Prevalence and trends in periodontitis in the USA: the [corrected] NHANES, 1988 to 2000.

Trends in periodontal diseases in the USA have been documented for years. However, the results have been mixed, mostly due to different periodontal assessment protocols. This study examined change in the prevalence of periodontitis between the NHANES III and the NHANES 1999-2000, and differences in the prevalence of periodontitis among racial/ethnic groups in the USA. Analysis was limited to non-Hispanic black, non-Hispanic white, and Mexican-American adults aged 18+ yrs in the NHANES III (n=12,088) or the NHANES 1999-2000 (n=3214). The prevalences of periodontitis for the NHANES III and the NHANES 1999-2000 were 7.3% and 4.2%, respectively. In multivariable analyses, blacks were 1.88 times (95%CI: 1.42, 2.50) more likely to have periodontitis than whites surveyed in the NHANES III. However, the odds of periodontitis for blacks and Mexican-Americans did not differ from those for whites surveyed in the NHANES 1999-2000. Our findings indicate that the prevalence of periodontitis has decreased between the NHANES III and the NHANES 1999-2000 for all racial/ethnic groups in the USA.

Prevention policies in the light of the changed distribution of dental caries.

Changes in the distribution of caries in economically developed nations over the last 15-20 years include 1) an overall decline in prevalence and severity in child populations; 2) an increasingly skewed distribution, with most disease now found in a small number of children; and 3) concentration of caries in pit and fissure lesions. Exposure to fluoride is usually seen as the principal reason for the caries decline, with little change in intraoral levels of cariogenic organisms or the annual consumption of sugars. Prevention activities are still most often conducted under policies that were established at a time when caries was a more widespread public health problem, so these policies should be critically examined in the light of modern conditions. While prevention should remain the prime activity of public health agencies, despite the reduced severity of caries, the relative economic efficiency of various procedures should be constantly evaluated. Despite the attractions of targeting, cost-effective prevention should be aimed first at the whole population, with more expensive activities targeted to all children in a chosen geographic area rather than to individually selected children. In the Scandinavian countries the prime population strategies are the regular use of fluoride toothpaste and public education that emphasizes oral hygiene. In selected areas where caries levels are still relatively high (that is, targeted geographic areas), fluoride rinse and tablet programs, provided for a whole classroom at a time, can enhance intraoral fluoride levels where necessary. Fluoride varnish and sealants, though effective, are expensive and need careful selection of locality and teeth to be efficient. Individual children with a persistent caries problem, now relatively small in number, can receive individualized preventive treatment in the clinics of the school dental service.

How useful are cross-sectional data from surveys of dental caries?

Surveys are projects involving systematic data collection without a specific hypothesis to be tested and hence without a specific research design. This paper reviews their uses, and some of the issues involved with measuring dental caries in surveys. The principal benefits of surveys are in (a) monitoring trends in oral disease when the surveys are repeated periodically: and (b) giving dental health a visibility it might otherwise not get among policy-makers. On the other hand, they are of limited use in determining treatment needs for a population, evaluating treatment outcomes, and evaluating prevention programs. Some major issues in caries surveys today include difficulties with the DMF index; the use of exclusively visual versus visual-tactile criteria; "hidden" caries; and the appropriate role for early, non-cavitated carious lesions. The DMF index suffers from its mixing of disease and treatment, and more research is needed to determine the most appropriate role for exclusively visual criteria in surveys. Trade-offs, such as weighing the benefits of exclusively visual criteria against the probable greater difficulty in finding "hidden" caries, have not been determined. Inclusion of non-cavitated lesions in a survey will increase its cost. Organizers should therefore be clear before the survey on how this additional information will be used to justify the additional expense.

A retrospective analysis of the cost-effectiveness of dental sealants in a children's health center.

A retrospective patient record analysis was conducted to study the cost-effectiveness of dental sealants placed under routine, unrestricted practice condition in a fluoridated community. The 26 dentists who provided care at the clinic over the period of the study used their own clinical judgement to determine sealant placement or alternative treatment. Dental services for 275 patients at a children's dental clinic for low-income families were evaluated. All children had at least 3 years between their first and last dental visit (mean = 5.8 years). A lifetable analysis was conducted to compare the probability of survival (restoration-free tooth years) and costs incurred to first molars of children who did not receive sealants, received any sealants, or received sealants on all first molars. Among the children with sealants, comparisons were also made between sealed and unsealed teeth in children who did and did not have a first molar restoration prior to sealant placement. Costs included the costs of sealants and restorative treatments for these teeth over time. Depending on the conditions under which sealants were placed, cost-savings or improving cost-effectiveness with time were found. A strategy of identifying children with prior restorations and sealing the remaining molars showed cost-savings within 4-6 years. For other comparisons, incremental cost-effectiveness ratios became more favorable over time.

An assessment of survival rates and within-patient clustering of failures for endosseous oral implants.

This study examined endosseous cylinder implant survival, defined as the unqualified presence of the implant in the mouth at the end of the observation period, in 598 consecutive VA patients, with a total of 2098 implants. Data were taken from the Department of Veterans Affairs (VA) Dental Implant Registry, which has maintained longitudinal data on the survival of individual dental implants in VA patients since 1987. The maximum time of observation in any one patient was 2040 days (5.6 yr). Survival analysis by use of life-table methods was carried out on both an implant- and a patient-specific basis. Implant cases were accrued randomly, and therefore a random censoring model was used. A correlated binomial model was used for assessment of the degree of within-patient clustering of implant removals. Results showed that the implant-specific survival rate during the longest time interval (5.6 yr) was 89.9%; the patient-specific implant survival rate during the same time was 78.2%. Among implants which were removed, the mean time to removal was 292 days. The hazard function, which describes the probability of implant loss as a function of time, decreased steadily throughout the observation period. The correlated binomial model suggested a clustering of removals within patients with multiple implants (rho = 0.11, p = 0.0001). The odds of having a second implant removed were 1.3 times greater if the patient had already had one implant removed. This study suggests that when implants fail, they do so soon after placement, and the likelihood of failure decreases steadily from implantation through the first five years post-surgery.(ABSTRACT TRUNCATED AT 250 WORDS)

Fluoride exposure in Michigan schoolchildren.

Recent trends in the prevalence of dental caries in children, as well as a possible increase in the prevalence of dental fluorosis, have prompted some researchers to suggest the reassessment of water fluoride concentration standards. Instead of reducing water fluoride concentrations, an alternative approach would be to limit the use of, or reduce the fluoride concentration of, dentifrices, mouthrinses, and supplements. Information about the use of these other sources of fluoride, however, is scarce. Using data from a 1987 survey of Michigan schoolchildren, exposure to selected fluoride sources as well as toothbrushing habits are described. Responses from questionnaires revealed that, overall, 98.5 percent of the children have used fluoride dentifrices, 27 percent have used topical fluoride rinses, 72.5 percent have had at least one exposure to professionally applied topical fluoride, and 27 percent have used dietary fluoride supplements. Although the use of fluoride dietary supplements was appropriate for most children residing in fluoride-deficient Cadillac, the percentages of children in the other communities who have ingested these supplements suggest that these products are being prescribed improperly. Given the almost universal use of fluoride dentifrices at an early age, it may be time to investigate the use of reduced fluoride dentifrices for children. In addition, continuing efforts to decrease inappropriate dietary fluoride supplementation are required.

Patterns of community-based prevention programs.

Prevention of dental caries is most effectively and efficiently achieved by community-based methods, whether in economically developed or developing countries. The role of the private practitioner is a dual one: to support the establishment of appropriate caries-preventive programs such as water fluoridation, salt fluoridation, supervised ingestion of fluoride tablets, and supervised programs of mouthrinsing with fluoride solutions and with such programs in place, to provide personal preventive care to that relatively small number of caries-susceptible people who will still need individual attention. The development of community-based programs is especially critical in those developing countries where the population is growing rapidly and caries is becoming more prevalent, for with their limited resources the only hope of controlling caries is with cost-effective community programs. Control of periodontal disease requires community education, but to be successful it will also require preventive care from practitioners. Even in the economically-developed countries there is a need for greater awareness of periodontal disease among both practitioners and the public. In many of these countries, now that caries is becoming better controlled, the time is ripe for considerably more prevention and treatment of periodontal disease. Its control, in the developing countries, poses special problems, and will have to depend heavily on public education for a considerable time yet. Both community-based programs and private practitioners have important roles to play in the prevention of the most prevalent oral diseases, but these roles need to be carefully defined to avoid wasteful duplication if maximum benefit is to be obtained.(ABSTRACT TRUNCATED AT 250 WORDS)

Fissure sealants: clinical and economic factors.

Existing data on the economics of sealant use are insufficient to permit firm conclusions; an additional handicap is that both data and attitudes are based principally on results with first-generation sealants when it is clear that greatly improved materials are now available. The limited data plus the preceding discussion of issues, however, do allow the following statements by way of conclusions. In public programs, few would argue that the cost-effectiveness of sealants would be enhanced by: (a) Using trained auxiliaries to apply sealant to the fullest extent allowed by law. (b) Applying the most recently developed sealants in which retention rates appear to be most favorable. (c) Their application in areas where proximal caries is low. This means many communities in the United States at present, especially fluoridated areas. Although marginal benefits have not been determined, sealants would appear to complement the use of fluoride. There is less clarity on other areas where some tradeoffs would be required, for the nature of the tradeoffs cannot be specified. These areas include: (d) Whether the program should be based on a single application or whether there should be annual checks and reapplications. Reapplications will push effectiveness closer to 100 percent, but will incur greater costs. The ideal situation would be virtual 100 percent retention of sealant over a long time following a single application, but that outcome is unlikely in a public program. (e) Whether all molars and premolars should be sealed. There is general agreement that first and second molars should be sealed as soon as possible after eruption because of their susceptibility to occlusal caries.(ABSTRACT TRUNCATED AT 250 WORDS)

Tentative analysis of the efficiency of fissure sealant in a public program in London.

A tentative analysis was made of the efficiency of allocating resources to fissure sealing, rather than to restorative care, in a public dental program. Data for the study were taken from a 2-year clinical trial in London. The analysis is necessarily tentative because the clinical trial employed the half-mouth design, which does not represent a true-life situation. Over the 2 years of the study, it was found that sealing the population of study teeth took from 24.9% to 33.8% more time than treating the lesions which developed in the control teeth would have. Reasons are given why this finding cannot be accepted as conclusive; rather, it is presented to raise questions and to stimulate additional studies into the efficiency of preventive programs. Guidelines for such studies, which should be conducted in different populations with varying caries prevalence, are suggested.

Diagnostic and preventive services in a national incremental dental plan for children.

A modelling exercise was carried out to examine the potential expenditure in a national incremental dental program for children aged six to 13. Using Relative Value Units (RVUs) as a proxy for dollars, the relative expenditures for care per child in fluoridated and fluoride-deficient areas were assessed. Dental treatment requirements were taken from existing data as far as possible. Arrangements for the delivery of care were based on existing pocicies of the American Dental Association, an services delivered were based on the recommendations of the American Academy of Pedodontics and the American Society of Dentistry for Children. Orthodontic care was limited to space maintainers and simple interceptive care. Children were assumed to receive initial care at age six, and annual maintenance care from ages seven to 13. The results showed that although restorative care would be 49.8 percent less expensive for children in fluoridated areas, total care would be only 11.9 percent less expensive. The major reason for this difference was the high proportion of annual maintenance-care costs that would be absorbed by diagnostic and preventive services using UCR fees. The necessity for much of this care is questioned under the conditions of this model, and some methods by which the dental profession might control the relatively high cost of diagnostic-preventive services are suggested.