Effect of long-term consumption of milk supplemented with probiotic lactobacilli and fluoride on dental caries and general health in preschool children: a cluster-randomized study

The aim of this study was to evaluate the effect of milk supplemented with probiotic bacteria and fluoride on caries development and general health in preschool children. Children 1-5 years of age (n = 248) attending 14 day care centres with 27 units in northern Sweden entered the study. The centres were randomly assigned to two parallel groups: children in the intervention group were served 150 ml milk supplemented with Lactobacillus rhamnosus LB21 (10(7) CFU/ml) and 2.5 mg fluoride per litre for lunch while the control group received standard milk. The double-blind intervention lasted for 21 months (weekdays) and data were collected through clinical examinations and questionnaires. The primary outcome was caries increment and secondary outcomes were measures of general health. The dropout rate was 25%. The mean baseline caries experience was 0.5 dmfs in the intervention units and 0.6 in the control units and after 21 months 0.9 and 2.2 (p < 0.05). The number of days with sick leave was similar in both groups but the children of the intervention units displayed 60% fewer days with antibiotic therapy (mean 1.9 vs. 4.7 days) and 50% less days with otitis media (0.5 vs. 1.0) (p > 0.05). In children who had participated during the whole 21-month intervention, fewer days with otitis media were reported (0.4 vs. 1.3 days, p < 0.05). No serious side effects were reported. It is concluded that daily consumption of milk containing probiotic bacteria and fluoride reduced caries in preschool children with a prevented fraction of 75%. Additional beneficial health effects were evident.

Caries-Preventive Effectiveness of a Fluoride Varnish: A Randomized Controlled Trial in Adolescents with Fixed Orthodontic Appliances

The aim was to evaluate the efficacy of topical fluoride varnish applications on white spot lesion (WSL) formation in adolescents during treatment with fixed orthodontic appliances. The study design was a double-blinded randomized placebo-controlled trial with two parallel arms. The subjects were 273 consecutive 12- to 15-year-old children referred for maxillary treatment with fixed orthodontic appliances. The patients were randomly assigned to a test or a control group with topical applications of either a fluoride varnish (Fluor Protector) or a placebo varnish every 6th week during the treatment period. The outcome measures at debonding were incidence and progression of WSL on the upper incisors, cuspids and premolars as scored from digital photographs by 2 independent examiners. The attrition rate was 5%. The mean number of varnish applications was 10 (range 4-20) in both groups. The incidence of WSL during the treatment with fixed appliances was 7.4% in the fluoride varnish compared to 25.3% placebo group (p < 0.001). The mean progression score was significantly lower in the fluoride varnish group than in the placebo group, 0.8 +/- 2.0 vs. 2.6 +/- 2.8 (p < 0.001). The absolute risk reduction was 18% and the number needed to treat was calculated to 5.5. The results from the present study strongly suggest that regular topical fluoride varnish applications during treatment with fixed appliances may reduce the development of WSL adjacent to the bracket base. Application of fluoride varnish should be advocated as a routine measure in orthodontic practice.

Effect of chewing gums containing xylitol or probiotic bacteria on salivary mutans streptococci and lactobacilli

The aim was to evaluate the effect of xylitol and probiotic chewing gums on salivary mutans streptococci (MS) and lactobacilli (LB). The material consisted of 80 healthy young adults (21-24 years) who volunteered after informed consent. They were assigned by random into one of four parallel study groups: A, probiotic gum group; B, xylitol gum group; C, probiotic + xylitol gum group; and D, placebo gum group. The gums were taken three times daily after meals, and the intervention period was 3 weeks. The probiotic gums contained two strains of Lactobacilli reuteri (ATCC 55730 at a dose of 1 x 10(8) CFU/gum and ATCC PTA 5289 at a dose of 1 x 10(8) CFU/gum), and each pellet of the xylitol gum contained approximately 1.0 g xylitol as single sweetener. Pretreatment and posttreatment samples of stimulated whole saliva were collected and quantified for MS and LB with chair-side kits. A statistically significant reduction (p < 0.05) of salivary MS was displayed in group A and B after the intervention when compared with baseline. A similar but nonsignificant tendency was seen in group C. No alterations of salivary LB was demonstrated in any group. In conclusion, daily chewing on gums containing probiotic bacteria or xylitol reduced the levels of salivary MS in a significant way. However, a combination of probiotic and xylitol gums did not seem to enhance this effect.

Caries in 4-year-old children after maternal chewing of gums containing combinations of xylitol, sorbitol, chlorhexidine and fluoride

AIM

To evaluate the effect of maternal use of chewing gums containing combinations of xylitol, sorbitol, chlorhexidine and fluoride on caries prevalence in a group of mother's 4-year-old children.

STUDY DESIGN

Randomised controlled trial.

METHODS

After screening 416 women with newborn babies, 173 mothers with high counts of salivary mutans streptococci (MS) were randomly assigned into three experimental chewing gum groups containing A) xylitol (n=61), B) chlorhexidine/xylitol/sorbitol (n=55), and C) sodium fluoride/xylitol/sorbitol (n=57). The intervention started when each child was 6 months old, was terminated one year later. All of the mothers were instructed to chew one piece of the appropriate gum for 5 minutes, three times a day. The outcome measure was the presence of cavitated and non-cavitated (enamel) lesions in the primary dentitions of the children at the age of 4 years.

RESULTS

The drop-out rate in the experimental groups was 15-20%. The mean defs, on examination at aged 4 years was 0.4 +/-1.0 in group A, 0.7 +/-1.7 in group B and 1.4 +/-3.0 in group C. The difference between group A and C was statistically significant (p<0.05).

CONCLUSIONS

Less caries was observed in children of mothers who chewed gums with xylitol as the single sweetener during the time of eruption of the first primary teeth compared with those who used gums containing fluoride, sorbitol and lower amounts of xylitol.

Xylitol concentration in saliva and dental plaque after use of various xylitol-containing products

The study consisted of two sets of experiments, one in saliva and one in dental plaque. The xylitol concentration in saliva was determined enzymatically in 12 children (mean age 11.5 years) after a standardised use of various xylitol products: (A) chewing gums (1.3 g xylitol), (B) sucking tablets (0.8 g xylitol), (C) candy tablets (1.1 g xylitol), (D) toothpaste (0.1 g xylitol), (E) rinse (1.0 g xylitol), and (F) a non-xylitol paraffin. Unstimulated saliva was sampled 1, 3, 8, 16 and 30 min after use. The concentration in dental plaque was determined after mouthrinses with contrasting amounts of xylitol (LX = 2.0 g, HX = 6.0 g, and control) and supragingival plaque was collected and pooled after 5, 15 and 30 min. The mean xylitol concentration in saliva at baseline was approximately 0.1 mg/ml. All xylitol-containing products resulted in significantly increased levels (p < 0.05) immediately after intake and remained elevated for 8-16 min in the different groups. The highest mean value in saliva was obtained immediately after use of chewing gums (33.7 +/- 16.4 mg/ml) and the lowest was demonstrated after using toothpaste (8.2 +/- 4.9 mg/ml). No significant differences were demonstrated between chewing gums (A), sucking tablets (B), candy (C) and rinses (E). In dental plaque, the mean values were 8.6 +/- 5.4 and 5.1 +/- 4.0 mg/ml 5 min after HX and LX rinses. Concerning the higher concentration, the values remained significantly elevated (p < 0.05) during the entire 30-min follow-up. In conclusion, commonly advocated xylitol-containing products gave elevated concentrations of xylitol in unstimulated whole saliva and dental plaque for at least 8 min after intake.

Inhibition of enamel lesion formation by fluoridated milk assessed by laser fluorescence--an in vitro study

The aim of this study was to investigate the effect of fluoridated milk on enamel lesion formation as assessed by laser fluorescence (LF). The material consisted of 18 extracted premolar teeth that were cut in mesial-distal direction and pairwise assigned to either test or control samples in an experimental caries model. The teeth were exposed to a low-pH 5% cellulose gel for 4 h, 5 days per week immediately followed by a 4-h period in either fluoridated (5 ppm, test) or nonfluoridated milk (control). In the meantime, the specimens were stored in pooled human-stimulated whole saliva in room temperature. All teeth were examined by visual inspection with a magnifying glass and by LF readings (DIAGNOdent) at baseline and after 2 and 4 weeks. The baseline LF readings ranged from 3 to 7 with a mean value of 5.6+/-0.9. The mean values increased with time in both groups but the increase was more marked in the control teeth, 8.7+/-2.3 vs 12.8+/-3.3 after 4 weeks, this difference being statistically significant (p<0.01). The visual examination could not distinguish between the test or control samples after 2 and 4 weeks, respectively. The findings indicated that fluoride added to milk may to some extent counteract enamel lesion formation as assessed by LF in an experimental caries model.

Fluoride concentration in saliva after consumption of a dinner meal prepared with fluoridated salt

The aim was to determine the fluoride concentration in saliva after intake of a dinner meal prepared with fluoridated salt. The investigation had a randomized cross-over design, and 10 healthy adolescents with natural fluoride content (1.06 ppm) in their drinking water participated after informed consent. After a run-in week, the subjects were served a standardized dinner of spaghetti with minced meat sauce prepared with either fluoridated salt (test arm) or non-fluoridated salt (control arm). The fluoride concentration of the test salt was 250 ppm. Samples of stimulated whole saliva was collected at baseline, directly after eating (0 min) and then after 10, 30 and 180 min. After a 1-week wash-out period, the experimental procedure was repeated with the opposite salt. Fluoride concentration in saliva was measured with a fluoride-specific electrode and the post-ingestion levels were compared with baseline using repeated-measures ANOVA. The mean baseline concentrations were 10.9 and 8.0 microg/l in the test and control arms, respectively. Immediately after the intake, the mean fluoride values increased significantly to 81.6 microg/l in the test arm and to 31.5 microg/l in the control arm (p<0.05). The fluoride levels remained elevated (p<0.05) for 30 min after ingestion of the test meal but not following the control meal. In conclusion, consumption of a dinner meal prepared with fluoridated salt increased the salivary fluoride levels for about 30 min.

Eating habits, smoking and toothbrushing in relation to dental caries: a 3-year study in Swedish female teenagers

OBJECTIVES

The aims of the present study were to describe eating, toothbrushing and smoking habits in a cohort of Swedish female adolescents, and to relate the findings to dental caries increment.

DESIGN

The research took the form of a longitudinal study.

SUBJECTS AND METHODS

The study sample consisted of a cohort of 162 girls under regular dental care, aged 12 years at baseline, who were followed for 3 years, from the sixth to the ninth grade. Eating, oral cleaning and smoking habits were self-reported three times per year through a questionnaire, and caries data at baseline and after 3 years were collected from dental records.

RESULTS

The results showed significantly (P < 0.05) impaired eating habits during the study period and that adherence to regular main meals diminished. In the eighth grade, one-third of the girls skipped breakfast before school and only 50% had their free school lunch daily. The omission of breakfast and irregular main meals, as well as smoking were significantly associated with caries (decayed, missed and filled surfaces) increment in the eighth grade (odds ratio = 4.1-4.9, P < 0.05). Snacks, light meals, soft drinks and sweets were already frequently consumed at baseline and continued to be so over the years. Although > 95% of subjects reported that they brushed their teeth at least once a day, approximately 20% did not do it every evening, and this figure remained stable over the study period. However, snacks, soft drinks and sweets, and toothbrushing habits had no significant influence on caries development.

CONCLUSION

Dietary advice for caries prevention in adolescent girls should focus on the importance of retaining regular main meals, and especially, not skipping breakfast.

Caries risk assessment as a predictor of metabolic control in young Type 1 diabetics

AIMS

To investigate the relationship between caries risk and glucosylated haemoglobin and to evaluate the use of a computerized caries risk assessment program as a predictor of metabolic control in schoolchildren with Type 1 diabetes mellitus.

METHODS

The material consisted of 64 young Type 1 diabetes mellitus patients (8-16 years) attending an outpatient paediatric clinic. Within 2 weeks after the onset of diabetes, a caries risk assessment was carried out with the aid of a computer-based program (Cariogram) and data on the level of metabolic control were collected from the medical records at the 3-year check-up. Caries increment was registered at recall clinical examinations.

RESULTS

A statistically significant positive relationship between caries risk and metabolic control was found (r = 0.51; P < 0.01), with a sevenfold increased risk of impaired metabolic control after 3 years in those assessed with high caries risk at onset (OR 7.3; P < 0.01). When the Cariogram was used as a predictor for the metabolic state of the disease, the sensitivity and specificity was 75% and 71%, respectively. The negative predictive value was 91%.

CONCLUSIONS

Our data suggested that a caries risk assessment at the diagnosis of diabetes mellitus in children may be a good indicator of overall health care that can provide useful prognostic information on the level of metabolic control after 3 years.

Effects of furosemide and bendroflumethiazide on saliva flow rate and composition

Aim of this study was to evaluate the effect on saliva flow rate and composition and on perceived xerostomia. The study used a Latin square design, all subjects being once daily (at 7.00 a.m.) taking the bendroflumethiazide (2.5 mg), furosemide (40 mg), or placebo, in a randomised order. Each treatment period of 7 days was separated by wash-out periods of 14 days. Unstimulated and paraffin chewing stimulated whole saliva, and 3% citric acid stimulated parotid and submandibular-sublingual secretion were collected twice daily, at 7.30 a.m., with the patients in a fasting condition (morning values), and at 10.30 a.m., about 2 h after intake of a standard breakfast (lunchtime values), on day 0 (baseline), day 1 (acute treatment), and day 7 (chronic treatment). Saliva flow rates were measured and all four secretions were analysed for the concentration of sodium, potassium, chloride, and total protein. Xerostomia was assessed by means of a Visual Analogue Scale. Statistical analysis used the Wilcoxon signed rank test. For flow rate, only that of submandibular-sublingual secretion was affected, significantly so in the morning during chronic treatment with both drugs. In resting whole saliva the output of both sodium and chloride tended to decrease especially during treatment with bendroflumethiazide, while in submandibular-sublingual secretion the output of all the electrolytes was decreased, especially for potassium and chloride and during treatment with furosemide. Further, xerostomia tended to increase during treatment with furosemide, statistically significant at lunchtime during chronic treatment. In conclusion, this study has demonstrated a modest effect on salivary flow rate and a more pronounced effect on saliva composition, especially in submandibular-sublingual secretion during treatment of healthy volunteers with therapeutic doses of two different diuretics, encouraging clinical studies in hypertensive patients and basic research as to the presence of a thiazide sensitive Na-Cl cotransporter in human salivary glands.

Fluoride levels in saliva and dental plaque after consumption of snacks prepared with fluoridated salt

AIM

To determine the concentration of fluoride in saliva and supragingival dental plaque at designated time intervals after consumption of snacks prepared with a standardised amount of fluoridated salt.

STUDY DESIGN

The investigation had a single blind prospective crossover design.

METHODS

A group of 11 healthy young adults volunteered to participate after verbal and written information and consent. After a 1-week fluoride depletion period, the subjects consumed popcorn prepared with either fluoridated (250 mg/kg) or non-fluoridated salt during 30 minutes. Unstimulated whole saliva and samples of supragingival plaque were collected before consumption (baseline) and at 30, 60 and 120 minutes after the intake. Fluoride concentration was determined with a fluoride-specific electrode and the post-ingestion levels were compared with baseline by ANOVA.

RESULTS

In saliva, the mean fluoride concentrations at baseline ranged from 0.021 to 0.027 mg/L and after the 30 minutes consumption of fluoride prepared snacks a 15-fold increase (p<0.001) was found. The same pattern was disclosed in the plaque samples. In both saliva and plaque, the fluoride levels remained significantly elevated after 2 hours (p<0.001 and p<0.05, respectively).

CONCLUSION

Consumption of snacks prepared with fluoridated table salt resulted in significantly increased fluoride levels in saliva and supragingival plaque for a period of at least two hours.

Evaluation of a computer program for caries risk assessment in schoolchildren

The 'Cariogram' is an interactive PC program for caries risk evaluation. It takes into account the interactions between caries-related factors and expresses a graphic assessment of the risk. The aim of this study was to assess the caries risk in schoolchildren using the Cariogram and to evaluate the program by comparing the caries risk assessments with the actual change in DMF. A 2-year prospective study on 446 schoolchildren, 10-11 years old, was conducted. At baseline, data on general health, diet, oral hygiene and use of fluoride were obtained. Saliva analyses included mutans streptococci and lactobacilli counts, buffer capacity and secretion rate. DMFT and DMFS were calculated from records and bitewing radiographs. Scores were entered and caries risk was assessed. Re-examination for caries was done after 2 years. The children were divided into 5 groups according to the assessed caries risk at baseline. Where the Cariogram predicted a 0-20% (high risk), 21-40%, 41-60%, 61-80% and 81-100% (low risk) chance of avoiding new lesions, 8, 35, 42, 73 and 83%, respectively, had no new lesions 2 years later. Logistic regression analyses were carried out. When the Cariogram was included, only two factors, the Cariogram (p < 0.001) and the DMFS at baseline, i.e. past caries experience (p = 0.001), turned out to be significantly associated with caries increment. The Cariogram was the most powerful explanatory variable. When the Cariogram was excluded, lactobacillus count, mutans streptococci, diet intake frequency and DMFS at baseline were significantly associated with caries increment. The Cariogram predicted caries increment more accurately than any included single-factor model. How this finding can be translated into daily practice in the best and most practical way is a matter for future research.

Prevalence of salivary Streptococcus mutans in mothers and in their preschool children

OBJECTIVES

To establish the prevalence and possible relationship of oral Streptococcus mutans colonization in mother-child pairs.

DESIGN AND SETTING

An analytical cross-sectional study was carried out at a well-baby evaluation clinic held at the Public Dental Clinic, Varberg, Sweden.

SAMPLE AND METHODS

Two hundred preschool children, 100 of which were 18 months old and the remaining 100 were 3 years old, and their mothers attended the clinic. All mothers were interviewed and their children's medical history, oral hygiene routines and dietary habits established. All children were clinically examined. The presence and level of S. mutans was estimated in the mother-child pairs with the aid of the Strip mutans chair-side test.

RESULTS

Nearly 50% of mothers exhibited high levels of salivary S. mutans, prevalence among the 18-month- and 3-year-olds was 30% and 42%, respectively. A statistically significant (P < 0.01) mother-child relationship was found; a greater presence in mothers led to a higher number of children found harbouring the bacteria. Logistic regression analysis found that high maternal S. mutans levels (P < 0.001), daily sweet intake (P < 0.01) and sugary drinks in feeding bottles (P < 0.05) were significant factors for S. mutans colonization in children. Absence of daily toothbrushing and use of feeding bottles at night failed to fit into the model. Caries prevalence (initial and manifest decayed surfaces) was significantly related to S. mutans colonization (P < 0.01).

CONCLUSION

The results support the concept of vertical transmission (mother-child), emphasizing the importance of the dietary component, and justifying a primary preventive approach with targeted action directed at mothers with high levels of S. mutans colonization.

Fluoride concentrations in saliva and dental plaque in young children after intake of fluoridated milk

This study determined fluoride (F) concentrations in whole saliva and dental plaque after intake of fluoridated milk using a randomised crossover experimental design. Eighteen healthy children (6-8 years) were subjected to each of four different 3-day drinking regimens: (a) 200 ml F-free tap water; (b) 200 ml tap water with 1.0 mg F; (c) 200 ml standard milk, and (d) 200 ml standard milk with 1.0 mg F. A washout period of 7 days was organised between the different drinking regimens. All children used F-free toothpaste prior to and during the trial and were instructed to avoid F-rich food and drinks. F concentration in unstimulated whole saliva was determined at baseline and after 15 and 120 min and in plaque samples at baseline and after 2 h. The mean baseline values ranged from 0.01 to 0.02 mg F/l in saliva and between 10.4 and 14.2 mg F/l in dental plaque. A statistically significant (p < 0.05) increase of F was disclosed in saliva 15 min after drinking F-containing milk and water (0.052 and 0.058 mg F/l, respectively). After 2 h, the salivary F(-) concentrations were back to baseline values. In the plaque, however, a statistically significant (p < 0.01) twofold increase was found at 2 h after the intake of fluoridated milk and water, respectively. The results indicate that consumption of fluoridated milk contributes to a F storing process with significantly elevated F concentrations in dental plaque up to 2 h after intake. Further studies are required to determine the 'therapeutic concentration' of F in dental plaque after intake of fluoridated milk.

Caries incidence in young type 1 diabetes mellitus patients in relation to metabolic control and caries-associated risk factors

The aim of this study was to evaluate the caries incidence in a group of young patients with type 1 diabetes mellitus over a 3-year period from the onset of the disease in relation to metabolic control and to caries-associated risk factors. Sixty-four children and adolescents (8-15 years of age) had their diabetes treated and monitored according to a standard medical protocol and received extensive preventive oral health care based on individual needs. Data on blood glucose and glycosylated haemoglobin (Hb A(Ic)) were collected from the medical records. Whole saliva was collected every 3rd month and secretion rate, buffer capacity, glucose concentration, mutans streptococci and lactobacilli counts were determined. Dental examinations, including radiographs, were carried out once a year. Patients with less good metabolic control (>8.0% Hb A(Ic)) exhibited higher glucose levels in resting saliva (p < 0.05) and a significantly higher caries incidence (p < 0.05) compared to those with good metabolic control. The most influential determinants for high caries development during the 3-year follow-up period were metabolic control (odds ratio, OR = 5.7), poor oral hygiene (OR = 6.5), previous caries experience (OR = 5.3) and high levels of salivary lactobacilli (OR = 5.0). The findings suggest that the level of metabolic control and traditional caries risk markers are important factors for caries development in children and adolescents with type 1 diabetes mellitus.

Application of quantitative light-induced fluorescence to monitor incipient lesions in caries-active children. A comparative study of remineralisation by fluoride varnish and professional cleaning

The aim of this study was to apply the quantitative light-induced fluorescence (QLF) method in a randomised controlled study, comparing treatment with fluoride varnish and professional tooth cleaning for remineralisation of white spot lesions in caries-active adolescents. In the fluoride varnish group (n = 13; 32 lesions), professional tooth-cleaning was followed by application of fluoride varnish at the beginning of the study, after 1 wk, and then once every 6 wk for 6 months. The other group (n = 18; 30 lesions) underwent professional tooth-cleaning once every 6 wk for 6 months. Enamel fluorescence was measured at baseline and at each visit. In the fluoride varnish group there was a significant change over time (baseline: 6 months) for both lesion area: and average change in fluorescence (decreased lesion area and increased fluorescence radiance). The corresponding changes in the professional tooth-cleaning group were not significant. There was a significant difference in average change in fluorescence between the two test groups. For lesion area, there was no significant difference, but a tendency towards a difference between the test groups. It was concluded that (a) the QLF method is a sensitive method, suitable for longitudinal quantification of incipient caries lesions on smooth surfaces; and (b) that repeated fluoride applications had a favourable effect on the remineralisation of white spot lesions as measured after 6 months.

Effect of an antibacterial varnish on lactic acid production in plaque adjacent to fixed orthodontic appliances

The effect of an antibacterial varnish on lactic acid concentration in suspensions of early supragingival plaque collected adjacent to fixed orthodontic brackets was evaluated in 25 adolescents using a double-blind split-mouth design with a placebo varnish control. The test varnish contained 1% chlorhexidine and 1% thymol as active ingredients. Both varnishes were applied on two occasions within 3 days and plaque was subsequently collected at 3, 7 and 30 days after the first treatment. The samples were evaluated for total viable counts (TVC) and the proportion of mutans streptococci. Acid fermentation in suspensions was induced by glucose and L(+)-lactic acid concentrations were determined enzymatically after a 30-min incubation period. The test varnish did not affect TVC but reduced the proportion of mutans streptococci significantly at the 7-day follow-up (P<0.05). The concentration of lactic acid was reduced by approximately 20% on the 3- and 7-day follow-ups (P<0.05). The results suggest that the chlorhexidine/thymol-containing varnish may to some extent reduce the viability and metabolic activity of susceptible oral bacteria in suspensions of early supragingival plaque.

Effect of a school-based preventive program with salivary lactobacillus counts as sugar-motivating tool on caries increment in adolescents

The caries preventive outcome of a school-based program with salivary; lactobacillus counts as sugar-motivating tool was evaluated in six cohorts of totally 936 adolescents in a comprehensive school in Sweden. Students from a neighboring district with similar socioeconomic structure but with no corresponding dental health-promoting activities were selected as reference. The program started in the beginning of the 7th grade (13 years) and was terminated at the end of the 9th grade (16 years). Salivary lactobacilli were evaluated semi-annually with a dip-slide method and used for individual counseling. Dental caries was scored from the dental records and bitewing radiographs of each 4th participant at baseline and at 16 and 19 years of age. The number of salivary lactobacilli decreased significantly (P< 0.05) in all cohorts but one during the program. There was no significant difference in the increment of caries (DFS) between the participants from the study and reference schools, either at the end of the program or at 19 years of age. The increment of proximal enamel caries was slightly lower in the study group compared with the reference group (P< 0.05) at the final registration. Considering the time and efforts spent, the results did not seem to justify a school-based intervention with lactobacillus counts as a sugar-motivating tool in an adolescent low-caries population.

Comparison of the efficacy of three different chlorhexidine preparations in decreasing the levels of mutans streptococci in saliva and interdental plaque

The aim of the present study was to evaluate and compare the effects of three different chlorhexidine (CHX)-containing preparations on mutans streptococci (MS) levels in interdental plaque and whole saliva. Ninety-three healthy school-children (8-10 years old) with high scores of salivary MS were selected by a screening procedure and randomised into three equally sized groups. MS were enumerated at all mesial interdental sites of the first permanent molars with aid of a modified chairside technique. The patients were then treated three times within 2 weeks with either a 1% CHX/thymol-containing varnish (group A) or a 1% CHX gel (group B), or they were subjected to daily supervised toothbrushing with a 0.4% CHX dentifrice for 1 month (group C). Follow-up samples of saliva and plaque from the interdental sites were collected 1 and 3 months after termination of treatment. A statistically significant reduction of MS levels in saliva and interdental plaque was found in all groups after 1 month. The CHX-containing dentifrice (group C) was the most effective method in reducing MS levels in saliva, and a significantly stronger (p < 0.05) suppression was found after 1 and 3 months when compared with the gel and the varnish forms. The gel (group B) tended to be slightly more effective than the varnish (group A). In the interdental plaque, the reduction of MS was less marked than in the saliva, and the three groups exhibited MS reductions of similar magnitude (20%) and duration, persisting up to 3 months. However, a high proportion (approximately 50%) of all interdental sites were relatively unaffected by the treatments. In conclusion, our results suggest that the interdental MS colonisation was difficult to combat, irrespective of CHX preparation and method, while the salivary levels were more easily affected. Daily tooth-brushing with a CHX-containing dentifrice was more effective in reducing MS in saliva compared with the gel or varnish applications.

Fluoride concentration in whole saliva and separate gland secretions in schoolchildren after intake of fluoridated milk

Fluoride concentration in whole saliva and in separate gland secretions was studied after a 7-day fluoridated milk regimen (1mg F per day) in 12 healthy schoolchildren aged 10-13 years. A 2-week fluoride-free run-in period preceded the tests in order to establish the endogenous baseline levels. Unstimulated and stimulated whole saliva and stimulated parotid and submandibular-sublingual saliva were collected at 1, 3, 6, 12 and 24h after F-milk ingestion, and fluoride concentrations were determined with an ion-selective electrode. Typical time-dependent excretion curves were obtained in all collected secretions. The fluoride levels were significantly elevated 1 and 3h in whole saliva and up to 6h in the gland secretions after intake of fluoridated milk when compared to baseline values. When acid-stimulated, the submandibular-sublingual glands were the major contributors of fluoride in the oral cavity. In conclusion, the results of this study demonstrate that fluoride ingested with milk is excreted through the salivary glands, indicating that the bioavailability of fluoride from milk equals that of other vehicles.

Infant oral health

According to the United Nations' Convention on "The Rights of the Child," articles 2 and 24, all children should have the same rights and have right to health and medical service. Early childhood caries is a lifestyle disease with biologic, behavioral, and social determinants. An early screening of all children at around 1 year of age is an excellent opportunity for early detection of risk factors and risk indicators that may increase the possibilities for its prevention. The caries risk evaluation should form the base for appropriate recommendations of preventive measures. The preventive care must be coordinated with an eventual operative care and should be based on education of prospective and new parents as well as professional and home-based measures. The various interventions must be developed further and evaluated in prospective studies in terms of effectiveness and efficiency for this specific age group. This is an urgent task for dental professionals and all societies with the ambition of providing good dental care for all young children.