Caries risk profiles of 12-13-year-old children in Laos and Sweden.

PURPOSE: To analyse caries risk factors of 12-13-year-old children living in Laos, using the computer program Cariogram to illustrate the caries risk profile. In addition, to compare the results with a study performed in Sweden. MATERIALS AND METHODS: One hundred Laotian and 392 Swedish children were included. Interviews were performed to obtain information on diet intake and fluoride use. Saliva was analysed for mutans streptococci, lactobacilli and secretion rate/buffering capacity. Oral hygiene was assessed using the Silness and Löe criteria. Caries prevalence was recorded according to WHO. The data were entered into the Cariogram to determine each child's caries risk, expressed as 'the chance of avoiding caries'. The children were divided into five risk groups. RESULTS: Mean DMFT level of the Laotian children was 4.61 +/- 2.95 and 1.38 +/- 1.97 in the Swedish group. For the risk factors plaque amount, frequency of food intake, saliva secretion rate, buffering capacity and fluoride, the Laotian children had significantly less favourable values compared to the Swedes. Only 6% of Laotian children belonged to the Cariogram low risk group versus 40% of the Swedish children. The mean DMFT for the five Cariogram groups was (from low to high risk) 0.00, 3.00, 3.56, 5.66, 6.11 for the Lao children and 0.31, 1.39, 2.56, 3.03, 2.91 for the Swedish ones. The mean chance of avoiding caries was 37.3% for the Laotians and 69.2% for the Swedish children (p < 0.001). CONCLUSION: According to the 'opinion' of the Cariogram, the Laotian children demonstrated significantly higher caries risk than Swedish children.

A new method for the estimation of mutans streptococci in human saliva.

A new method for quantitating the numbers of mutans streptococci in saliva--the "Strip mutans" test--was developed. It includes the following steps: A prepared plastic spatula is contaminated with saliva, transferred to a selective broth, incubated for two days, and dried. A predetermined area is counted or evaluated for CFUs of mutans streptococci. The medium contains sucrose to promote adhesion of mutans streptococci to the strip. Bacitracin, added just before use, is the basis for the selectivity. Results with the new medium were compared with those from the "spatula technique" and with those from conventional saliva sampling with dilution. The studies involved 302 and 60 schoolchildren, respectively. There was a highly significant correlation between the results from the new method and those from conventional methods. The strip mutans test is easy to used and has long shelf-life, and the spatulas with adherent colonies can be saved for future comparisons.

Streptococcus mutans serotypes: some aspects of their identification, distribution, antigenic shifts, and relationship to caries.

For an immunologic point of view, several facts are worth consideration. S mutans can be separated into at least seven serotypes. Five of the types are based on antigens that may be specific for S mutans. One type, e, is related to the Lancefield group E streptocci, and one type, f, may lack an antigen that shows serological specificity. Analyses of plaque samples from individuals with a high caries activity have, in most instances, shown the presence of c, d, and possibly the g types. This does not necessarily mean that they are per se more cariogenic than the other types, but if all the serotypes cannot be combatted simultaneously, the c, d, and g types are an obvious first choice. S mutans strains do have antigens other than those used for serological identification, and it is not known which antigens can evoke antibodies with the highest protective capacity in humans. The phenomenon of antigenic shifts may make it possible for the bacteria to elude antibodies. However, the number of possible changes may be restricted. If certain antigens are of importance for the cariogenicity of S mutans, a change in their structure might result in a less cariogenic flora.

A 30-month longitudinal study of the effects of some oral hygiene measures on Streptococcus mutans and approximal dental caries.

The effects of some oral hygiene measures on Streptococcus mutants and approximal dental caries were evaluated. One hundred and eighty-seven 13-year-old individuals with high levels of salivary S. mutans (greater than 10(6)/mL) were selected. They were randomly distributed into three groups. Group I initially received professional mechanical tooth-cleaning, tongue-scraping, chlorhexidine treatment, and oral hygiene instructions concentrated on the approximal surfaces most colonized by S. mutans. The treatment was given four times with intervals of two days, followed by one single treatment every six months throughout the experimental period. The initial treatment period for group II, also consisting of four visits, included the same oral hygiene instructions as for group I. The instructions were repeated every six months. Group III was maintained in the preventive program provided by the local Dental Health Office, based on mechanical plaque control and topical use of fluorides and chlorhexidine at individualized intervals. Group I showed a significant immediate reduction of S. mutans in saliva as well as an approximal tooth surfaces. After six months, there were no differences among the three groups regarding these variables. Compared with baseline, there was a significant reduction of S. mutans in all groups. There was no significant difference in caries progression among the three groups. However, the selected "high-risk" individuals in group I developed 0.25 new manifest caries lesions approximally/year, compared with 0.27 for all children of the same age group in the area. Seventeen individuals had approximal surfaces with consistently high or consistently low S. mutans levels. Forty-six percent of the surfaces with high values developed new or progressive caries, compared with 2% of the surfaces with low values.

Mutans streptococci, oral hygiene, and caries in an adult Swedish population.

The objective of the present study was to describe the distribution of salivary mutans streptococci in a randomly selected adult population and to relate the distribution to the prevalence of caries. The aim was also to study the association between caries and different levels of oral hygiene (OH). The results were based on the assessment of caries, dental plaque, and concentration of salivary mutans streptococci in 914 subjects who represented 95% of an age- and gender-stratified population sample of 967 individuals, randomly selected from the total adult population living in Alvsborg County, Sweden. The results showed that the distribution of mutans streptococci among dentate adults not wearing any kind of removable denture(s) was similar to that previously reported from studies on Swedish schoolchildren, while a comparably higher proportion of subjects with high levels of mutans streptococci was found among the dentate individuals wearing some kind of removable denture(s). Even higher proportions were found among edentulous individuals with complete denture(s). There was a correlation between mutans streptococci concentration in saliva and caries. The subjects with lower concentrations showed a significantly lower mean number of decayed surfaces, compared with the individuals with higher concentrations of mutans streptococci in their saliva. The median OH standard was lower in the older age groups, and there was a higher ratio of decayed surfaces per remaining tooth in those age groups, in comparison with the younger groups. However, for individuals without mutans streptococci, no relation between OH standard and caries could be found and, regardless of OH standard, higher numbers of decayed surfaces were found with an increasing concentration of mutans streptococci in saliva.

Detection of antigens in enzymic lysates of cell wall from Streptococcus mutans strains.

Lysis of cell wall preparations from strains representing serotypes a - g of Streptococcus mutans has provided a convenient and efficient means of obtaining the typing antigens in a soluble undegraded form, and has demonstrated that, in each case, the antigen is a cell wall component in the strict sense of a component joined covalently to peptidoglycan. This influences the choice of extraction procedures.

The more Streptococcus mutans, the more caries on approximal surfaces.

The relationship between the presence of Streptococcus mutans and caries on approximal tooth surfaces was studied in a group of 28 children who were 13 years old at baseline. 700 surfaces in the pre-molar and molar region were studied. Sampling of S. mutans was performed with a toothpick method at the beginning of the study and after one and two years. From bite-wing radiographs, the approximal surfaces were recorded as caries-free, decayed, or restored. Progression of lesions during the two years was also studied. More new caries lesions and progression caries lesions were found on surfaces positive for S. mutans than on surfaces without, and the more S. mutans, the more lesions, 52% of the surfaces with positive S. mutans findings at all three sampling occasions became carious or had caries in a progressive form. Among the surfaces with no detectable S. mutans, the corresponding figure was 8%. 80 out of the 530 surfaces diagnosed as intact at the start of the study became carious over the two-year period. 69 of these were S. mutans-positive at the first and/or second sampling.

Frequency of the bacterium Streptococcus mutans in the saliva of selected human populations.

Stimulated saliva was transported from the mouth to a selective substrate, MSB-agar, with a wooden spatula. School children, aged 7-15, military recruits, aged 19-21, and a group of refugees from Vietnam were investigated. 10-15 per cent, in one exceptional case 35 per cent of the sampled school children had no detectable Strep. mutans, whereas about 20 per cent had very high numbers. The recruits were slightly more infected, and the refugees heavily infected. High numbers of Strep. mutans in saliva indicate a high-caries risk.

Preventive measures in mothers influence the establishment of the bacterium Streptococcus mutans in their infants.

First-time mothers who had a high salivary number of Strep. mutans [greater than or equal to 10(6) colony-forming-units (c.f.u.) per ml] were selected. Every second mother was given a special preventive programme to reduce her salivary level below 3 x 10(5) c.f.u. per ml. Where a reduction of Strep. mutans was achieved in the mother, the establishment of Strep. mutans in her infant was prevented or delayed. Thus, 28 mothers were successfully treated until their infants were 23 months old and only 3 of their infants (11 per cent) were infected with Strep. mutans, compared with 17 out of 38 infants in the control group (45 per cent). In both groups, the percentage of infected infants increased with increasing age, although at all ages fewer infants were infected with Strep. mutans in the test group than in the control group. Sixteen infants of successfully treated mothers had reached the age of 36 months. Three were infected (19 per cent) compared with 17 out of 27 in the control group (63 per cent). These findings show that the spread of Strep. mutans can be delayed or prevented by measures directed against the main source of infection, an approach which is successful in the prevention of other infectious diseases.

The relationship between the bacterium Streptococcus mutans in the saliva and dental caries in children in Mozambique.

Four hundred and sixty-two children, aged 10-14 years, from eight areas were examined for Streptococcus mutans in saliva and for dental caries. Strep. mutans strains from some samples were further characterized by serological and biochemical methods. Strep. mutans was identified in 98 per cent of the children and 40 per cent showed high counts. Serotypes c and d dominated among the strains. The distribution of Strep. mutans among the children varied between the eight areas but was not correlated with the difference in caries prevalence which ranged from 38 to 88 per cent. In individual children, however, there was an association between high counts of Strep. mutans and the presence of dental caries. Thus, Strep. mutans can be widely distributed and occurs in high numbers in a population with a low prevalence of caries.

beta 2-Microglobulin in saliva and its relation to flow rate in different glands in man.

The concentration of beta 2-microglobulin (beta 2-m) in parotid saliva and sera from 13 adult hypogammaglobulinaemic subjects and in parotid saliva from 7 normal adults was determined by radioimmunoassay. Parotid and submandibular/sublingual saliva was collected from four normal and one hypogammaglobulinaemic subject in unstimulated and stimulated samples, and concentrations of IgA and beta 2-m were determined. The beta 2-m concentration in parotid saliva from hypogammaglobulinaemic subjects was 0.50 mg/l (0.2-1.1) and in normal adults 0.41 mg/l (0.2-0.9). In parotid saliva, the concentration of beta 2-m was negatively correlated with the flow rate, whereas in submandibular/sublingual a positive correlation was seen. Serum levels of beta 2-m in hypogammaglobulinaemic subjects were within the normal range of healthy adults. Gel filtration of saliva separated beta 2-m from IgA and from high molecular weight agglutinins. Beta 2-m was eluted as one single peak.

Daucus carrota (carrot)--a selective bacteriosorbent.

1) An extract of D. carrota induces agglutination of most serotypes of S. mutans but not of S. salivarius or S. mitis. 2) If added to a suspension of mixed bacteria, a piece of D. carrota may selectively sorb S. mutans while S. salivarius and S. mitis only are affected to a minor degree. 3) A saliva coat on the bacteria may reduce the uptake of S. mutans to D. carota but does not totally prevent it.

Antibodies reacting with Streptococcus mutans in secretions from minor salivary glands in humans.

1) Antibodies reacting with S. mutans in secretions from minor salivary glands in humans were determined by a modified Enzyme Linked Immunosorbent Assay. 2) IgA antibodies reacting with S. mutans serotype c were found in all samples examined. 3) The antibody level in the secretions of the minor salivary glands varied considerably between different subjects and was considerably higher than that of parotid saliva. 4) A variation in antibody concentration over time was observed in some individuals. 5) Topical application of a streptococcal vaccine consisting of formalin killed cells increased the level of antibodies in the secretions of one person. In two persons no effect was observed.

Effects of glass ionomer cement, resin-based pit and fissure sealant and HF applications on occlusal caries in a developing country field trial.

The aim of this community-oriented study was to evaluate different methods to prevent fissure caries. The following products and measures were tested: 1) glass ionomer cement (GIC) applied by dentist; 2) same material applied by short term (3 days) trained personnel (teachers); 3) application of a 0.5% HF solution three times; 4) an established autopolymerized resin based sealant (Delton). The study was performed in Bangkok, Thailand, a city in a developing country experiencing increasing caries prevalence. Children with at least three sound permanent molars from two age groups, 7-8 and 12-13-yr-olds respectively were chosen from very low to medium socioeconomic level families. 1264 children were systematically assigned to experiment or control groups based on school and DMFT. For the younger age group, the 2 yr mean DFS occlusal increment in the Control group was 0.66 surfaces. Significantly lower increments were observed in the GIC experimental group: 0.17 surfaces applied by the teachers and 0.32 applied by dentist, corresponding to 74% and 52% reductions, respectively. The mean increment in the HF group was 0.44 surfaces, a 33% reduction in relation to the Control group. For the 12-13-yr-olds, the mean occlusal surface DF increment was 0.70 surfaces in the Control group. Almost no occlusal increment was found in the Delton group, 0.05 DFS, a 93% reduction. In the GIC Dentist group, the DFS increment was 0.48 and in the Teacher group 0.56, corresponding to 31% and 20% reduction, respectively. A slight and nonsignificant increase of caries in relation to the Control group was observed in the HF group.(ABSTRACT TRUNCATED AT 250 WORDS)

Streptococcus mutans and dental caries in urban and rural schoolchildren in Thailand.

Two groups of Thai schoolchildren aged 11-13 yr were examined for dental caries, dental fluorosis and Streptococcus mutans. One hundred children lived in an urban district, Bangkok, and 71 children in a rural district, Petchaboon. Saliva samples were analyzed for S. mutans by the spatula method. The fluoride content of the drinking waters was also determined. The prevalence of caries, diagnosed according to WHO, was 89% in Bangkok and 18% in the rural district. Mean DMFT was 3.46 and 0.38 respectively. S. mutans was found in 98% of the urban children and in 82% of the rural. The differences in distribution between S. mutans and DMFT classes were statistically significant for the total sample. Mild fluorosis was present in some of the rural children.

Caries prevalence, salivary Streptococcus mutans and dietary scores in 13-year-old Swedish schoolchildren.

388 13-yr-old schoolchildren from Karlstad, Sweden, participated. Dental caries experience was expressed as number of decayed (D) and filled (F) tooth surfaces (S), and registered on bite-wing radiographs and obtained from records. Salivary Streptococcus mutans counts were determined by a spatula method. A dietary score was calculated for each individual based on an interview concerning the intake frequency of 23 sugar-containing products. Significantly lower DFS values were found in the group with no detectable S. mutans compared to three of the four groups with salivary S. mutans (P less than 0.01). No differences were found between the DFS values of individuals with high, moderate or low dietary scores. There was no statistically significant association between dietary scores and levels of S. mutans. Among the children with no detectable S. mutans, there were higher DFS-values with increasing intake frequency. No relationship between initial caries lesions, S. mutans and diet was found.

Oral health and factors related to oral health in Polish schoolchildren.

The oral health and factors related to oral health were surveyed in 168 schoolchildren, aged 10-12 years, attending one school in Warsaw. The children were examined for dental caries and gingival status, dental plaque and salivary Streptococcus mutans and Lactobacillus counts. An interview on dietary habits and use of fluoridated toothpaste was also performed. The results showed a mean DMFT of 4.7 in the sample. Gingival Index 1 and Plaque Index 3 were median scores for the majority of the children. S. mutans was demonstrated in 94% of the children and high numbers were found in 15%. Lactobacillus sp. were present in all examined children, with high counts in 56% of the subjects. The interview revealed that most of the children eat five or six times per day and consume candies or cakes each day. Fluoridated toothpaste was not used regularly by any of the children. In conclusion this study shows a high prevalence of dental disease and an unfavorable combination of etiologic factors.

Effect of a preventive program on dental caries and mutans streptococci in Polish schoolchildren.

The effect of a preventive program was studied in Polish schoolchildren. The study was carried out in a group of 133 children, aged 10-12 yr, divided into a test and a control group. Children in the test group were initially treated with temporary restorations and were then given oral health education and preventive treatment by a specially trained chairside assistant. The preventive treatment included prophylaxis and topical fluoride treatment and was carried out at least 10 times a year. The mean 3-yr DFS increment was 1.7 in the test and 10.9 in the control group. The salivary counts of mutans streptococci were similar in test and control group at baseline and after 1 and 2 yr. At the examination after 3 yr, a difference was established between the two groups.

Introducing the Significant Caries Index together with a proposal for a new global oral health goal for 12-year-olds.

AIM: To describe a new index, the 'Significant Caries Index' (SiC Index) with the intention of focusing attention on those individuals with the highest caries scores in each population. METHOD: Attention is drawn to the skewed distribution of dental caries within a given population, indicating that there are still large groups of individuals who have considerably more caries than the WHO/FDI target level of DMFT 3 by the year 2000. The index is calculated as follows: individuals are sorted according to their DMFT values. The one third of the population with the highest caries score is selected and the mean DMFT for this subgroup is calculated. This value constitutes the SiC Index. RESULTS: The SiC Index can be easily calculated and used as a measure for future oral health goals. CONCLUSION: The SiC Index should be less than 3 DMFT in the 12-year-olds in a given population and it is hoped that this global oral health goal is reached at the latest by the year 2015.

The Swedish dental health programme for adults.

The Swedish dental health programme for adults provides guidelines for the prevention of caries and periodontal disease. Swedish dentists are recommended to follow the principles of the programme, which was issued by the Swedish National Board of Health and Welfare. The article describes the background, the preparation and the content of the programme.