Dental Health: The Facts
Introduction
The major source of knowledge concerning the prevalence of dental health problems comes from periodic national surveys. In 1971-1974, the National Center for Health Statistics conducted the National Health and Nutrition Examination Survey (NHANES I) on a representative sample of the U.S. population. The survey included information concerning prevalence of caries, periodontal disease, edentulousness, and other dental health problems among children and adults. A 1979-1980 National Caries Prevalence (NCP) survey conducted by the National Institute of Dental Research (NIDR) assessed the dental health of U.S. school children aged 5-17. In 1983-1984, the Indian Health Service conducted a cross-sectional study of clinical patients to assess the dental health among American Indian and Alaskan natives. The dental health data that follows comes largely from those national surveys. Fluoridation data is collected and reported by the Centers for Disease Control. In late 1986, the National Institute of Dental Research will complete an Adult Oral Health Survey, which will provide updated Information about progress made in improving dental health among adults.
The prospects of prevention in dental health are encouraging. The use of fluoride at optimal levels before and after eruption of permanent teeth reduces the amount of caries an average of 50%-60%. Newly developed and under-utilized dental sealants can result in a 90% reduction in caries in treated teeth after one year, and a 55% reduction after six years. Lack of public and professional acceptance is a major factor limiting the effectiveness of these currently available prevention strategies.
Prevalence
Caries—Children
The 1979-1980 National Caries Prevalence (NCP) survey of U.S. school children aged 5-17 revealed that, on average, a school child had at least 1 caries lesion in permanent teeth by age 8,4 caries by age 12 and 11 by age 17.
The NCP survey estimated the caries prevalence in the permanent dentition for U.S. school children age 5-17 to be 4.77 decayed, missing or filled tooth surfaces (DMFS) per child and 2.91 decayed, missing or filled teeth (DMFT) per child.
A 1971-1974 National Center for Health Statistics (NCHS) Health and Nutrition Examination Survey (NHANES I) reported that children 1-5 years old averaged 1 primary tooth that was either decayed, nonfunctional-carious or filled.
School children aged 5 years in the 1979-1980 NCP survey averaged over 4 decayed or filled surfaces. Children 5-9 years old averaged 5.3 decayed or filled surfaces and 2.6 decayed or filled teeth per child in their primary dentition.
In the 1979-1980 NCP survey, 36.6% of U.S. school children aged 5-17 had no decayed, missing or filled teeth (DMFT), 39.8% had 1-4 DMFT, 15.9% had 5-8 (DMFT); and 7.7% had 9 or more (DMFT).
White children had more caries (4.89 DMFS per child) than children of other races (4.15 DMFS per child), according to the 1979-80 NIDR survey.
A 1983-1984 study of American Indian and Alaskan Native (AI/AN) children indicated that AI/AN children aged 5-19 years had an average of 6.8 DWI, compared to an average of 4.8 DMFT among 5-17 year olds in the general U.S. population reported by the NCP survey.
Between 1971 and 1974, children 6-11 years old who ate 20% of their total calories as between-meal sweets had 20% more decayed, missing and filled teeth than those children who did not have between-meal sweets.
Among school children in the 1979-1980 survey, 16.8% of the DMF surfaces were classified as decayed and unfilled, while 76.1% had been filled or restored by dental treatment, thereby indicating a relatively high level of restorative dental care among U.S. school children.
Marked regional variation in caries prevalence among U.S. school children exists. Children from the Northeast have been reported to have the highest mean number of decayed, missing and filled surfaces (DMFS) at 6.1 compared to children from the Southwest with 3.4 DMFS.
In the Southwest, 45% of the children are caries-free, compared to 30% of the children in the Northeast.
Caries—Adults
The 1971-1974 National Health and Nutrition Evaluation Survey (NHANES I) revealed that adults aged 18-74 years with at least one natural tooth averaged 16.9 decayed, missing or filled permanent teeth per person, including 1.4 untreated decayed permanent teeth.
Blacks aged 18-74 years averaged 4.7 fewer DMFT than whites in NHANES I. Women of all races averaged 1.2 more DMFT than men, while black women averaged 2.9 more DMFT than black men.
The 1982 National Health Interview Survey reported 11.4 million days of restricted activity, 4.16 million days of bed disability, 2.01 million days of work loss and 1.37 million days of school loss as a result of 3.21 million dental conditions.
Periodontal Disease
The 1979-1980 National Caries Prevalence Survey (NCP) of U.S. school children reported that 92% of the children had moderate gingival treatment needs, 3% had severe needs and 5% had no gingival treatment needs.
NHANES I showed that 31% of U.S. adults 18-79 years old had destructive periodontal disease and 25% had gingivitis.
The prevalence and severity of periodontal disease increases with age and is more common among males than females.
Periodontal index (PI) is a composite index used in oral epidemiological surveys to indicate the presence and severity of disease in the supporting tissues of the teeth. The PI ranges from 0 (indicating no inflammation) to 8 (indicating advanced destruction). The 1971-74 NHANES I survey showed that persons not brushing their teeth daily had a mean periodontal index of 3.54, whereas persons brushing once daily had a mean PI of 1.40, and persons brushing twice daily had a mean PI of 1.05.
The same survey revealed that nonsmokers had a mean PI of 1.01 compared to current smokers whose mean PI was 1.55.
Edentulous Persons
14.7% of the U.S. population aged 18-74 years were missing all of their teeth, according to NHANES I data.
Dental Treatment Needs
A 1975-1976 study showed that more than 9.5 million persons received medical care each year for craniofacial injuries.
Oral Cancer
In 1981, 27,000 new cases of oral cancer were diagnosed, and 9,000 cancer deaths were attributed to oral cancers.
Fluoride
The natural fluoride concentration in domestic water in the U.S. supplies ranges from 0.1 to 10 mg/L. Sea water contains fluoride at 1.0 to 1.5 mg/L.
Fluoride ingested at optimal levels before eruption of permanent molars reduces caries an average of 50%-60%. Reduction of caries continues at 50%-60% only if fluoride in water at 1 mg/L washes over teeth for the lifetime of the teeth.
The use of fluoride at optimal concentrations results in a 75% decrease in premature extraction of teeth among children.
Persons with the highest concentration of fluoride in the enamel of their teeth had more than 50% fewer decayed, missing and filled teeth than persons with the lowest fluoride concentration in a 1971-1974 national survey.
Public and Professional Awareness
When asked about factors important to preventing tooth decay in a 1985 National Health Interview Survey (NHIS), 95% of those surveyed said seeing a dentist regularly, 78% said drinking water with fluoride from childhood, and 96% said regular brushing and flossing teeth.
When asked about the main cause of tooth loss in children in the above survey, 58% said tooth decay; 30% said injury to the teeth; 8% said gum disease; and 4% did not know.
When asked about the main cause of tooth loss in adults during the same survey, 55% listed gum disease; 40% tooth decay; 2% injury to teeth; and 3% did not know.
In a survey for the American Dental Association (ADA), 94% of respondents said they brush their teeth. Of those respondents that brush, 64% do so at least once a day, and an additional 23% brush after each meal.
In the ADA survey, 38% of persons responding floss their teeth. Of the respondents aged 30-40, 47% stated that they flossed their teeth.
In the ADA survey, almost one third of respondents reported visiting a dentist within 6 months of the interview, 23% had visited a dentist between 6 months to 1 year, and 22% had not visited a dentist for 3 years or longer.
Preliminary analyses of the 1983 National Health Interview Survey indicate that 94% of people using a dentifrice use a brand containing fluoride.
Service Delivery
In 1983, there was an average 1.8 dental visits per person in the U.S. 51.8% of Americans in 1983 had visited a dentist in less than one year, 23.7% had not visited a dentist in two or more years and 10.8% had never visited a dentist.
According to the Health Care Financing Administration, $25.2 billion was spent on dentist services in 1984. This represents 6.5% of the total national health expenditures for that year.
In a 1978 survey for the American Dental Association, 26% of respondents had some form of dental insurance. Of those with dental insurance, 79% received it as a job-related benefit.
Mandatory football and ice hockey mouthguard rules exist through the National High School Federation, National Collegiate Athletic Association and the Amateur Hockey Association of the United States.
Fluoridation
The Centers for Disease Control estimates that as of December 1985, 130 million Americans (or 54.8% of the U.S. population) were served by fluoridated water. This figure includes 10.7 million persons who received water with natural fluoridation and 119.3 million who received water adjusted to achieve optimal fluoridation.
In December of 1985, 87.2% of the 236.2 million persons in the U.S. received public water supplies and 62.8% of those on public water supplies were served by fluoridation.
As of December 1985, 41 of the 50 largest U.S. cities had fluoridated water supplies.
28 states, Puerto Rico, and Washington, D.C. provide fluoridated water to over half their populations.
The World Health Organization has estimated an average savings of $40 in costs of dental care per $1 of expense for community foundation worldwide. In the U.S., the benefit-cost ratio for fluoridation of water supplies has been estimated at $50: $1.
Significant Trends
Caries—Children
Surveys of school children revealed a one third reduction in caries prevalence from 1971-1973 to 1979-1980.
Periodontal Illness
National surveys of periodontal disease in adults 18-79 years of age reveal that nearly twice as many people in 1971-1974 were without periodontal disease as in 1960-1962. In 1971-1974, 45.3% of males and 57.1% of females 18-79 years old were without periodontal disease, compared to 20.9% and 31.0% (respectively) in 1960-1962.
Edentulous Persons
Young adults aged 18-24 years had, on the average, 2.3 fewer missing teeth in 1971-1974 than in 1960-1962.
Fluoridation
Since the introduction of the practice of adjusting fluoride levels in community water systems in 1945, the number of people with access to water with optimal levels of fluoride for caries reduction (0.7 parts per million or higher) has increased steadily to an estimated 130.8 million in 1985, approximately 54.8% of the total U.S. population.
Special Issues
Fluoridation Growth Slow
In 1975, 60% of the population on community water systems received fluoridated water. By December 1984, the proportion of those served by community water systems who were receiving fluoridation rose to 62.8%.
Dental Sealants
55% of caries in children 5-17 years old develops in the pits and grooves of the chewing surfaces of teeth where the benefits of fluoride are least effective. Dental sealants are plastic resins which are applied to these occlusal surfaces to prevent caries formation.
A review of studies of a popular dental sealant showed 89%-96% retention of the sealant after 1 year and 58%-68% retention after 6 years. The sealants effectiveness at preventing caries when compared to untreated teeth was 89%-91% at 1 year and 55-56% at 6 years.
A national survey revealed that in 1982, 42% of dentists in private practice were not using dental sealants.
Nursing-Bottle Tooth Decay
The practice of leaving babies with bottles containing sugared liquids results in widespread caries referred to as nursing-bottle tooth decay. A 1983-1984 Indian Health Service (IHS) study showed that up to 50% of American Indian/Alaskan Native (Al/AN) preschool-aged children who seek dental services suffer from nursing-bottle tooth decay. Over 40% of AI/AN children under age 5 years had 7 more decayed and/or filled primary teeth in the IHS study. Children with nursing-bottle caries had almost 4 times the amount of tooth decay as those children without nursing-bottle caries.
A study of children ages 3-5 in Head Start programs in Ohio revealed that 14%-15% of children in urban fluoridated areas and 18% of children in urban nonfluoridated areas had nursing-bottle tooth decay.
Smokeless Tobacco
National data suggest that 12 million people used some form of smokeless tobacco in 1985. It is estimated that 16% of 12-17 year-old males used smokeless tobacco in 1985.
A North Carolina study of women who use smokeless tobacco revealed a 4.2% increase in the relative risk of oral cancer among snuff users.
Steven Parker
