The effect of xylitol chewing gums and candies on caries occurrence in children: a systematic review with special reference to caries level at study baseline

PURPOSE

A systematic review of published data was carried out to assess the caries-preventive effects of xylitol chewing gums and candies in children.

METHODS

Electronic and hand searches were performed to find clinical studies on the effects of xylitol chewing gums and candies on dental caries in children (≤ 18 years). Prospective randomised or controlled clinical trials published before 2023 were included in the review.

RESULTS

The initial search identified 365 titles to be evaluated. After applying inclusion and exclusion criteria, 15 articles with either fair or low quality were reviewed. Nine articles studied chewing gums, five candies, and one both of them. In the ten evaluated xylitol chewing gum studies xylitol consumption significantly reduced caries occurrence when compared with no treatment or a placebo polyol gum. The effect was clinically significant in studies with high or moderate caries level at study baseline. The results also suggested that the caries-reducing effect of xylitol gums may differ from sorbitol/polyol gums. In five of the six heterogenous xylitol candy studies, no caries-reducing effect was found independent of caries level. In addition to caries level, also the daily xylitol dose was a confounding factor.

CONCLUSION

The present findings suggest that the caries-reducing effect of adding xylitol chewing gum to the daily diet has been well demonstrated in children and adolescents with high or moderate caries level at study baseline. Xylitol gum use could benefit subjects with active incipient caries lesions on smooth tooth surfaces.

The effect of dietary intervention on paraffin-stimulated saliva and dental health of children participating in a randomized controlled trial

OBJECTIVES

The aim was to study the impact of dietary intervention on the properties of paraffin-stimulated saliva, and on dental caries.

STUDY DESIGN

At 7 months of age 1062 infants (540 intervention; 522 controls) started in the prospective, randomized Special Turku Intervention Project (STRIP) aimed at restricting the child's saturated fat and cholesterol intake to prevent atherosclerosis of adult age (www.clinicaltrials.gov NCT 00223600). At 3 years of age, every fifth child was invited to an oral sub-study, and 148 (78 boys) children attended. At 6, 9, 12 and 16 years of age 135, 127, 114 and 88 children were restudied, respectively. Dietary intakes of carbohydrates, protein, saturated fat, calcium, phosphate, and fibre were regularly recorded using 4-day food records. Height and weight were regularly monitored. Paraffin-stimulated saliva samples were collected at 6, 9, 12 and 16 years of age, and analyzed for flow rate, buffer capacity, calcium, phosphate and proteins. Dental health was recorded and expressed as d3mft/D3MFT, and as time of caries onset.

RESULTS

Dietary intakes of calcium, phosphate and fibre, and salivary flow rate increased with time in both groups (p<0.001, GLM for repeated measures). Fibre intake and salivary flow rate were higher in the intervention than in the control group (p=0.042 and p=0.0394, respectively, GLM for repeated measures). There were no correlations between dietary intakes and salivary concentrations of calcium or phosphate. Children who did not have caries experience (d3mft/D3MFT=0) during the entire follow-up had higher salivary calcium than those who had caries already at 3 years of age. The association between salivary calcium and caries onset was significant up to 12 years of age. Toothbrushing frequency was statistically significantly associated with caries-onset at ages 6 (gamma statistic 0.457, p=0.046) and 12 years (gamma statistic 0.473, p=0.019).

CONCLUSIONS

The current long-term dietary intervention increased children's paraffin-stimulated salivary flow rate. The concentration of salivary calcium was directly correlated to dental health. Higher salivary flow rate in the intervention group is believed to be due to higher fibre intake in the intervention group.

Administration of Bifidobacterium animalis subsp. lactis BB-12 in early childhood: a post-trial effect on caries occurrence at four years of age

Probiotic bifidobacteria are widely used in the prevention of childhood diseases. These bacteria are also associated with caries occurrence. The present secondary analysis in a low-caries population evaluated the effect of early administration of Bifidobacterium animalis subsp. lactis BB-12 (BB-12) on caries occurrence and identified markers of dental decay in early childhood. In the original randomized, double-blind, placebo-controlled study (NCT00638677, http://www.clinicaltrials.gov), infants (n = 106) received BB-12, xylitol or sorbitol tablets from the age of 1-2 months to 2 years with a slow-release pacifier or a spoon (daily dose of BB-12 10(10) colony-forming units, polyol 200-600 mg). The present data were collected using clinical examinations and questionnaires at the age of 4 years. The occurrence of dental caries was assessed using the International Caries Detection and Assessment System. Oral hygiene status and mutans streptococci (MS) levels were also determined. No differences were detected between the study groups in the occurrence of enamel caries (p = 0.268) or obvious dentinal caries (p = 0.201). The occurrence of caries was associated with daily consumption of sweet drinks (p = 0.028), visible plaque observed (p = 0.002) and MS detected in the dental plaque (p = 0.002). Administration of BB-12 in infancy does not seem to increase or decrease the occurrence of caries by 4 years of age in a low-caries population.

Bifidobacterium animalis subsp. lactis BB-12 administration in early childhood: a randomized clinical trial of effects on oral colonization by mutans streptococci and the probiotic

A randomized clinical trial studied the effects of early administration of Bifidobacterium animalis subsp. lactis BB-12 (BB-12) on oral colonization of (1) mutans streptococci (MS), and (2) BB-12. In this double-blind, placebo-controlled study, infants (n = 106) received probiotic bacteria (BB-12 group), xylitol (X group), or sorbitol (S group). Test tablets were administered twice a day (from the age of 1-2 months) with a novel slow-release pacifier or a spoon (daily dose of BB-12 10(10) CFU, polyol 200-600 mg). Samples were collected from mucosa/teeth at the age of 8 months and 2 years for BB- 12 determination (qPCR) and plate culturing of MS (MSB, TYCSB), lactobacilli (Rogosa) and yeasts (Sabouraud). The MS levels of the mothers were determined (Dentocult SM Strip Mutans). The baseline characteristics of the three groups were similar. Mean duration of tablet delivery was 14.9 ± 6.7 months. In all groups, >90% of the mothers showed high MS counts (log CFU ≥5). MS colonization percentages of the children at the age of 2 years were rather low (BB-12 group: 6%; X group: 31%; S group: 10%; p < 0.05). The levels of lactobacilli and yeasts did not differ between the groups. BB-12 cell counts barely exceeding the detection limit were found in three of the oral samples of the 8-month-old children; however, the 2-year samples did not contain BB-12. The early administration of BB-12 did not result in permanent oral colonization of this probiotic or significantly affect MS colonization in the children.

Dental fear: one single clinical question for measurement

A new dental fear measurement instrument, the Short Dental Fear Question (SDFQ), was developed and tested for clinical practice purposes. The correlations of the SDFQ with the Dental Anxiety Scale (DAS) and the Dental Fear Survey (DFS) were tested in 15-16-year-old adolescents. The Spearman correlations (rs) between the dental fear measurement instruments were: SDFQ – DFS: r_s = 0.79, n = 26; DFS – DAS: r_s = 0.72, n = 26; SDFQ– DAS: r_s = 0.69, n = 27. DAS and DFS mean scores were clearly higher in the SDFQ fear group than SDFQ in the relaxed group. The SDFQ is a short and compact instrument which might be convenient for the measurement of dental fear in clinical practice.

Sucrose intake since infancy and dental health in 10-year-old children

The dental health of children in western countries has improved without a concomitant decrease in the mean sucrose consumption. Our aim was to analyse the association of long-term sucrose consumption with dental health in children representing the highest (n = 33, 18 boys) and the lowest 5 percentiles (n = 33, 21 boys) of sucrose intake, in a study where food consumption was prospectively recorded from infancy to 10 years of age. The sum of decayed, missing and filled teeth in the primary (dmft) and permanent (DMFT) teeth was assessed. Children's sucrose intake in the high intake group was constantly higher than in their counterparts (p < 0.001), and already exceeded 10% of energy intake (E %) at 2 years of age. The mean +/- SD of the dmft + DMFT scores was higher in the high than in the low sucrose intake group (3.9 +/- 3.9 and 1.9 +/- 2.5, respectively; p = 0.032). We conclude that a persistently high sucrose intake increases the risk of dental caries in children.

Frequent exposure to invasive medical care in early childhood and operative dental treatment associated with dental apprehension of children at 9 years of age

AIM

This was to study prospectively a cohort of children as to whether behaviour at a 3-year examination, exposure to medical care and operative dental treatment are associated with each other, and with the level of dental apprehension at 9 years of age.

METHODS

Data were collected at three subsequent dental examinations of 126 children (67 boys, 59 girls). Cooperation, general health condition and operative dental treatment during the preceding 3 years were obtained at dental examinations with 3-year intervals, i.e. at 3, 6 and 9 years of age. Children's dental apprehension was assessed at the age of 9 years. The data were analysed using an ordinal logistic regression model.

RESULTS

Dental apprehension at 9 years of age was associated with frequent exposure to invasive medical care (p<0.001) and past experience of operative dental care (p<0.002), but not with cooperation at 3 years of age (p=0.124).

CONCLUSION

Frequent invasive medical care in early childhood and operative dental treatment, tooth extractions in particular, are associated with dental apprehension at 9 years of age.

Influence of maternal xylitol consumption on mother-child transmission of mutans streptococci: 6-year follow-up

Xylitol is effective as a noncariogenic or even cariostatic sugar substitute. Habitual xylitol consumption appears to select for mutans streptococci (MS) which shed easily into saliva from plaque. We have earlier shown that habitual xylitol consumption of mothers was associated with a statistically significant reduction in the probability of mother-child transmission of MS assessed at 2 years of age. The aim of the present study was to assess the children's MS counts 1 and 4 years after the maternal xylitol consumption had been discontinued. At baseline, during pregnancy, all mothers (n = 195) showed high salivary levels of MS. The mothers were randomly assigned to xylitol, fluoride (F) and chlorhexidine (CHX) groups. In the xylitol group, the mothers chewed xylitol-sweetened gum, for 21 months, starting 3 months after delivery. In the two control groups, the mothers received CHX or F varnish treatments at 6, 12 and 18 months after delivery. At the 2-year examination, 169 mother-child pairs participated. At the 3-year and 6-year examinations, there were 159 and 147 children in the study, respectively. For children's MS analyses, visible plaque was collected using toothpicks at the age of 3 and paraffin-stimulated saliva at the age of 6. The persons involved in the collection and analysis of the microbiological samples were blinded as to the study design and group. Both the plaque and salivary MS were cultured on Mitis salivarius agars containing bacitracin. In all groups, the colonization percentages increased during the follow-up. At the 3-year examination, the children's risk of having MS colonization was 2.3-fold in the F group (95% CI 1.3-4.2) compared to the xylitol group. This difference was statistically significant. Even at 6 years of age, the salivary MS levels were significantly lower in the xylitol group than in the other groups (ANOVA, p<0.001). In conclusion, the earlier demonstrated, xylitol-associated reduction in the probability of mother-child transmission of MS was still found in the children's MS counts at the age of 3 and 6 years.

Sealants and xylitol chewing gum are equal in caries prevention

Sealants and xylitol have been demonstrated to prevent dental decay, but their effect has never been compared in the same study. Regular use of xylitol chewing gum during 2 or 3 school years was compared with application of occlusal sealants in a randomized study. The reliability of the clinical observations was controlled by examining the presence of dental decay in the same teeth from bitewing radiographs in a blind study. After 5 years, no statistically significant differences between the sealant and xylitol groups were found. The results were in line with the results from separate studies with sealants or xylitol. There were no great differences between the costs of the measures. The selection between the compared preventive measures has to be made on the basis of practical aspects such as caries occurrence, availability of personnel and other resources, opportunity costs, cooperation with schools, and other local conditions.

Occurrence of dental decay in children after maternal consumption of xylitol chewing gum, a follow-up from 0 to 5 years of age

Studies have shown that prevention of mutans streptococci (MS) colonization in early childhood can lead to prevention of dental decay. In the microbiological part of the present study in Ylivieska, Finland, with 195 mothers with high salivary MS levels, regular maternal use of xylitol chewing gum resulted in a statistically significant reduction in MS colonization in their children's teeth at the age of 2 years compared with teeth in children whose mothers received fluoride or chlorhexidine varnish treatment. The children did not chew gum or receive varnish treatments. For the present study, the children were examined annually for caries occurrence by experienced clinicians who did not know whether the children were colonized with MS. Regardless of the maternal prevention group, the presence of MS colonization in children at the age of 2 years was significantly related to each child's age at the first caries attack in the primary dentition. In children at the age of 5 years, the dentinal caries (dmf) in the xylitol group was reduced by about 70% as compared with that in the fluoride or chlorhexidine group. We conclude that maternal use of xylitol chewing gum can prevent dental caries in their children by prohibiting the transmission of MS from mother to child.

Influence of maternal xylitol consumption on acquisition of mutans streptococci by infants

Xylitol is effective as a non-cariogenic sugar substitute. Habitual xylitol consumption appears to select for mutans streptococci (MS) with impaired adhesion properties, i.e., they shed easily to saliva from plaque. One hundred sixty-nine mother-child pairs participated in a two-year study exploring whether the mothers' xylitol consumption could be used to prevent mother-child transmission of mutans streptococci. All mothers showed high salivary levels of mutans streptococci during pregnancy. The mothers in the xylitol group (n = 106) were requested to chew xylitol-sweetened gum (65% w/w) at least 2 or 3 times a day, starting three months after delivery. In the two control groups, the mothers received either chlorhexidine (n = 30) or fluoride (n = 33) varnish treatments at 6, 12, and 18 months after delivery. The children did not chew gum or receive varnish treatments. MS were assessed from the mothers' saliva at half-year intervals and from the children's plaque at the one- and two-year examinations. The MS were cultured on Mitis salivarius agars containing bacitracin. The salivary MS levels of the mothers remained high and not significantly different among the three study groups throughout the study. At two years of age, 9.7% of the children in the xylitol, 28.6% in the chlorhexidine, and 48.5% in the fluoride varnish group showed a detectable level of MS. In conclusion, therefore, habitual xylitol consumption by mothers was associated with a statistically significant reduction of the probability of mother-child transmission of MS assessed at two years of age. The effect was superior to that obtained with either chlorhexidine or fluoride varnish treatments performed as single applications at six-month intervals.

Salivary buffer effect in relation to late pregnancy and postpartum

We studied the salivary pH, buffer effect (BE), and flow rates of unstimulated and paraffin-stimulated saliva of 8 women in their late pregnancy and postpartum. Salivary samples were collected about 1 month prior to and about 2 months after delivery. In non-pregnant control women, two paraffin-stimulated salivary samples were collected 1 month apart. The salivary BE increased significantly from late pregnancy to postpartum without exception. The increase was 2.04 +/- 1.17 pH units (P < 0.001) on average. The BE increased from 4.79 +/- 1.64 (final pH) to 6.82 +/- 1.01 (final pH). This change was not due to variation in salivary flow rates, since both unstimulated and paraffin-stimulated flow rates remained unchanged. In control women the difference between the 2 BE measurements was only 0.13 +/- 0.47 pH units on average. We concluded that women with high postpartum BE values may have moderate or even low BE values in late pregnancy. In control women, individual variation was found to be low in all variables studied.

The effect of repeated sampling on paraffin-stimulated salivary flow rates in menopausal women

Paraffin-stimulated whole-saliva samples of 12 post- and perimenopausal women were taken five times over a 7-week period. After 1 min of prestimulation, saliva was collected for 5 min under standardized conditions. Saliva was first collected on three consecutive days, and two additional samples were collected 6 and 7 weeks after the first. Salivary flow rates showed significant variation between samplings. The greatest difference appeared between the first and second collections. The increase in flow rates between these collections was significant (p = 0.003). The third successive collection also gave a significantly (p = 0.005) higher flow rate than the first. The 6-week and baseline samples were similar. The 7-week sample showed a significantly higher flow rate (p = 0.018) compared with the baseline value. These results stress the importance of standardization of sampling intervals when salivary flow rates are studied.

Multifactorial modeling for prediction of caries increment in adolescents

The purpose of the study was to develop a multifactorial model for the prediction of 11-month caries increment in adolescents. The mean age of the subjects (n = 181) at the base-line examination was 13 years and 3 months. The risk indicators consisted of past caries experience, white spot lesions, visible plaque, gingivitis, salivary secretion rate, buffer effect, sucrase, mutans streptococci, lactobacilli, and Candida. The multifactorial modeling included all the above risk indicators, age, and gender and resulted in different models in boys and girls, indicating the difficulty of caries prediction in adolescents. When boys and girls were combined, the final model included past caries experience, Candida, and salivary sucrase. Although the accuracy of the model was slightly below the 80% level recommended for screening purposes, the results provide clinically valuable information. The risk of caries increases with an increasing number of positive tests within the model.

Assessment of single risk indicators in relation to caries increment in adolescents

Base-line data on a series of risk indicators were related to 11-month caries increment in 181 subjects with a mean age of 13 years and 3 months. A caries increment equalling or exceeding one tooth surface was recorded in 21% of the subjects. The risk indicators consisted of past caries experience, white spot lesions, visible plaque and gingivitis, and six salivary tests: secretion rate, buffer effect, sucrase, mutans streptococci, lactobacilli, and Candida. Significant associations between caries increment and past caries experience (p = 0.002), white spot lesions (p = 0.01), lactobacilli (p = 0.02), Candida (p = 0.006), and sucrase (p = 0.02) were observed. The ensuing odds ratios were thus recorded: past caries experience, 3.6; white spot lesions, 2.9; salivary sucrase activity, 2.9; lactobacilli, 2.5; and Candida, 2.8.

Susceptibility of Streptococcus mutans and Streptococcus sobrinus to antimicrobial agents after short-term oral chlorhexidine treatments

Effects of three different types of short-term applications (1-3 times during 1 week) of chlorhexidine (1 or 40%) on the susceptibility of 863 clinical isolates of Streptococcus mutans and 53 isolates of Streptococcus sobrinus from 58 subjects were studied. Chlorhexidine-resistant isolates were not found either before or after the treatment. The minimum inhibitory concentrations (MICs) to chlorhexidine of all isolates of S. mutans were < or = 1 microgram/ml, and of S. sobrinus < or = 2 micrograms/ml. S. mutans and S. sobrinus were also susceptible to ampicillin, penicillin, cefuroxime, and tetracycline. In conclusion, different short-term chlorhexidine regimens do not induce resistance in S. mutans or S. sobrinus and, furthermore, these species have so far retained their susceptibility to common antibiotics.

A simple method for monitoring mutans streptococci in young children

The study assessed the practicability of the Dentocult-SM STRIP MUTANS test in children, using dental floss to transfer the dental plaque to the strip. The subjects were children of 2-3 yr (n = 365) and 5-6 yr (n = 398). The mutans streptococci count on the strip was found to be a good indicator of infection and was surprisingly accurate in the prediction of the 3-yr caries increment.

Comparison of the efficacy of 40% chlorhexidine varnish and 1% chlorhexidine-fluoride gel in decreasing the level of salivary mutans streptococci

The aim of the study was to compare the efficacy of a 40% chlorhexidine (CHX) varnish (EC40, Certichem, Nijmegen, The Netherlands) with a 1% CHX-0.2% NaF gel in decreasing the level of salivary mutans streptococci (MS). The subjects were screened for a high level of MS using a Dentocult-SM strip method (Orion Diagnostica, Finland). In varnish groups with fluoride (VCHXF, n = 20) and without fluoride (VCHX, n = 19), the CHX varnish was applied on dry teeth using an ampoule and an anesthetic syringe with blunt needle, and removed after 15 min. In group VCHXF an additional 2.26% fluoride varnish (Duraphat, Woelm Pharma GmbH, Eschwege, Germany) was applied. The CHX-NaF gel treatment included the application of the gel with rubber cups and dental tape for 5 min on three occasions during a week in group GCHXF (n = 21). The level of MS (MSB agar) was significantly lower after 4 weeks than at baseline in VCHX (p < 0.001) and VCHXF (p < 0.05), but not after 12 weeks. In GCHXF a significant decrease (p = 0.001) was observed after 4 weeks only with the strip method. In VCHX and VCHXF the strip values for MS were still reduced after 12 weeks. In VCHX and GCHXF a small, although statistically significant, increase was observed in the total number of microorganisms after 4 and 12 weeks. Opinions on taste sensations associated with the treatments were generally negative, but least negative in the VCHXF group; fewer side effects were also reported in the VCHXF group.(ABSTRACT TRUNCATED AT 250 WORDS)

Multifactorial modeling for root caries prediction: 3-year follow-up results

The study was part of a series aiming at the development of caries tests. The initial material (n = 104, age range 47-79 yr, mean 62 yr) was reduced to 96, who were observed for 3 yr. During the follow-up four subjects died, all due to myocardial infarction, and four refused to participate. Thorough oral examinations were conducted at the baseline, 1- and 3-yr registrations; coronal and root surface caries were registered separately according to WHO classification. The tests included salivary mutans streptococci, lactobacilli, candida/yeasts, secretion rate, buffer effect and sucrase activity, and quantitation of visible plaque. The association between prospective root caries increment and several tests was significant. Multifactorial modeling resulted in the combination of Past Root Caries Experience (OR 12.8), Lactobacilli (OR 8.6) and Candida (OR 2.8). At screening, the criterion "two or three positive tests" of these yielded acceptable accuracy (77.1) and a relative risk of 3.3.

Salivary flow rate, buffer effect, sodium, and amylase in adolescents: a longitudinal study

The study aimed to provide information on salivary secretion rate, buffer effect, sodium, total protein, and amylase in adolescence. Paraffin-wax-stimulated saliva was collected annually in 69 initially 10-yr-olds and in 98 initially 15-yr-olds. During the 5-yr follow-up, the rate of flow increased in both sexes in the younger age group. In the older age group there was only a slight increase in the flow within the 2-yr follow-up. In both age groups, girls tended to have lower secretion than boys. In cross-sectional analyses, the rate of flow correlated positively with buffer effect and sodium, and negatively with proteins. These findings are in line with earlier observations. However, with age, the buffer effect did not parallel the flow. At the base-line examination the buffer effect was lower in the 15-yr-old than in the younger age group. In line with that, a decrease was found at the final examination in the initially 10-yr-olds. This decrease was stronger in girls than in boys. The observed change in the buffer effect was not related to a parallel change in the flow rate or total protein and amylase content of saliva. In girls the change was, however, associated with a small, but statistically significant drop in the salivary sodium level. The variation in the buffer effect increased from the age of 12 to 15, especially in girls. This effect could not be demonstrated for the other flow-rate-associated variables used to monitor the functioning of the salivary glands.

Multifactorial modeling for root caries prediction

The study was part of a series of investigations aiming at the development of diagnostic caries tests for screening of risk subjects. The material consisted of 100 adult subjects (mean 62 yr, range 47-79 yr), 50 of these under chronic medication. The series of tests included two chairside registrations, i.e. incipient demineralization of exposed root surfaces without cavitation (RD 1) and quantitation of visible plaque (VPT%), three microbiological tests for mutans streptococci, lactobacilli, and candida/yeasts and three tests on stimulated saliva, i.e. secretion rate, buffering capacity and sucrase activity. A thorough clinical examination was conducted at the baseline and 1-yr registration phases, caries being registered at a tooth surface level according to WHO recommendations separately for coronal and root caries. Considerably more root caries than coronal caries developed during the observation period. For coronal caries increment, the predictive value of any of the tests was not significant. For root caries, however, the association between several tests and prospective caries increment was significant. Subsequent multifactorial modeling yielded the highest predictive value to the combination of Past Root Caries Experience (OR 25.0, Visible Plaque (OR 4.2), Candida (OR 8.0) and Lactobacilli (OR 5.8). A positive finding of Past Root Caries (RDFS) or the combination of the other three tests (Can, LB, VPT%) as criteria for selection in screening for root caries produced good accuracy (84.0) and a relative risk of 5.5.

Effects of low-dose oral contraceptives on female whole saliva

The composition and flow rate of paraffin-stimulated whole saliva were analysed in 22 women, of whom 11 used oral contraceptives and 11 did not. Ten men served as the controls. The salivary samples were collected during one month (oral contraceptive users and men), or during one menstrual cycle (non-users). The saliva analyses included flow rate, pH, buffer effect, sialic acid, thiocyanate, peroxidase, lysozyme, amylase, immunoglobulins A, G and M, total protein, mutans streptococci, lactobacilli, yeasts and total numbers of aerobic bacteria. The salivary buffer effect of oral contraceptive users was significantly (p less than 0.005) higher than that of non-users. All the other constituents showed intra- and interindividual variation in all groups, but with no apparent hormone-dependency.

Salivary lactobacilli and yeasts in relation to caries increment. Annually repeated measurements versus a single determination

The purpose was to compare annually repeated measurements with a single determination of salivary lactobacilli and yeasts in distinguishing subjects with high and low caries increments. The determinations were carried out using Dentocult and Oricult chair-side methods in connection with a 3-year oral health preventive program. The subjects were institutionalized Hungarian children (n = 257), ranging from six to eleven years of age. The data were analyzed by comparing the age-adjusted means of caries increment in subjects with positive and negative microbiological findings. In comparison with a single determination, two or three annual measurements of the tests proved to increase the ability to distinguish subjects with respect to the 3-year caries increment. The analysis of the repeated measurements providing longitudinal information of these microorganisms probably included the time factor required for development of caries.

Caries prediction through combined use of incipient caries lesions, salivary buffering capacity, lactobacilli and yeasts in Hungary [corrected]

The caries predictive value of incipient caries lesions (INC), salivary buffering capacity (DBPH), and salivary lactobacilli and yeasts (DCOC) was studied using logistic regression models. Additionally the effect of age was analysed. The subjects (n = 284) were from 7 to 12 yr of age (categorized less than or equal to 9 yr and greater than or equal to 10 yr). The measurements were carried out with Dentocult, Oricult and Dentobuff chair-side methods (Orion Diagnostica, Helsinki) in two groups of a field study. INC and DCOC contributed significantly to prediction in both groups. The estimated odds for being a caries active subject were about 20-fold in one group and 33.5-fold in greater than or equal to 10 yr in the other, when a child had positive values for INC and DCOC, in comparison with all negative values. Additionally DBPH had predictive value in both age categories in the latter group. Although the prediction was not perfect on an individual basis (correct in about 70% of subjects) the estimated odds-ratios clearly describe the differences in the susceptibility to caries. The results suggest that the present variables, especially in combination, have good ability to distinguish subjects in respect of high and low caries increment.

Screening of caries in children through salivary lactobacilli and yeasts

The caries predictive value of salivary counts of lactobacilli and yeasts was evaluated in 298 children (from 6 to 11 yr of age) concurrently to a 3-yr xylitol field study in Hungary. On a group level the salivary yeasts and the combined information of lactobacilli and yeasts predicted the 3-yr caries increment acceptably. On an individual basis salivary yeasts had more power than salivary lactobacilli. At best the sensitivity and specificity of yeasts were 74% and 75%, and the combined information of lactobacilli and yeasts, 69% and 83%, respectively. Although the results were not that good in all subgroups of the study, they indicate the value of salivary yeasts in caries prediction either as a sole test or together with salivary lactobacilli.

Collaborative WHO xylitol field studies in Hungary. VII. Two-year caries incidence in 976 institutionalized children

The aim was to assess caries increment as influenced by partial substitution of sucrose by xylitol (X group) over a 2-year period in comparison with systemic fluoride (F group) and restorative treatment only (C group). The study differed from the 3-year field study of the same series primarily in that existing base-line differences were eliminated because the protocol required that all the new subjects entering the institutions in the 1st year were to be included for a 2-year trial. During this period the number of dropouts was 243 (19.9% of all subjects), the final material consisting of 976 children (6-12 years old). The 2-year DMFS increment was 3.8 in the X group, 4.8 in the F group, and 6.0 in the C group. The corresponding ratio (RS) between caries incidence and the tooth surface population at risk was RSX, 4.5; RSF, 5.5; and RSC, 7.5. The xylitol regimen resulted in a lower increment of caries than measured in the F and C groups (p less than 0.001; convariance analysis, with base-line prevalence, number of permanent teeth, and visible plaque index as covariants.

Collaborative WHO xylitol field studies in Hungary. VI. Changes in the carbohydrate to protein ratio of dental plaque

The carbohydrate to protein ratio of dental plaque was analyzed in a field study assessing the effect of partial substitution of dietary sucrose by xylitol (X group) in comparison with systemic fluoride (F group) and restorative treatment solely (C group). The biochemical analysis was supplemented by quantitative assessment of plaque through the visible plaque index (VPI). The present substudy was carried out cross-sectionally and longitudinally (n = 83) in initially 6- to 11-year-old children. Missing base-line values for the carbohydrate to protein ratio were partly compensated for through reexamination of the carbohydrate to protein ratio 15 months after termination of the trial. The latter series served as reference to indicate the base-line situation. A lower carbohydrate to protein ratio was measured in the X and F groups than in the C group. Improvement of the VPI values was obtained only in the X group. Our results suggest the potential value of parallel quantitative and qualitative assessment of plaque.

Collaborative WHO xylitol field studies in Hungary. V. Three-year development of oral hygiene

The oral hygiene conditions were evaluated within a 3-year field study aimed at assessing the cariostatic value of partial substitution of sucrose by xylitol (X group) in comparison with systemic fluoride (F group) and restorative treatment only (C group). Parallel to caries and further associated studies the visible plaque index, based on the total number of permanent and deciduous teeth, was determined longitudinally at annual examinations in 688 institutionalized children, initially 6 to 11 years old. The observations were analyzed with regard to sex, age, experimental grouping, and total development. The oral hygiene conditions were generally poor. At the base-line examination only 26% of the children had acceptable oral hygiene; at the end this level was reached by 42%. A definite improvement was measured only in the X group, in which the final values differed significantly (p less than 0.001) from the base-line values and also from the end situation in the F and C groups. It is concluded that the development was influenced by several factors, such as different snacking habits and access to sweets, the study per se, and xylitol-induced effects.

Collaborative WHO xylitol field studies in Hungary. II. General background and control of the dietary regimen

The consumption of sucrose and xylitol and the exposure to fluoride (F) were analyzed in a field study aimed at assessing the value of peroral xylitol as a caries-preventive measure. The coverage of the general background referred to the conditions of 689 institutionalized children observed for a 3-year-period. The material in the dietary substudy consisted of 286 subjects aged 8-13 years. The intake and excretion of F was monitored at all institutions in a total of 380 children. The frequency of the consumption of sucrose was high, its intake increasing over the weekend in comparison with weekdays. The consumption of the xylitol-containing products did not reduce the frequency of sucrose intake. Varying and fluctuating levels of exposure to systemic F was registered, as also reflected in the urinary F/creatinine quotient.

Collaborative WHO xylitol field studies in Hungary. III. Longitudinal counts of lactobacilli and yeasts in saliva

The levels of salivary lactobacilli and yeasts were determined annually in half of the subjects of the xylitol (X) and fluoride (F) groups of a 3-year caries study. These measurements were carried out with Dentocult (DC) and Oricult (OC) dip-slide methods. A high level of lactobacilli prevailed throughout the study in these subjects. Significant changes were registered in some subgroups--that is, improvement in one of the X institutions and worsening in one of the F and one of the X institutions. At base line the counts of OC were worse in the X than in the F group. In the total material some improvement occurred during the course of the study, mainly in the X group. The changes associated with the preventive program should also be considered as related to the improvement in oral hygiene, restorative treatment, and the mere study effect.

Collaborative WHO xylitol field studies in Hungary. IV. Saliva levels of Streptococcus mutans

Salivary Streptococcus mutans was quantified to detect possible age-, sex-, and group-dependent differences at the end of a 3-year field study assessing the value of partial substitution of sucrose with xylitol (X group) in comparison with systemic administration of fluoride (F group) and restorative treatment solely (C group). The material of this substudy consisted of 390 institutionalized children aged 9-14 years. S. mutans was determined through the spatula technique and grouped into categories 0, less than 10(5), 10(5)-10(6), and and greater than 10(6) CFU/ml saliva. Zero to less than 10(5) values included more than 80% of the subjects of the X group. The cross-sectional comparison between groups showed lower S. mutans values in the X group than in the F and C groups. These differences between groups were highly significant. S. mutans was not dependent on age or sex.

Collaborative WHO xylitol field studies in Hungary. I. Three-year caries activity in institutionalized children

The aim of this 3-year field study was to assess the value of partial substitution of sucrose with peroral xylitol (14-20 g/day) as a caries-preventive measure (X group) in comparison with systemic administration of fluoride (F group) and restorative treatment procedures solely (C group). An F dentifrice was used unsupervised in the X and F groups, the former containing 10% xylitol. The C group used customary, predominantly F-free dentifrices distributed by the local health authorities. The final material consisted of 689 institutionalized children (6-11 years). Caries was scored yearly in duplicate by two continuously calibrated teams. At base line the X group had a significantly higher caries prevalence than the F and C groups. The 3-year DMFS increment was 4.2 in the X group, 6.5 in the F group, and 7.7 in the C group. The corresponding ratio (RS) between caries incidence and the tooth surface population at risk was RSx, 4.9; RSF, 6.6; and RSC, 8.6. It is concluded that dietary xylitol in solid sweets resulted in a lower increment of caries than obtained in the F and C groups (p less than 0.001, covariance analysis, with base-line prevalence, number of permanent teeth, and visible plaque index as covariants).