that the information on the natural history of the disease does not provide practitioners with probabilities of, or time estimates for, progression of the disease through stages. For patients aged thirty and older, the prevalence of root caries is roughly 20 to 22 percent less than a person's age. Severity reaches over one lesion by age fifty, two lesions by age seventy, and just over three lesions for those seventy-five and older. About 8 percent (odds of 1:11) of the population would be expected to acquire one or more new root caries lesions in one year. The accuracy of current systems of diagnosis is unknown, although color has been shown to have little validity. Using the criteria of "softness" to define active lesions has been validated by the presence of microbes in the lesion. One strong study and other studies with weaker design or shorter duration add consistent support for the use of fluorides in the remineralization of root caries. Every three-month application of chlorhexidine varnish was shown to be efficacious in one arm of one study. Evidence for restoration of root caries is tentative since the studies were of limited design and duration.

The history of dental programs for older adults.

Compared with other age groups, the elderly have less access to oral health care services and poorer oral health status. Most provinces have no publicly funded programs to address these inequities and the volunteer efforts of professionals and hospital-based programs have had little effect. In Ontario, two expert committees have called for seniors' programs augmented by a strong outreach component to be delivered by public health services. Their recommendations have not been implemented and, worse, some public health programs have lost the capacity to maintain the preventive services they once provided. The development of public policy to address the needs of the elderly is thwarted by the narrow definition of public health problems, the reluctance of the dental profession to lobby for public funding, the bias toward investment in younger groups, and the persistence of a "reverse public funding program" whereby the employed, more affluent receive dental care as a tax-free benefit and the retired, lower-income elderly pay in after-tax dollars.

Comparing characteristics of Canadians who visited dentists and physicians during 1993/94: a secondary analysis.

Unlike medical care, dental services are not included in Canada's universal system of health care. Using the data from the 1994 National Population Health Survey, we estimate the proportion of the population aged 12 and older visiting dentists and physicians in 1993/94 and compare the factors that influence the use of dentists' and physicians' services. Overall, 52.4% of Canadians made one or more visits to a dentist and 78.4% visited a physician. Logistic regression analysis indicates that whereas visiting a family physician is more likely to occur for people who are ill (generally, on medications or needing help with daily living) or pregnant, visiting a dentist is more likely to occur for young, healthy, wealthy and highly educated people. Future dental health policy needs better information on health status linked to use of services.

A system of diagnostic codes for dental health care.

OBJECTIVES: We set out to develop and implement a system of diagnostic codes for use in the computerized management information system of the Community Dental Services of the North York Public Health Department. METHODS: We received staff input on common diagnoses, reviewed other diagnostic systems and established criteria for an ideal coding system. The codes are consistent with the format of other classification systems used in dental management information in Canada. They were implemented in 1997-98. RESULTS: We developed a system of four-digit, numeric codes for dental diagnoses. The diagnostic codes are specific at the level of the patient, consistent with current evidence on the natural history and classification of diseases, consistent with conventional measures of oral conditions, and fit the paradigm of the Canadian system of treatment codes. In the first year, 91 percent of 6,740 patients had at least one diagnosis, with a mean of 2.5 per patient. The five most common diagnoses were smooth surface caries, pit and fissure caries, calculus, teeth with deep fissures, and gingivitis. CONCLUSIONS: We have developed a coding system for dental diagnoses that has achieved high use and provided more accessible information on the conditions seen by staff dentists.

Preventive health care, 1999 update: prevention of oral cancer mortality. The Canadian Task Force on Preventive Health Care.

BACKGROUND: Approximately 3,000 new cases of oral cancer are diagnosed each year in Canada. Most of these cases occur among older adults with a history of tobacco use or excessive alcohol consumption. Preventive interventions for oral cancer include counselling of patients to modify risk factors and screening to identify precancerous and early-stage lesions. This report presents evidence-based guidelines on the prevention of oral cancer and precancer among asymptomatic patients. METHODS: Literature searches of the 1966-1999 MEDLINE and CANCERLIT databases were completed using the major MeSH heading mouth neoplasms. References from articles and recommendations of organizations were also reviewed. The evidence-based methods of the Canadian Task Force on Preventive Health Care were used to assess evidence and to develop guidelines. Advice from experts and other recommendations were taken into consideration. RESULTS: In cohort and case-control studies, smoking cessation decreased the risk of oral cancer and precancer. Randomized controlled trials (RCTs) indicate counselling by trained health care professionals is effective in promoting smoking cessation. Although counselling has been effective for the reduction of excessive alcohol consumption in RCTs, no studies have examined whether alcohol reduction reduces the risk of oral cancer or precancer. The usefulness of general population screening is limited by the low prevalence and incidence of the disease, the potential for false-positive diagnoses and the poor compliance with screening and referral. There is no evidence that screening of the general population or high-risk groups leads to a reduction in mortality or morbidity from oral cancer. INTERPRETATION: There is good evidence to specifically consider smoking cessation counselling in a periodic health examination (grade A recommendation). For population screening, there is fair evidence to specifically exclude screening for oral cancer (grade D recommendation). For opportunistic screening during periodic examinations, there is insufficient evidence to recommend inclusion or exclusion of screening for oral cancer (grade C recommendation). For patients at high risk, annual examination by physician or dentist should be considered. Risk factors include tobacco use and excessive consumption of alcohol. These recommendations are similar to those made by the Canadian Task Force on the Periodic Health Examination in 1994 and by the U.S. Preventive Services Task Force in 1996.

A comparison of certain practice characteristics of dental anesthesiologists in Canada and the United States.

An existing database was used to compare aspects of dental anesthesiology practice of dental anesthesiologists in Canada (n = 32) and the United States (n = 123). Data focusing on percutaneous injuries were obtained through a mailed questionnaire that was returned anonymously. Respondents provided information on the treatment of patients under deep sedation or general anesthesia only. Eighty-one percent of Canadians and 61% of Americans returned the questionnaire. The vast majority (84%) of injuries reported were due to sharps associated with general dentistry compared with those associated with anesthesiology. Canadians were more likely to be operator-anesthetists (P < .01) and to experience a percutaneous injury (P < .01) than US practitioners. American practitioners were more likely to have a greater proportion of the caseload under the age of 20 (P < .02). No other significant differences were observed. These results illustrate a number of unique attributes of the practice of dental anesthesiology in these 2 countries.

The occupational risk to dental anesthesiologists of acquiring 3 bloodborne pathogens.

OBJECTIVE: To estimate the occupational risk to dental anesthesiologists of contracting 3 bloodborne pathogens: hepatitis B (HBV), hepatitis C (HCV), and human immunodeficiency virus (HIV). METHODS: Through an anonymously returned, mailed questionnaire, dental anesthesiologists in Canada and the United States provided information regarding percutaneous and mucocutaneous contacts with contaminated fluid during the treatment of patients under deep sedation and general anesthesia as well as other general practice information. A mathematical model was applied to determine the occupational risk. RESULTS: Of the 101 (65%) returned questionnaires, 98 reported having treated patients within the previous 6 months. Of these, 41 (42%) had at least one percutaneous accident (89 accidents in total), and the projected mean annual injury rate for dental anesthesiologists overall was 1.82. The most common causes of injury were burs, intraoral needles, and dental instruments. Operator error during use was associated with 31% of reported accidents. Significantly more injuries were reported by those who also reported a mucocutaneous contact and by those working more than 25 hours per week. The projected mean annual number of mucocutaneous exposures was 0.88 for dental anesthesiologists overall. CONCLUSIONS: The calculated annual risk to the average dental anesthesiologist of acquiring HBV (if not immune), HCV, and HIV following percutaneous injury was very low for all infections (HBV the most; HIV the least). The risk of contracting HIV following mucocutaneous contact was extremely low.

Reducing variability in treatment decision-making: effectiveness of educating clinicians about uncertainty.

The objective of this study was to investigate whether or not education about the concept of uncertainty reduced variability in treatment decision-making. Three small groups of dentists in North York, Canada were asked to make restorative treatment decisions about simulated bitewing radiographs. They subsequently took part in a seminar about variations in perception and judgement and were given explanations of sensitivity, specificity and receiver operating characteristic (ROC) curve analysis. A repeat reading of the radiographs was then performed by both test and control groups. Results indicated that the intervention increased the accuracy, and decreased the variability of dentists' restorative treatment decisions. Kappa statistics were 0.33, 0.34 and 0.31 before the seminar, and 0.40, 0.43 and 0.41 after the seminar. Standard errors for kappas were 0.06, 0.05 and 0.05 before the seminar, and 0.02, 0.02 and 0.05 after the seminar. The area under the ROC curve was 0.7136 before the seminar and 0.7835 after the seminar. The data demonstrate that the dentists' decisions were less variable and more accurate following the educative intervention. This study suggests that there is potential for improving consistency and accuracy in clinical decision-making through education in probabilistic reasoning.

Managing dental care versus managed dental care: looking south from north of the 49th parallel.

In the United States, aggregate expenditures on the largely private health care system, as a proportion of Gross National Product, exceed those of all other countries. Under private enterprise, the health care system in the United States grew as predicted by the underlying equation that more service volume equates to more revenue for hospitals and providers. Managed care is the response of for-profit health care organizations to meet the demands of U.S. corporations to contain the escalating costs of hospital, medical and other health care benefits for their employees. Managed health care has several models, but preferred provider organizations (PPOs) have been the model that has increased most rapidly. In contrast, managers of Canadian public dental programs plan, organize, direct and control more of the structures, processes and outputs to achieve desired outcomes for special groups. In Canada, the approaches to quality assurance, restraint of trade and the power of the professional lobby are different from the approaches in the United States. Nonetheless, the context of private dental care plans is very similar to the context that produced managed health care in the United States. Better management to meet demonstrated needs with evidence-based care can result in sustainable, adequately financed plans and avoid the deep-discount form of managed dental care.

Developing evidence-based programme guidelines for children's dental care in a dental public health unit in Ontario, Canada.

The North York Public Health Department operates a school-based dental care programme. Dental care providers are expected to follow guidelines in order that the programme shall achieve the best outcomes for the clients served. A model is described by which published evidence informs the guideline development process. The process is considered to require knowledge of the epidemiology of dental disease in the target population; skills in collecting, critically appraising and summarising the scientific literature; working with internal and external advisory panels to write the guidelines; disseminating results and assessing both compliance and health outcomes. This work is one example of a larger trend to evidence-based health care.

The use of dental radiographs to estimate the probability of cavitation of carious interproximal lesions. Part I: Evidence from the literature.

It is generally recommended that a cavitated, carious lesion be present before an interproximal tooth surface is restored. These lesions often are not clinically visible, however, and must be diagnosed using dental radiographs. Radiographic results can underestimate and overestimate the size of a carious lesion. The purpose of this study was to review and graphically summarize studies that have investigated the relationship between the radiographic image and the presence of a cavitated lesion on the interproximal surfaces of permanent teeth. A search of the literature identified 13 studies, eight of which were suitable for inclusion in our summary. Using the positive and negative likelihood ratios from each study, a graphical summary was developed showing the probability of cavitation based on the radiographic test result and the dentist's pre-radiograph estimate of the probability of cavitation. This graph should allow dentists to more accurately inform their patients of the probability of a cavitated interproximal lesion being present or absent. As a further observation, our findings suggest that to avoid frequent false positive diagnoses, dentists should estimate the probability of cavitation to be at least 30 per cent before they prescribe radiographs for patients who visit them on a regular basis.

The use of dental radiographs to estimate the probability of cavitation of carious interproximal lesions. Part II: Two patient scenarios.

Diagnosis of a cavitated interproximal lesion is often not confirmed until the tooth is treated. Before treatment, clinicaians and patients are dealing with probabilities which can be estimated from clinical evidence, radiographic evidence, and information found in the dental literature. The probability of a diagnostic test result being correct is affected by the threshold of the test and the pretest probability of the disease in question, which varies with the prevalence of the disease. We illustrate how clinicians can inform themselves and their patients of the probability of a radiographic lesion being truly cavitated based on graphs that summarize the currently available evidence. Dentists who use these graphs can more accurately inform their patients who can then choose the course of care that best meets their individual needs.

Oral health and family characteristics of children attending private or public dental clinics.

The City of North York Public Health Department (NYPHD) operates a school-based dental programme that provides preventive and treatment services to children according to evidence-based practice guidelines. This programme and private dental practices (PDP) represent the only sources of dental care for children in North York. The purpose of our study was to compare the oral health and family characteristics of clients from the NYPHD and PDP using a dental examination and a parent interview. Results showed that NYPHD and PDP clients had similar levels of fluorosis, calculus, and periodontal health, but NYPHD clients had experienced greater levels of decay. Clients of the NYPHD and PDP also had significantly different family characteristics, many of which were significantly associated with the presence of one or more decayed primary or permanent teeth. Multivariate logistic regression identified mother's immigration history, past caries experience, and parents' rationale for scheduling their child's dental appointments as the principle risk makers for dental decay. When compared with PDP clients, the NYPHD serves higher-needs children who otherwise might not receive care.