Newer Approaches to Preventing Dental Caries in Children

Although the incidence of dental caries has shown a general decline during the past few decades, it still remains a significant health problem in children. The role of mutans streptococci in the caries process is discussed, including its transmission from mother to child during a discrete "window of infectivity." Anticipatory guidance -- an approach used to better intercept the caries process to prevent it from progressing -- is discussed. This program is introduced during infancy and is adapted to the child's particular needs as he or she matures. Anticipatory guidance allows for the implementation of some newer preventive strategies. Following the determination of mutans streptococci levels in at-risk infants and their mothers, a prevention program can be provided to both. Through proper education, various forms of topical fluoride supplementation, and antimicrobial therapy, it is hoped that newer preventive strategies can more effectively reduce the threat of caries at a much younger age than previously possible.

Despite progress made during the past 20 to 30 years, dental caries remains a significant health problem affecting infants and children. It accounts for significant discomfort, lost time from school, and visits to the emergency room. In assessing the current methods for preventing and treating dental caries in children, one may wonder whether dentists truly utilize a preventive model; or if, perhaps, they should approach the problem differently. This paper is an attempt to present some of the newer philosophies regarding the process of dental caries in children and provide a glimpse of where dentistry may be headed with prevention strategies.

Recent epidemiologic studies have demonstrated that the caries rate has shown an overall decline during the past two to three decades. Data from previously published studies was summarized in a 1996 paper by Brown, Kaste, and Selwitz.¹ From 1971 to 1974, 26 percent of children from 5 to 17 years old were found to have caries-free permanent teeth, with a mean DMFS of 7.1 surfaces in children having cavities. From 1988 to 1991, the percentage of children with caries-free permanent teeth increased to 54.7 percent, with a corresponding decrease in the mean DMFS to 2.5 surfaces in children with cavities.

In a similar study conducted by the National Institute of Dental Research in 1986-1987, 49.9 percent of the children examined had no decay found in their permanent teeth.² Caution needs to be exercised in interpreting the above data, and a different picture emerges when the numbers are further analyzed. An excellent discussion related to interpreting this data can be found in a paper by Edelstein and Douglass.³ The 50 percent figure reported represents an average of children who had a caries-free permanent dentition from the ages of 5 to 17 years. In actuality, 97.3 percent of 5-year-olds and 15.6 percent of 17-year-olds were caries-free. It should not be surprising that less than 3 percent of 5-year-olds display decay in newly erupted permanent molars. Turning the 15.6 percent value around, 84.4 percent of 17-year-olds were found to have dental caries, affecting, on the average, eight or more tooth surfaces.³ This is a significant number.

An interesting finding was that caries activity in children is unequally distributed, with approximately 25 percent of children and adolescents from age 5 to 17 having 80 percent of the caries found in permanent teeth.⁴ Vargas, Crall, and Schneider⁵ found that African-American and Mexican-American children had approximately twice the incidence of caries and higher levels of untreated carious lesions than Caucasian children. In addition, lower-income children were found to have a higher caries rate and more unmet dental treatment needs than higher income populations. In fact, according to population projections, these segments of the population are expected to increase during the next six decades.⁶ California is expected to have an increase of 3.2 million children and will have the largest Caucasian, Asian-American, and Hispanic populations by the year 2020.⁷

These data have addressed dental caries involving the permanent dentition. Is dentistry doing any better in preventing disease when dentists direct their energies to treating children in the primary and early mixed dentition stages of development? As reported by Edelstein and Douglass,³ the 1986-1987 NIDR findings regarding dental caries in primary teeth were that mean dfs was found to be 3.4 at age 5, increasing to 3.9 by age 9. If the average 3-year-old has three carious primary tooth surfaces and the average 9-year-old has four carious primary tooth surfaces, it is obvious that preventive efforts need to be directed toward children at a much younger age.

When examining the epidemiology of dental caries affecting primary teeth, the reader must again be cognizant of the uneven distribution noted above. Many of the studies involving preschool children come from examining Head Start program populations, which are made up of lower-income children, age 3 to 5. In summarizing the data, Edelstein and Douglass reported that from 16 percent to 65 percent of the preschool children enrolled in Head Start programs require dental treatment.³ According to Vargas, Crall, and Schneider,⁵ in 2- to 5-year-old children at or below 100 percent of the federal poverty line, almost 80 percent of decayed primary teeth have not been restored. So not only is there significant caries in this population, but there is also an issue of access to dental care.

A significant number of preschool children are already found to have dental caries by the age of 2 to 5. A reasonable question to ask at this time is: How early might caries activity develop in children? This becomes an important question for prevention.

For the answer to this question, one needs to revisit a pattern of dental caries affecting infants and toddlers that has previously been called either baby bottle tooth decay or nursing decay. At a 1994 workshop sponsored by the Centers for Disease Control and Prevention, the term early childhood caries was introduced to describe dental caries that begin on the primary incisors prior to age 36 months.⁸ The problem affects infants and preschoolers who were exposed to improper feeding practices involving baby bottles or breast-feeding. Two excellent reviews by Ripa ⁹ and Milnes¹⁰ summarize previous epidemiologic studies regarding the incidence of early childhood caries. In the United States, the prevalence of early childhood caries ranged from 1 percent in a population of Los Angeles children to 72 percent of Navajo and 55 percent of Cherokee children examined in Head Start centers. The great variability in these findings can be attributed to different criteria used for diagnosis, the conditions under which the examinations were completed, and differences in the populations examined.

Treatment of early childhood caries can be expensive, often requiring extensive restorative treatment and extraction of teeth at a very early age. The cost of the restorative treatment was found to range from $170 to $2,212 by Ramos-Gomez and colleagues.¹¹ In addition to these costs, general anesthesia may add another $1,000 to $6,000 if the child needs to be hospitalized.¹²

Mutans Streptocci

It has been known for some time that early childhood caries is an infectious and transmissible disease primarily related to the presence of cariogenic bacteria known as mutans streptococci (MS).¹³ Mutans streptococci are only present in the mouth of infants following the eruption of teeth or when there is a nonshedding surface in the mouth, such as an acrylic obturator.¹⁴ MS cannot colonize within the mouth without hard surfaces. The infant acquires MS from his or her mother through frequent and intimate contact. Interestingly, Li and Caufield ¹⁵ found that the genotypes of the MS identified in the infants studied were identical to those found in their mothers an average of 71 percent of the time. In female infants, this specificity increased to 88 percent as opposed to 53 percent found between male infants and their mothers. In no instance was there a match between the infant's strains and their fathers’, nor between the fathers’ and their spouses’. According to Slavkin,¹⁶ one reason for this similarity between the MS found in mothers and their infants might relate to the transfer of maternal immunoglobulins via the placenta and breast milk and corresponding transmission of the mother’s immune specificity. The "exogenous" bacteria of the father would thus be excluded from colonizing the infant’s mouth, while selecting for the mother’s "indigenous" organisms.

Maternal levels of MS relate to the ability to transmit the organism to the infant. Children whose mothers had low concentrations of salivary MS rarely harbored these microorganisms. Conversely, children whose mothers exhibited high salivary levels tended to have significant infection, according to Berkowitz.¹⁴ MS usually constitutes less than 1 percent of the plaque flora in children with negligible caries activity but exceeds 50 percent of the total cultivable plaque flora in children with nursing caries. The frequency of infant infection was found to be approximately nine times greater when maternal salivary levels of MS exceeded 10⁵ colony forming units (CFU) per ml as compared to maternal salivary MS levels of 10³ CFU per ml.¹⁴

This explains where the infant acquires MS. A more interesting story is when the bacteria are transmitted to the infant. The initial colonization of MS occurs during a discrete period of time, or "window of infectivity," occurring between 19 and 31 months, with a median age of 26 months.¹⁷ This timing corresponds with the eruption of the first and second primary molars, which provide a large surface area as well as grooved and fissured surfaces for colonization.¹⁸ Other studies, however, point to an earlier window for MS colonization, occurring before 12 months of age, coinciding with eruption of the incisors.¹⁹ After the window closes at 31 to 33 months, there essentially are no new tooth surfaces to become colonized in the mouth, so MS would have trouble becoming established. There is speculation that a second window occurs at the time of eruption of the first permanent molars and incisors at age six, but this has yet to be determined.¹⁸

Mutans streptococci is only one group of many organisms found in the mouth. More than 400 species can be found in adults, each in its own niche.¹⁶ There is an ecological succession of organisms that begins shortly after birth and continues into adulthood. For example, S. sanguis colonizes the mouth of infants from approximately 9 to 12 months of age. It competes with and influences the later colonization of MS during its window of infectivity. Dasanayake and colleagues²⁰ hypothesized that by giving the younger child antibiotics, the environment becomes more favorable for MS colonization due to its affect on S. Sanguis.

Dental caries is considered a multifactoral process, involving other variables in addition to pathogenic microorganisms. One such piece of the puzzle is the "substrate" to which the child is exposed. Oral bacteria thrive in an environment rich in carbohydrates. Whether the infant goes to bed with a bottle of formula or juice or frequently snacks on cariogenic foods, the frequent and prolonged consumption of foods known to lower plaque pH is very important. Such a diet can greatly facilitate an increase in the population of MS, which can lead to a high risk for rampant decay.¹³

What parents place in the infant’s bottle does have some significance in determining the cariogenic potential of the solution. Sheikh and Erikson²¹ studied eight different infant formulas and found that they all were capable of significantly reducing plaque pH. The cariogenic potential of bovine milk has recently come under question. A review by Seow¹³ indicated that bovine milk, by itself, may not be cariogenic. In a recent study by Erickson and Mazhari,²² human breast milk, although it supported bacterial growth and was not a good buffer, also did not appear to be cariogenic. More studies are necessary to definitively establish the cariogenicity of these fluids.

Parents also place other liquids in baby bottles. Siener and colleagues²³ interviewed women in three California counties regarding feeding practices of their infants. Fifty-three percent owned baby bottles having popular soft drink, juice, or Kool-Aid logos. Thirty-one percent of the children were actually given Kool-Aid or soda to drink from these bottles. The parents most likely to establish this practice were younger, poorly educated individuals from lower socioeconomic groups.

There is another variable in the equation -- the susceptible host. How can dentists make the dentition of the host or young child less susceptible to attack? In trying to prevent the process of early childhood caries from occurring in the infant, it would appear that there are two avenues that can be taken. The first intervention would be to work toward preventing damage caused by bacteria from occurring to the child’s healthy mouth by controlling the substrate and providing aggressive oral hygiene measures (primary prevention). The second intervention would be to educate and treat the mother to attempt to prevent or minimize the spread of infection to her infant (primary-primary prevention).²⁴ These goals are not mutually exclusive and form the basis of some newer approaches to prevention that are dependent on early identification and intervention prior to the birth of the child or while the child is young enough so that disease can truly be prevented.

Prevention

The current practice of physicians providing intraoral prevention and care as a part of routine well-baby visits and deferring the child’s first visit to the dentist until age 3 to 4 is not optimally effective in preventing dental caries. Many physicians are not adequately prepared to deal with issues related to oral health. In a study by Sanchez and colleagues,²⁵ pediatricians and family physicians practicing in Alabama were surveyed and were generally found to understand the importance of oral health. However, most physicians received two hours or less of education in preventive dentistry during their medical and/or specialty training and indicated on the survey the need to increase their knowledge in this area.

With the initial dental visit being so late, the child in many cases is seen by the dentist after the caries process has begun. This approach is based on the traditional view that caries are inevitable. The responsibility of the dentist was to repair the damage caused by the disease and then institute prevention.²⁶ This approach is not truly preventive and does not catch the process at an early enough time to be effective. Since the process of early childhood caries begins much earlier than 3 to 4 years of age, to more optimally prevent the disease, a strategy that includes earlier intervention must be initiated.

That is the rationale of the American Academy of Pediatric Dentistry in recommending that infants receive their initial professional evaluation by a dentist by approximately 12 months of age or shortly after the primary teeth begin to erupt.²⁷ It is hoped that by scheduling the initial appointment at an early age and providing counseling and intervention to parents, early childhood caries and other potential problems can be anticipated and prevented. In fact, the phrase, "anticipatory guidance" was borrowed from pediatricians, who have adopted this concept as part of well-child care visits. According to Nowak and Casamassimo,²⁸ anticipatory guidance is the "process of providing practical, developmentally appropriate health information about children to their parents in anticipation of significant physical, emotional, and psychological milestones. This information guides parents by alerting them to impending changes, teaching them their role in maximizing their children’s developmental potential and identifying their children’s special needs." It is a proactive counseling process in which parents are questioned about their child’s level of dental development ("dental developmental milestones"), and risk assessment is used to identify areas in which education or intervention are needed.

Preventive measures for the child would change as the child gets older and his or her needs change. For example, oral hygiene for the infant must be carried out by the parents while the 10-year-old should be able to take responsibility for his or her own care. Fluoride requirements would change with age and circumstance. Sealants would be discussed at the time that susceptible molars erupt. Use of a mouthguard would be encouraged when the child participates in contact sports. The process of anticipatory guidance would begin with the earliest visit to the dentist and would continue as the child matures, changing in anticipation of each child’s needs at each point in time.

For the purpose of discussion, a child’s developmental age range can be divided into different stages and particular developmental milestones can be associated with each period. The first period would be from 6 to 12 months of age. This corresponds to the eruption of the first teeth into the oral cavity. The second period would be from 12 to 24 months, during which the primary dentition is completed. The third period would be from 2 to 6 years. During this period, the child would experience the loss of the first primary teeth and the eruption of the permanent molars and/or incisors. From 6 to 12 years, the child would be in the mixed dentition stage of development. He or she would experience losing the remaining primary molars and canines with the eruption of the corresponding succedaneous canines and premolars. The anticipatory guidance process can extend into the adolescent period, from 12 to 18 years of age and beyond, into adulthood (Table 1). During every period of development, there are issues that need to be addressed. The dental professional is in an ideal position to anticipate the potential problems that may occur during each developmental period and provide the patient or his or her parents with the information necessary to prevent or mitigate any potential problems. Each time the infant or young child is examined by the dentist, the anticipatory guidance process may be utilized to address any risk factors related to the following components: the child’s health history, diet and nutrition status, fluoride adequacy, oral habits, injury prevention, oral development, and oral hygiene (Table 2).

At the initial examination of a 6- to 12-month-old having discoloration of the erupting primary teeth, questions related to the health history might be relevant for problems occurring during pregnancy that could affect the development of the primary teeth. Diet and nutrition questions would determine whether the baby uses a bottle at bedtime or engages in on-demand breast-feeding. Does the child drink from a cup? A discussion of injury prevention would include a discussion of using car seats and making the home child-proof for the toddler. A discussion of oral development would prepare the parent for the pattern and timing of tooth eruption and problems related to teething. A discussion of oral hygiene would be important at this time to educate the parent in brushing the teeth as soon as they erupt and to use a smear or pea-sized amount of fluoridated toothpaste (with the ADA Seal of Acceptance).

For the 12- to 24-month-old, the process of anticipatory guidance might focus in the area of diet and nutrition. The child should be weaned from the bottle or breast, and the parent should be aware of the role of carbohydrates in the caries process. Fluoride adequacy should be established to ensure maximum protection. Oral hygiene would be critical at this point, considering the role of MS in the caries process and the window of infectivity during which it colonizes the child’s mouth. Making sure that the child and his or her mother both attain optimal levels of oral hygiene is important during this critical time. Determining the MS levels in both the mother and child would be of great benefit in assessing the risk of developing early childhood caries. When dentists begin to adopt these strategies, they are adopting a more microbiologic approach to dental caries. When they can begin to anticipate that this period is critical to the early colonization of MS and the risk of developing early childhood caries, they may be able to prevent the process from occurring. By treating the child at this early age, the dentist has begun the process of prevention two to three years earlier than it is traditionally done.

For the 2- to 6-year-old, discussion of oral habits might be relevant. A child that sucks on a finger when he or she is in the mixed dentition stage requires a different intervention than a toddler with the same habit. Oral development can be revisited at this time to explain the pattern and timing of eruption of the permanent teeth to the parent. Oral hygiene is again discussed as the child should take greater responsibility in his or her home care, and flossing should be instituted as the interproximal contacts close.

For the 6- to 12-year-old child, injury prevention is an important area to discuss. At this age, many children are active in organized sports, and some sports-related injuries can be prevented through the use of a mouthguard. Oral development would be important to discuss during this period. Permanent molars are erupting, and the benefits of pit and fissure sealants should be presented. Also, issues related to early tooth loss, space maintenance, and treatment of problems in occlusal development should be discussed.

The process of anticipatory guidance continues throughout the different age ranges and stages of development and can be extended into adulthood. The adult patient may be counseled regarding anticipated problems that may develop affecting the dentition and periodontium related to advancing age.

As has been discussed, through anticipatory guidance, potential problems may be anticipated and parents and patients educated. The next step in crafting an optimal prevention program is to identify appropriate interventions that can be utilized in addressing these potential problems.

Fluoride

An obvious place to start a preventive program would be with fluoride. Water fluoridation continues to be a very effective, cost-efficient, and safe public health method for preventing dental caries in children.²⁹ In the 1986-87 NIDR study previously discussed, Waldman noted that children raised in communities having optimal water fluoridation were found to have DMFS scores approximately 18 percent below those of children without water fluoridation. This protection was noted to be most effective on smooth tooth surfaces.³⁰ Many communities in California have not had the benefits of fluoridated water, although recent legislation could change this situation. In October 1995, the Statewide Fluoridation Bill (AB733) was signed into law. The bill allows for the fluoridation of water systems in California with 10,000 or more service connections (serving approximately 25,000 or more residents). Funding comes from government grants, foundations, and other sources.³¹ It is now believed that a low-dose, high-frequency topical application of fluoride is the main mechanism for preventing caries, whether it is provided through water fluoridation, fluoride rinses, chewable tablets, or dissolvable lozenges. Water fluoridation provides a topical benefit to the teeth several times a day, whenever water, or foods or juices prepared with fluoridated water, come in contact with the teeth.^29,32 According to Featherstone,³³ the level of fluoride provided from drinking water serves to inhibit demineralization and enhance remineralization of teeth.

Since, for the present, many communities in California do not have water fluoridation available, other methods of delivering fluoride topically to the teeth need to be considered.

Toothpaste containing fluoride, when used consistently, is an effective method for reducing the incidence of caries.³⁴ Most toothpastes available in the United States contain from 1,000 to 1,100 ppm of fluoride. After a person brushes and rinses, fluoride levels in their saliva rapidly decline. However, some fluoride "deposits" form on the soft tissues and provide additional fluoride as they gradually deplete.²⁹ By the time they reach 18 to 24 months of age, most children have their teeth brushed with a fluoride-containing dentifrice.³⁵ In light of the "window of infectivity" related to the colonization of the mouth by MS, to be effective, toothbrushing must be instituted at a much earlier age. How well parents are doing in brushing their infants’ teeth comes from a study by Levy and colleagues³⁶ in which the authors found that approximately 12.9 percent of 6-month-olds, 36.7 percent of 9-month-olds and 64.5 percent of 12-month-olds had their teeth brushed, primarily by the mother. Among parents who used dentifrice, 94 to 97 percent used fluoridated dentifrice, with approximately 0.25 g of toothpaste or less (0.25 mg of fluoride) placed on the brush. The amount of toothpaste needed to form 0.25 g would be considered to be pea-sized, which is the amount currently recommended by the American Dental Association and the American Academy of Pediatric Dentistry.³⁷

Children younger than 6 swallow a large percentage of the toothpaste placed on the toothbrush, causing much of the toothpaste to be absorbed in the gastrointestinal tract.³⁸ The significance of swallowing toothpaste is important for the child who already is exposed to additional sources of fluoride in the diet and/or via supplements. The Fluoride Supplement Schedule, which was modified by the American Dental Association in 1995, serves as a guide to the amount of supplemental fluoride that a child should receive, related to age and amount of fluoride in the water system (Table 3).³⁹ If a 12-month-old child is having his or her teeth brushed twice daily, resides in a community with optimal fluoride in the water and is receiving additional supplementation, the child could be receiving well more than the recommended 0.25mg/day fluoride. Pendrys³⁸ studied the causes of fluorosis in a sample of teenagers from an optimally fluoridated community. The author found that 71 percent of the fluorosis cases were related to a history of exceeding the recommendation for the amount of toothpaste placed on the toothbrush. Inappropriate fluoride supplementation accounted for 25 percent of the cases of fluorosis.

Although providing adequate amounts of fluoride is an important preventive measure, there is a danger in overprescribing fluoride supplements. Another source of fluoride for infants comes from commercially available infants foods and dry cereals. Heilman and colleagues⁴⁰ found that fluoride concentrations ranged from 0.01 to 8.38 micrograms of fluoride per gram. Dry infant cereals reconstituted with fluoridated water and infant foods containing chicken both could provide significant amounts of fluoride to the infant.

Fluoride varnish has been used in Europe with generally favorable results and has recently been introduced into the United States as Duraflor, a 5 percent neutral sodium fluoride varnish. In a review of previous studies, DeBruyn and Arends⁴¹ cited a caries reduction rate in the permanent dentition of from 18 to 56 percent. Effectiveness in the primary dentition, however, has been inconclusive. Studies are being conducted in the United States that will provide more information on whether this technique should be routinely incorporated into an early preventive program.

Although fluoride is able to significantly reduce decay involving smooth tooth surfaces, it is least effective in preventing occlusal surface decay. In fact, 84 percent of caries in 5- to 17-year-olds involves the occlusal pits and fissures.³ Dental sealants are a very effective technique for preventing pit and fissure decay, with five-year retention rates of from 67 to 87 percent.⁴² There is evidence that placement of the sealant is itself responsible for causing a reduction in MS levels on the treated occlusal surfaces.⁴³ Despite its effectiveness, only about 19 percent of children age 5 to 17 had sealants placed on permanent teeth, with only 1.4 percent of children from 2 to 11 having any sealants placed on primary teeth.¹

One area showing promise comes from incorporating a fluoride-release mechanism into pit and fissure sealants. Not only would the occlusal surfaces of permanent and primary molars benefit from sealing of the pits and fissures, but fluoride has also been shown to reduce enamel demineralization on areas adjacent to the sealant.^44-46 The addition of fluoride does not seem to decrease the retentiveness of the sealant; however, much of the fluoride release may be of only short duration.⁴⁷ There is evidence that when fluoride-depleted restorations are subjected to a four-minute topical acidulated phosphate fluoride treatment, as is routinely done on a semiannual basis in most dental offices, the restorations again release significant amounts of fluoride, after being "recharged."^48,49

As was previously discussed, the traditional methods currently in use have not been very effective in preventing early childhood caries in very young children. Delivering preventive services to the children with the highest risk for developing dental caries is often difficult. For children from lower socioeconomic environments, a more community-based or school-based model may be appropriate for delivery of early preventive and interceptive services. Anticipatory guidance programs, parent education, brushing or rinsing programs with fluoride supplements, and/or application of fluoride varnish are some of the services that could be provided from a public health perspective.⁵⁰ Educational programs that have been directed toward pregnant women or new parents have been found to be somewhat effective.¹² Ripa ⁹ reviewed some of these programs and recommended that they be made an essential part of preventive programs targeting high-risk groups.

By considering early childhood caries to be an infectious disease, additional preventive strategies become available. This will most likely become a more significant factor in future prevention strategies. Dentists now have the ability to determine the intraoral MS levels in children and their mothers. This, in turn, allows the provision of various microbiologically based interventions for the at-risk child and his or her mother, thus influencing the level and timing of MS colonization. In a recent study by Lopez and colleagues,⁵¹ infants at high risk for developing early childhood caries (12 to 19 months of age) had either 10 percent povidone iodine or placebo applied to their teeth every two months during an average of about seven months. The authors found that placement of the antimicrobial solution over the teeth significantly reduced the incidence of early childhood caries. In a study of older children, age 8 to 10 years, either a chlorhexidine varnish or gel was applied to the teeth or patients brushed daily with chlorhexidine toothpaste. All regimens were capable of reducing salivary MS levels; however, the authors noted that the interdental MS colonization was relatively unaffected by the intervention.⁵²

Luoma and colleagues⁵³ studied the effects of daily rinsing with a solution of chlorhexidine and sodium fluoride in 11- to 15-year-old schoolchildren. After two years, both the caries rate and level of gingivitis were reduced compared with the other groups studied. In another use of chlorhexidine, 4- to 12-year-olds using a nightly chlorhexidine varnish-filled mouthguard for one week were reported to have significantly reduced MS levels over a three-month period.⁵⁴ There is a need for more clinical study of povidone iodine, chlorhexidine, and other antimicrobial agents before antimicrobial treatment can be routinely prescribed for children, especially infants and preschoolers. It is uncertain whether chlorhexidine represents a viable antimicrobial to use in children to prophylactically limit the MS population. It appears, however, that short-term chlorhexidine regimens do not select for resistant MS species.⁵⁵

According to Gunay and colleagues,²⁴ the prevention of dental decay in the healthy mouth of a young child is termed "primary prevention." To take prevention of early childhood caries a step further, "primary-primary prevention" begins even earlier and targets pregnant women. Mothers-to-be were taught how to care for their own mouths and provided with dietary counseling, professional prophylaxis, necessary restorative treatment, topical fluoride varnish application, and chlorhexidine mouthrinsing. They were also taught how to provide oral hygiene care for their baby, given instruction in proper infant dietary habits, and the abovementioned preventive services were phased in as the baby matured.²⁴ After following the babies for up to four years, the authors found statistically significant differences from a control group of children.

Targeting pregnant mothers in an effort to prevent early childhood caries in their children appears to be a promising strategy. Brambilla and colleagues⁵⁶ provided pregnant women with daily chlorhexidine rinses during the last six months of their pregnancy and every six months for the next two years. This intervention significantly reduced salivary MS levels in the mothers and delayed colonization of MS in their children. Similar findings were noted by Tenovuo and colleagues⁵⁷ and by Kohler and colleagues⁵⁸ when prevention programs targeted mothers of infants, prior to colonization of MS in the child.

Conclusion

There is a new paradigm for looking at the caries process in children. Caries is a transmissible process from the mother to the infant, and MS colonizes the mouth of the infant during a discrete "window of infectivity." This information provides dentists with the basis for designing a prevention program that approaches the caries process at an earlier age and in a more microbiologic manner. By incorporating the procedures of anticipatory guidance into their armamentarium, dentists can identify infants at high risk for developing early childhood caries. Through preventive techniques aimed at the mother-infant pair, the caries process can truly be prevented. Some of the modalities to prevent the process are currently available. More study is needed prior to recommending the routine use of antimicrobials in children at this time, although these techniques will likely prove to be effective when the proper agents are selected.

Author/

Richard D. Udin, DDS, is the chairman of the Department of Pediatric Dentistry at the University of Southern California School of Dentistry.

References/

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To request a printed copy of this article, please contact/Richard D. Udin, DDS, Department of Pediatric Dentistry, USC School of Dentistry, 925 W. 34th St., Room 4308, Los Angeles, CA 90089.