Lead exposure and periodontitis in US adults.

BACKGROUND AND OBJECTIVE: Lead is known to have significant effects on bone metabolism and the immune system. This study tested the hypothesis that lead exposure affects periodontitis in adults. MATERIAL AND METHODS: This study used the data from the Third National Health and Nutrition Examination Survey (NHANES III, 1988-94). It analyzed data from 2500 men and 2399 women, 20-56 yr old, who received complete periodontal examination. Periodontitis was defined as the presence of > 20% of mesial sites with >or= 4 mm of attachment loss. Lead exposure was grouped into three categories: < 3; 3-7; and > 7 microg/dL. Covariates were cotinine levels, poverty ratio, race/ethnicity, education, bone mineral density, diabetes, calcium intake, dental visit, and menopause (for women). All analyses were performed separately for men and women and considering the effect design. Univariate, bivariate, and stratified analysis was followed by multivariable analysis by estimating prevalence ratios through poisson regression. RESULTS: After adjustment for confounders, the prevalence ratios, comparing those with a lead blood level of > 7 microg/dL to those with a lead blood level of < 3 microg/dL was 1.70 (95% confidence interval (CI): 1.02, 2.85) for men and 3.80 (95% CI: 1.66, 8.73) for women. CONCLUSION: The lead blood level was positively and statistically associated with periodontitis for both men and women. Considering the public health importance of periodontitis and lead exposure, further studies are necessary to confirm this association.

Carbonated soft drinks and dental caries in the primary dentition.

We analyzed fluid intake data among children aged 2-10 years from a 24-hour dietary recall interview in the NHANES III (1988-94) to investigate the effect of high consumption of carbonated soft drinks on caries in the primary dentition. We used cluster analysis to determine fluid consumption patterns. Four distinct fluid consumption patterns were identified: high carbonated soft drinks, high juice, high milk, and high water. About 13% of children had a high carbonated soft drink consumption pattern; they also had a significantly higher dental caries experience in the primary dentition than did children with other fluid consumption patterns. A fluid intake pattern comprised mainly of milk, water, or juice was less likely to be associated with dental caries. Findings of this study suggest that high consumption of carbonated soft drinks by young children is a risk indicator for dental caries in the primary dentition and should be discouraged.

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.

Fluorosis development in seven age cohorts after an 11-month break in water fluoridation.

This study used an 11-month break in water fluoridation to identify the time when developing incisors are most sensitive to fluorosis development. The study was based in Durham, NC, where an interruption to water fluoridation occurred between September, 1990, and August, 1991. A total of 1896 children was dentally examined. Fluorosis was measured by the TF index, and parents or guardians completed a questionnaire on demographics and fluoride history. Age cohorts ranged from those born 5 years before the break, to those born 1 year after the resumption of fluoridation. Fluorosis prevalence for seven age cohorts whose birth years ranged from 1985-86 to 1991-92 was 57.1, 62.3, 33.0, 32.3, 39.8, 30.2, and 36.8%, respectively. Children aged from birth to 3 years at the break, and those born 1 year after it, had less fluorosis than those aged 4-5 years at the break.

Sugared soda consumption and dental caries in the United States.

Because of the complexity of the caries process, the potential cariogenicity of specific food items is difficult to assess. The purpose of this study was to investigate the associations between sugared soda consumption and caries. Dietary and dental examination data from the 1988-94 Third National Health and Nutrition Examination Survey (NHANES III) were used. From the food frequency questionnaire and 24-hour recall data, significant associations between DMFS and soda consumption were generally seen in persons over age 25. No differences in DMFS, relative to soda consumption, were seen in persons under age 25, or in analyses of dfs for children under age 12. The observed associations could be due to the cumulative effects of the long-term consumption of sugared soda. The absence of apparent effects of sugared soda consumption in younger people may also be related to the increased use of fluorides since the 1960s.

Definitions of risk.

Risk-related terms such as risk factor, modifiable risk factor, demographic risk factor, risk indicator, determinant, and risk marker are often not well defined in the literature. This short report supports the use of a 1996 definition of risk factor, as probably the most commonly used term related to risk, for the Consensus Development Conference on Diagnosis and Management of Dental Caries Throughout Life, March 26-28, 2001.

Sugar consumption and caries risk: a systematic review.

This systematic review addresses the question: In the modern age of extensive fluoride exposure, do individuals with a high level of sugar intake experience greater caries severity relative to those with a lower level of intake? The MEDLINE and EMBASE databases were searched for English-language papers published between 1980 and 2000 using a search expression developed in conjunction with an experienced librarian. There were 809 papers located in the initial search. A review of titles and abstracts to identify clearly irrelevant papers reduced this number to 134. Two readers each read one half of these papers, and application of predetermined inclusion/exclusion criteria reduced this number of papers to sixty-nine. Criteria were established for scoring the quality of each of these papers on evidence tables. The maximum score for each paper was 100; the sixty-nine papers rated scored between 12 and 79. Final judgment of results was limited to those thirty-six papers that scored 55 or higher on the evidence tables and that reported studies carried out in countries where there is moderate-to-extensive fluoride exposure. Results showed that only two papers found a strong relationship between sugar consumption and caries development, sixteen found a moderate relationship, and eighteen found weak-to-no relationship. It was concluded that the relationship between sugar consumption and caries is much weaker in the modern age of fluoride exposure than it used to be. Controlling the consumption of sugar remains a justifiable part of caries prevention, however, if not always the most important aspect.

Does low birthweight increase the risk of caries? A systematic review.

Low birthweight is a major public health and social problem in the United States. While a long list of mortality and morbidity conditions have been associated with low birthweight, dental conditions have not received much attention. This systematic review addresses this question: Do low-birthweight children (birthweight <2500 grams) subsequently develop more caries than do children with normal-to-high birthweight? The MEDLINE and EMBASE databases were searched for English-language papers published between January 1966 and July 2000 using a search expression developed in conjunction with an experienced librarian. There were 198 papers located in the initial search; a title and abstract review to identify clearly irrelevant papers reduced this number to 37. Two readers each read these papers, and application of predetermined inclusion/exclusion criteria reduced this number to only four papers. Quality criteria were established for scoring each of these papers on evidence tables. The maximum score for each paper was 100; the four papers rated scored between 31 and 61. Results showed that no relationship between low birthweight and subsequent development of caries was reported in any of the four papers. However, conclusions must be cautious because of the scarcity of studies on the subject and the limited scope of the four papers judged. The relationship of low birthweight to subsequent development of caries, especially in the permanent dentition, needs further exploration.

Fluid consumption related to climate among children in the United States.

OBJECTIVE: Recommended fluoride concentrations in US public water systems are between 0.7-1.2 ppm, depending on the mean daily maximum temperature. This range assumes that water intake is higher in warmer than in cooler climates, based on research from the 1950s. The aim of this analysis is to relate fluid consumption among American children aged 1-10 years to the local climate under modern conditions. METHODS: The quantities of daily total fluid intake per body weight (ml/kg) and plain water intake per body weight (ml/kg) of children were calculated from the 24-hour recall diet survey in the third National Health and Nutrition Examination Survey (NHANES III, 1988-94). The mean daily maximum temperature from 1961 to 1990, averaged for the month during which the NHANES III exam was conducted, was obtained for each survey location from the US Local Climate Historical Database. Multiple regression analysis was conducted using SAS and SUDAAN. RESULTS: Fluid intake was significantly associated with age, sex, socioeconomic status (SES), and race and ethnicity. No significant association could be found between the amount of either total fluid or plain water intake and mean daily maximum temperature, either before and after controlling for sex, age, SES, and race or ethnicity. CONCLUSIONS: Results indicate that there is no evidence that fluid consumption among children is significantly related to mean temperature in modern conditions. This suggests that the national temperature-related guidelines for fluoride concentration in drinking water may be due for reevaluation.

Water consumption and nursing characteristics of infants by race and ethnicity.

OBJECTIVES: The purpose of this project was to determine racial/ethnic differences in water consumption levels and nursing habits of children younger than 2 years old. METHODS: Data from the 1994-96 Continuing Survey of Food intakes by individuals (CSFII) were used for these analyses. Water consumption and breast-feeding data on 946 children younger than 2 years old were used. RESULTS: For black non-Hispanic children younger than 2 years old (n = 121), 5.3 percent of the children were currently being breast fed. This percentage was less than that seen in other racial/ethnic groups. For white non-Hispanic children (n = 620), this percentage was 10.8 percent; for Hispanic children (n = 146), 12.2 percent; for "other" children, 18.5 percent (n = 59). Black non-Hispanic children had the highest total water consumption (128.6 ml/kg/day) among all groups, white non-Hispanic had the lowest (113.2 ml/kg/day). These differences were not statistically significant in multivariate regression modeling. Black non-Hispanic children also drank more tap water (21.3 ml/kg/day) than white non-Hispanic children (12.7 ml/kg/day) and Hispanic children (14.9 ml/kg/day). The difference was statistically significant in multivariate regression modeling. CONCLUSIONS: The differences in breast feeding and water consumption observed among black children younger than 2 years of age could be a factor in the observed higher levels of fluorosis in black children compared to other children.

The effects of a break in water fluoridation on the development of dental caries and fluorosis.

Durham, NC, fluoridated since 1962, had an 11-month cessation of fluoridation between September, 1990, and August, 1991. The purpose of this study was to assess the effects of this break on the development of caries and fluorosis in children. Study participants were continuously-resident children in Kindergarten through Grade 5 in Durham's elementary schools. There were 1696 children, 81.4% of those eligible, for whom a questionnaire was completed and clinical data recorded. Age cohorts were defined by a child's age at the time that fluoridation ceased. Caries was recorded in children in the Birth Cohort through Cohort 3, and fluorosis for children in Cohorts 1 through 5. Caries was assessed in the primary first and second molars according to the decayed-filled index; fluorosis on the labial surfaces of the upper permanent central and lateral incisors was assessed by the Thylstrup-Fejerskov (TF) index. Mother's education was associated with caries; higher education of the mother had an odds ratio of 0.53 (95% CI 0.40, 0.76) for caries in the child. No cohort effects could be discerned for caries. Overall prevalence of fluorosis was 44%. Prevalence in Cohorts 1, 2, 3, 4, and 5 was 39.8%, 32.3%, 33.0%, 62.3%, and 57.1%, respectively. These cohort differences remained statistically significant in regression analysis. It was concluded that while the break had little effect on caries, dental fluorosis is sensitive to even small changes in fluoride exposure from drinking water, and this sensitivity is greater at 1 to 3 years of age than at 4 or 5 years.

Oral Chlamydia trachomatis in patients with established periodontitis.

Periodontitis is considered a consequence of a pathogenic microbial infection at the periodontal site and host susceptibility factors. Periodontal research supports the association of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, and Bacteroides forsythus, and periodontitis; however, causality has not been demonstrated. In pursuit of the etiology of periodontitis, we hypothesized that the intracellular bacteria Chlamydia trachomatis may play a role. As a first step, a cross-sectional study of dental school clinic patients with established periodontitis were assessed for the presence of C. trachomatis in the oral cavity, and in particular from the lining epithelium of periodontal sites. C. trachomatis was detected using a direct fluorescent monoclonal antibody (DFA) in oral specimens from 7% (6/87) of the patients. Four patients tested positive in specimens from the lining epithelium of diseased periodontal sites, one patient tested positive in healthy periodontal sites, and one patient tested positive in the general mucosal specimen. In conclusion, this study provides preliminary evidence of C. trachomatis in the periodontal sites. Planned studies include the use of a more precise periodontal epithelial cell collection device, the newer nucleic acid amplification techniques to detect C. trachomatis, and additional populations to determine the association of C. trachomatis and periodontitis.

Water consumption in the United States in 1994-96 and implications for water fluoridation policy.

OBJECTIVES: The purpose of this project was to describe current water consumption patterns and to compare them to findings from earlier studies. Current water consumption data also were used to reevaluate the association between water consumption and climate. These findings are of importance in estimating fluoride intake from fluoridated water. METHODS: Findings from the 1994-96 Continuing Survey of Food Intakes by Individuals (CSFII) were compared to those from two earlier dietary studies, the 1977-78 Nationwide Food Consumption Survey (NFCS) and the pioneering research of Galagan and colleagues in the 1950s. Food consumption data were analyzed for 14,619 persons with food and beverage intake data for two 24-hour periods in the CSFII. RESULTS: Increased consumption of infant formulas and decreased consumption of tap water and cow's milk were seen in the CSFII for infants compared to the NFCS. Older children and adults showed increased consumption of carbonated beverages and juices. While Galagan and colleagues found about a 60 percent increase in water consumption between the coldest (55 degrees F) and warmest (85 degrees F) conditions, only a 20 percent difference was seen between the winter and summer months in certain regions in the CSFII. CONCLUSIONS: No obvious strong or consistent association between water intake and month or season was apparent in these recent data. These findings are preliminary, and suggest that water fluoridation policy requires further research regarding water consumption and climate.

The case for eliminating the use of dietary fluoride supplements for young children.

Fluoride supplements have been used for years to prevent dental caries; nevertheless, there are three reasons why their use is inappropriate today among infants and young children in the United States. Evidence for the efficacy of fluoride supplements when used from birth or soon after is weak, supplements are a risk factor for dental fluorosis, and fluoride has little preeruptive effect in caries prevention. While there are many reports on the caries-preventive efficacy of supplements, few meet standards for acceptability as clinical trials, and those that do have tested chewable tablets or lozenges under supervision in school-aged children. North American children today are exposed to fluoride from many sources--drinking water, toothpaste, gels, rinses, and in processed foods and beverages. The additional cariostatic benefits that accrue from using supplements are marginal at best, while there is strong risk of fluorosis when young children use supplements. Available evidence suggests that the public is more aware of the milder forms of fluorosis than was previously thought; thus, it is prudent for caries-preventive policies to aim to maximizing caries reductions while minimizing the risk of fluorosis. It is therefore concluded that the risks of using supplements in infants and young children outweigh the benefits. Because alternative forms of fluoride for high-risk individuals exist, fluoride supplements should no longer be used for young children in North America.

Evidence-based dentistry. It's development and use in clinical practice.

Science and technology are developing so rapidly that dental practitioners have to constantly assess whether the materials and procedures they are using in their practices still represent the best treatment for their patients. But busy practitioners have little time to research these questions on their own, and their attempts to do so are frequently handicapped by the lack of in-depth training in the skills required to distinguish good science from poor science. The emergence of evidence-based dentistry, a process for ensuring that the treatment we provide our patients is justified by the best available scientific evidence, holds promise for making this problem more manageable.

Fluorosis risk from early exposure to fluoride toothpaste.

UNLABELLED: Swallowed fluoride toothpaste in the early years of life has been postulated to be a risk factor for fluorosis, but the epidemiological evidence is weakened by the fact that most of the relevant studies were done in developed countries where an individual is exposed to multiple sources of fluoride. OBJECTIVES: To quantify the risk of fluorosis from fluoride toothpaste in a population whose only potential source of fluoride was fluoride toothpaste. METHODS: Case-control analyses were conducted to test the hypothesis that fluoride toothpaste use before the age of 6 years increased an individual's risk of fluorosis. Data came from a cross-sectional clinical dental examination of schoolchildren and a self-administered questionnaire to their parents. The study was conducted in Goa, India. The study group consisted of 1189 seventh grade children with a mean age of 12.2 years. RESULTS: The prevalence of fluorosis was 12.9% using the TF index. Results of the crude, stratified, and logistic regression analyses showed that use of fluoride toothpaste before the age of 6 years was a risk indicator for fluorosis (OR 1.83, 95% CI 1.05-3.15). Among children with fluorosis, beginning brushing before the age of 2 years increased the severity of fluorosis significantly (P<0.001). Other factors associated with the use of fluoride toothpaste, such as eating or swallowing fluoride toothpaste and higher frequency of use, did not show a statistically significant increased risk for prevalence or severity of fluorosis. CONCLUSIONS: Fluoride toothpaste use before the age of 6 years is a risk indicator for fluorosis in this study population.

Glycemic control and alveolar bone loss progression in type 2 diabetes.

This study tested the hypothesis that the risk for alveolar bone loss is greater, and bone loss progression more severe, for subjects with poorly controlled (PC) type 2 diabetes mellitus (type 2 DM) compared to those without type 2 DM or with better controlled (BC) type 2 DM. The PC group had glycosylated hemoglobin (HbA1) > or = 9%; the BC group had HbA1 < 9%. Data from the longitudinal study of the oral health of residents of the Gila River Indian Community were analyzed. Of the 359 subjects, aged 15 to 57 with less than 25% radiographic bone loss at baseline, 338 did not have type 2 DM, 14 were BC, and 7 were PC. Panoramic radiographs were used to assess interproximal bone level. Bone scores (scale 0-4) corresponding to bone loss of 0%, 1% to 24%, 25% to 49%, 50% to 74%, or > or = 75% were used to identify the worst bone score (WBS) in the dentition. Change in worst bone score at follow-up, the outcome, was specified on a 4-category ordinal scale as no change, or a 1-, 2-, 3-, or 4-category increase over baseline WBS (WBS1). Poorly controlled diabetes, age, calculus, time to follow-up examination, and WBS1 were statistically significant explanatory variables in ordinal logistic regression models. Poorly controlled type 2 DM was positively associated with greater risk for a change in bone score (compared to subjects without type 2 DM) when the covariates were included in the model. The cumulative odds ratio (COR) at each threshold of the ordered response was 11.4 (95% CI = 2.5, 53.3). When contrasted with subjects with BC type 2 DM, the COR for those in the PC group was 5.3 (95% CI = 0.8, 53.3). The COR for subjects with BC type 2 DM was 2.2 (95% CI = 0.7, 6.5), when contrasted to those without type 2 DM. These results suggest that poorer glycemic control leads to both an increased risk for alveolar bone loss and more severe progression over those without type 2 DM, and that there may be a gradient, with the risk for bone loss progression for those with better controlled type 2 DM intermediate to the other 2 groups.

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.

Non-insulin dependent diabetes mellitus and alveolar bone loss progression over 2 years.

This study tested the hypothesis that persons with non-insulin dependent diabetes mellitus (NIDDM) have greater risk of more severe alveolar bone loss progression over a 2-year period than those without NIDDM. Data from the longitudinal study of the oral health of residents of the Gila River Indian Community were analyzed for 362 subjects, aged 15 to 57, 338 of whom had less than 25% radiographic bone loss at baseline, and who did not develop NIDDM nor lose any teeth during the 2-year study period. The other 24 subjects had NIDDM at baseline, but met the other selection criteria. Bone scores (scale 0-4) from panoramic radiographs corresponded to bone loss of 0%, 1%-24%, 25%-49%, 50%-74%, or 75% and greater. Change in bone score category was computed as the change in worst bone score (WBS) reading after 2 years. Age, calculus, NIDDM status, time to follow-up examination, and baseline WBS were explanatory variables in regression models for ordinal categorical response variables. NIDDM was positively associated with the probability of a change in bone score when the covariates were controlled. The cumulative odds ratio for NIDDM at each threshold of the ordered response was 4.23 (95% C.I. = 1.80, 9.92). In addition to being associated with the incidence of alveolar bone loss (as demonstrated in previous studies), these results suggest an NIDDM-associated increased rate of alveolar bone loss progression.

Dental caries and dental fluorosis at varying water fluoride concentrations.

OBJECTIVES: The purpose of this study was to investigate the relationships between caries experience and dental fluorosis at different fluoride concentrations in drinking water. The impact of other fluoride products also was assessed. METHODS: This study used data from the 1986-87 National Survey of US School-children. Fluoride levels of school water were used as an indicator of the children's water fluoride exposure. The use of fluoride drops, tablets, professional fluoride treatments, and school fluoride rinses were ascertained from caregiver questionnaires. Only children with a single continuous residence (n = 18,755) were included in this analysis. RESULTS: The sharpest declines in dfs and DMFS were associated with increases in water fluoride levels between 0 and 0.7 ppm F, with little additional decline between 0.7 and 1.2 ppm F. Fluorosis prevalence was 13.5 percent, 21.7 percent, 29.9 percent, and 41.4 percent for children who consumed < 0.3, 0.3 to < 0.7, 0.7 to 1.2, and > 1.2 ppm F water. In addition to fluoridated water, the use of fluoride supplements was associated with both lower caries and increased fluorosis. CONCLUSIONS: A suitable trade-off between caries and fluorosis appears to occur around 0.7 ppm F. Data from this study suggest that a reconsideration of the policies concerning the most appropriate concentrations for water fluoridation might be appropriate for the United States.