学龄前儿童乳牙龋相关因素的分析

目的 评价学龄前儿童的唾液变形链球菌、唾液流速和缓冲力、口腔卫生状况、饮食和口腔卫生习惯、母亲文化程度和职业等因素在乳牙龋发生中的意义.方法 采用病例对照研究方法,对1018名4岁和5岁儿童进行龋齿检查,其中dmft≥6的204人构成高龋组,dmft=0的237人为无龋组.测定两组儿童唾液变形链球菌水平、唾液流速和缓冲力、软垢指数,并由儿童母亲回答统一问卷.结果 共有417名儿童纳入结果的统计中.Logistic回归分析结果显示,唾液变形链球菌(OR=3.019)、软垢指数(OR=2.263)、每天吃甜食次数(OR=1.729)、每天喝甜饮料次数(OR=1.496)、奶瓶内容物含糖(OR=2.255)等因素有意义.结论 唾液变形链球菌水平高、口腔卫生差、高频率摄入甜食、奶瓶喂养时内容物含糖是乳牙龋的重要危险因素.     

Dental caries and caries-associated microorganisms in Uruguayan preschool children

The prevalence of dental caries was studied in 3-5-year-old Uruguayan children (n = 76) living in 2 areas with different socioeconomic and cultural conditions. More children from the low socioeconomic area of Las Acacias had caries (68%) than children from the middle- to high-class neighborhood of Pocitos (19%). They also had poorer oral hygiene and a significantly higher caries prevalence (P < 0.05) than those from Pocitos. The occurrence of mutans streptococci and lactobacilli was determined in whole unstimulated saliva and compared with that in debris collected with a loop from the dorsum of the tongue. Mutans streptococci were detected in 42% of the children with significant correlations between the salivary levels of the microorganism and caries experience. Lactobacilli were recovered less frequently (18%). The detection of mutans streptococci in the tongue-loop samples was significantly correlated with that in whole saliva.     

Mutans streptococci and lactobacilli in saliva from children with insulin-dependent diabetes mellitus

The quantitative distribution of mutans streptococci and lactobacilli in saliva of insulin-dependent diabetic children was compared with a group of healthy children and related to the metabolic control of the disease. The study group, consisting of 94 boys and girls (age 4-19) with type 1 diabetes was matched by sex and age with a non-diabetic control group. Stimulated whole saliva was collected and flow rate, buffer capacity and the levels of mutans streptococci and lactobacilli were analysed in all children. In the diabetic group, total salivary proteins and glucose content of saliva were determined. Data on caries experience were recorded from the dental cards of all children. There were no difference in the distribution or number of mutans streptococci between the groups, but significantly (p less than 0.05) lower levels of lactobacilli were found among the diabetic children. The number of lactobacilli was positively correlated (p less than 0.05) to glucose concentration in saliva. There was no difference in the prevalence of caries between the groups. The present findings suggest that the dietary treatment of young insulin dependent diabetics gives rise to a reduced number of lactobacilli in saliva but does not affect the mutans streptococci.     

Mutans streptococci and lactobacilli in breast-fed children with rampant caries.

This study aimed to investigate the prevalence of selected components of the oral microflora in breast-fed children who developed rampant caries (resembling nursing caries) under hitherto unexplained circumstances. Dental plaque and saliva samples were collected from breast-fed children, aged between 1 and 2.5 years, with and without rampant caries. Mutans streptococci and lactobacilli were isolated from dental plaque of all children with rampant caries and from most caries-free children. None of the colonies of mutans streptococci resembled those of Streptococcus sobrinus. The mean counts of the mutans streptococci and lactobacilli were 100-fold higher in plaque samples from children with rampant caries as compared with caries-free children. No difference could be found between the numbers of mutans streptococci in plaque overlaying cavities and that from adjacent sound enamel. In contrast, the counts of lactobacilli in plaque were approximately 100-fold higher from cavities than from sound surfaces. The levels of mutans streptococci in saliva were directly related to the presence of rampant caries. The results show that caries-free and caries-active breast-fed children, aged 1 to 2.5 years, harbour mutans streptococci and lactobacilli on their teeth. Rampant caries in these children can occur in the absence of nursing bottles or any other feeding abuse during weaning and in the presence of an aciduric plaque microflora, as has been reported for children with nursing bottle caries.     

Dental caries and caries-associated microorganisms in Uruguayan preschool children

The prevalence of dental caries was studied in 3-5-year-old Uruguayan children (n = 76) living in 2 areas with different socioeconomic and cultural conditions. More children from the low socioeconomic area of Las Acacias had caries (68%) than children from the middle- to high-class neighborhood of Pocitos (19%). They also had poorer oral hygiene and a significantly higher caries prevalence (P &lt; 0.05) than those from Pocitos. The occurrence of mutans streptococci and lactobacilli was determined in whole unstimulated saliva and compared with that in debris collected with a loop from the dorsum of the tongue. Mutans streptococci were detected in 42% of the children with significant correlations between the salivary levels of the microorganism and caries experience. Lactobacilli were recovered less frequently (18%). The detection of mutans streptococci in the tongue-loop samples was significantly correlated with that in whole saliva.     

Relationships between socioeconomic backgrounds, caries associated microflora and caries experience in 12-year-olds in Bosnia and Herzegovina in 2004

AIM: To present the prevalence of dental caries in Bosnia and Herzegovina (BH), to estimate the levels of salivary mutans streptococci and lactobacilli and compare them with caries prevalence in 12-years-old children from different socioeconomic backgrounds. STUDY DESIGN AND METHODS: A survey was carried out in 8 cantons of the Federation of BH (FBH) and in Republic Srpska (RS) in 2004. The final sample included 560 12-year-olds. The clinical examinations focused on dental status, expressed as DMFT index, and they were carried out by one examiner, following WHO standard methodologies. Additionally, the study involved 109 12-years old children from Sarajevo, divided in three groups, based on their socioeconomic background. For measuring lactobacillus and mutans streptococci (MS) count in saliva Dentocult LB and Dentocult SM-Strip Mutans were used. Levels of MS and lactobacilli were expressed as a score between 0 and 3, indicating very low to very high levels of SM and lactobacilli. RESULTS: The average DMFT of the 12-year-olds was 4.16+/-2.92. On average, 91% of the 12-year-olds were affected with dental caries. The SiC Index was 7.41+/-3.31. Investigating the relationship between caries associated microflora and caries experience in children of different socioeconomic status showed the following: significant difference in caries prevalence was found in children with different living conditions, where children with high socioeconomic status had better oral health compared to the other two groups. For mutans streptococci, 25.7% of the children had mutans class 0, 24.8% class 1, 34.9% class 2 and 14.6% class 3. The mean DMFT for mutans class 0 was 3.50, for class 1 was 4.30, for class 2 was 5.62 and for class 3 was 6.0. For lactobacilli, 38.5% of the children had lactobacilli class 0, 25.7% class 1, 23.9% class 2 and 11.9% class 3. The mean DMFT for lactobacilli class 0 was 4.3, for class 1 was 4.9, for class 2 was 4.8 and for class 3 was 6.0. No significant differences in the level of mutans streptococci and lactobacilli were found between the groups. CONCLUSION: There is moderate caries prevalence among BH 12-year-olds (DMFT 4.16+/-2.92). Caries experience varies between children with different living condition but no relation between levels of salivary mutans streptococci and lactobacilli and socioeconomic status of children could be found.     

Mutans streptococci in saliva and dental caries in children living in a high and a low fluoride area

The aim of this study was to obtain information about the quantitative distribution of salivary mutans streptococci and the relation to dental caries in children with contrasting levels of natural water fluoride. A total of 698 schoolchildren aged 12 yr were selected from areas with high (1.2 ppm) or low (0.1 ppm) fluoride concentration in the drinking water. They were all examined for the presence and number of mutans streptococci in saliva by a specially prepared plastic strip, the "Strip mutans" method, cultivated in a selective broth. Data on the caries experience were obtained from the dental records and from bite-wing radiographs. Mutans streptococci were identified in 82% of all children with no difference between the two areas. The number of mutans streptococci was however significantly (p less than 0.05) lower among the children from the high fluoride area than those from the low fluoride area. Children with no detectable or low levels (0-10 CFU) of mutans streptococci had less caries experience than children with moderate or high levels (11- greater than 500 CFU) in both areas investigated.     

The earlier the colonization by mutans streptococci, the higher the caries prevalence at 4 years of age

Seventy-eight 4-year-old children, examined earlier for the presence of mutans streptococci at 4-month intervals from 15 months of age, were recalled for recording of dental caries and salivary sampling. The saliva samples were analysed for the presence of mutans streptococci, including the species Streptococcus mutans and Streptococcus sobrinus and lactobacilli. The results showed that the earlier the mutans streptococci had been detected in the children, the higher the caries experience. Eighty-nine percent of the children colonized at 2 years of age had experienced caries and had a mean dfs of 5.0 compared with 25% of the non-colonized 4-year-olds with a mean dfs of 0.3. S. mutans was the predominant species. S. sobrinus was usually found in combination with S. mutans , except in 2 children where S. sobrinus was the only species detected. More children with multiple species had higher numbers of total mutans streptococci and a tendency to higher caries prevalence than children with only S. mutans.     

Association of the microbial flora of dental plaque and saliva with human root-surface caries

Dental plaque was obtained from one or two sound root surfaces of subjects with different degrees of root-surface caries experience. From subjects with root-surface caries, plaque samples were also obtained from either one incipient or one more advanced lesion. Proportions of the total flora were determined for total streptococci and different streptococcal species, total and different Actinomyces species, and lactobacilli. A sample of saliva was obtained from about one-third of the subjects for determination of the concentrations of mutans streptococci and lactobacilli. The main observations were: (1) Subjects without root-surface caries or restorations (group I), as compared with subjects with root-surface caries with or without restorations (group II), were characterized by having a lower prevalence and proportion of mutans streptococci and a higher prevalence and proportion of A. naeslundii in plaque on sound root surfaces; (2) subjects in group I also tended to have a lower salivary concentration of mutans streptococci and lactobacilli than subjects in group II; (3) dental plaque on sound surfaces in group II subjects contained a lower proportion of mutans streptococci than plaque associated with incipient or advanced lesions; and (4) the prevalence and proportion of lactobacilli in plaque associated with sound as well as carious root surfaces were very low. The data reinforce findings from other studies and indicate that, as for coronal caries, the plaque and saliva populations of mutans streptococci specifically are correlated positively with the presence of root-surface caries.     

Mutans streptococci and lactobacilli in saliva after the application of fissure sealants

Because dental fissures may serve as reservoirs for mutans streptococci, preventive measures should be taken to control microbial concentrations at these sites. This study estimated the influence that sealing permanent first molars would have on the levels of mutans streptococci and lactobacilli in saliva of healthy seven-year-old schoolchildren. Permanent first molars were sealed in 31 children without caries (NC group) and in 32 children with caries (C group). None of the children had caries in their permanent first molars. Conventional methods were used to count mutans streptococci and lactobacilli in saliva before applying the sealant and again at 4 and 12 weeks after application. Baseline counts of lactobacilli and mutans streptococci were significantly higher in the C group. A significant reduction in mutans streptococci was observed in the NC group at 4 and 12 weeks. It was concluded that fissure sealants in permanent first molars can help reduce salivary levels of mutans streptococci in children without caries.     

Associations of microbiological factors and plaque index with caries prevalence and water fluoridation status

Plaque indices, numbers of mutans streptococci, lactobacilli and total viable flora in plaque and saliva were assessed as part of a large-scale cross-sectional study designed to determine the factors that are associated with high caries activity in children. Subjects, 12 to 15 years old, residing in areas where the water supplies were either fluoridated (n = 140) or fluoride-deficient (n = 173) were studied. Mutans streptococci and lactobacilli numbers in saliva were positively correlated with plaque index. Plaque indices were significantly higher in the high-caries group than in the zero-caries group of the fluoride-deficient community. In the fluoridated community, there was no difference in the plaque index between the zero- or high-caries groups. In each community, pooled dental plaque and saliva harbored fewer mutans streptococci and lactobacilli in the zero-caries than the high-caries group. Greater numbers of mutans streptococci were found in the dental plaque and saliva of the zero-caries subjects in the fluoridated community than in the fluoride-deficient community, suggesting that a greater caries challenge can coexist with zero-caries status in the fluoridated community.     

Mutans streptococci, lactobacilli and caries prevalence in 11-and 12-year-old Icelandic children

Since the caries prevalence has not declined in Iceland as it has in other European countries, it was of interest to study the presence of cariogenic bacteria in Icelandic children. The prevalence of salivary mutans streptococci and lactobacilli was examined in 217 11- and 12-yr-old Icelandic children and was related to their caries prevalence. In 2% of the children mutans streptococci were not found whereas 31% and 35% of the 11-yr-olds and 12-yr-olds respectively carried more than 10(6) CFU per ml saliva. Lactobacilli were not detected in 8% of the children whereas 28% of the 11-yr-olds and 23% of the 12-yr-olds had more than 10(5) CFU per ml saliva. The mean caries prevalence (DFS), initial caries included, for 11-yr-olds was 21.6 and for 12-yr-olds 28.8. Both mutans streptococci and lactobacilli were significantly correlated to each other as well as to caries prevalence. An increased number of these microorganisms, especially the mutans streptococci, were associated with an increased DFS. Children with high salivary counts of mutans streptococci and lactobacilli showed four times higher DFS than children with low numbers. The magnitude of salivary cariogenic bacteria as well as caries prevalence was found to resemble the situation in Sweden 10 yr ago. S. mutans (serotype c/e/f) was carried by all mutans streptococci positive children. S. sobrinus (serotype d/g) was found in 60 children (30.2%). Children with both S. mutans and S. sobrinus had significantly higher salivary counts of mutans streptococci and lactobacilli as well as caries prevalence than children with only S. mutans.     

Cariogenic microorganisms and oral conditions in asthmatic children

This study evaluated the caries risk of asthmatic patients on the basis of mutans streptococci (MS) and lactobacilli levels in saliva samples as well as the index of oral hygiene and dental caries (DMFT index). The study population was composed of 80 asthmatic children, aged 3-15 years, who use specific medication, and 80 matched, healthy control children. The parents were interviewed about oral health-related factors. The World Health Organization criteria were used for dental examinations. The K?hler and Bratthal methodology was used to detect salivary MS levels and dilutions of saliva were done for lactobacilli counting. No differences between asthma and control groups were observed for caries prevalence in children aged 3-6 and 7-10 years, except in severe cases in the younger group. However, higher caries prevalence for permanent dentition was observed in 11- to 15-year-old asthmatic children. An increased dental biofilm was observed in the asthma group, as well as salivary levels of MS. No differences were observed in levels of lactobacilli. No statistical correlations were found between medication, frequency of treatment, method of consumption and caries experience, dental biofilm and salivary levels of MS or lactobacilli. However, there was a correlation between MS levels and treatment duration. The logistic regression revealed that MS level is an important risk factor for increased caries experience. Asthma should be evaluated as a risk factor for caries experience because it can increase the levels of MS and the dental biofilm.     

Lactobacillus-mediated interference of mutans streptococci in caries-free vs. caries-active subjects

In order to assess whether naturally occurring oral lactobacilli have probiotic properties, lactobacilli were isolated from saliva and plaque from children and adolescents, with or without caries lesions. The interference capacities of these lactobacilli were investigated against a panel of 13 clinical isolates and reference strains of Streptococcus mutans and Streptococcus sobrinus, as well as against the subject's autologous mutans streptococci, using the agar-overlay technique. Lactobacillus-mediated inhibition differed significantly between the three subject groups (no caries, arrested caries, or active caries), demonstrating increased inhibition in subjects without present or previous caries experience compared to subjects with arrested caries or subjects presenting with frank lesions. Lactobacilli from subjects lacking S. mutans inhibited the growth of the test panel of mutans streptococci significantly better than lactobacilli from subjects who were colonized. Furthermore, subjects without caries experience harbored lactobacilli that more effectively repressed the growth of their autologous mutans streptococci. Twenty-three Lactobacillus spp. completely inhibited the growth of all mutans streptococci tested. Species with maximum interference capacity against mutans streptococci included Lactobacillus paracasei, Lactobacillus plantarum, and Lactobacillus rhamnosus. Naturally occurring oral lactobacilli significantly inhibited the growth of both test strains of mutans streptococci and the subject's autologous mutans streptococci in vitro, and this effect was more pronounced in caries-free subjects.     

Prediction of caries activity in children with today''s low caries incidence

One hundred 14-yr-old children were observed over 1 yr to find out if caries incidence and caries progression could be predicted in a low prevalence child population by means of well-known caries related factors. The mean caries incidence was low (0.45, SD 0.70) but, on the other hand, 32% of the children developed at least one new lesion during the test period. In only eight out of 35 children progressing lesions were demonstrated. Independent variables at baseline examination were caries prevalence, sucrose intake, fluoride exposure, oral hygiene, saliva secretion rate, and salivary concentrations of mutans streptococci and lactobacilli. A weak but statistically significant correlation was demonstrated between caries incidence and caries prevalence. No other significant correlations were shown. It was concluded that caries activity could not be predicted in this population. Low disease prevalence was a major reason for the weak correlations.     

Antimicrobial effect of fluoride mouthrinse on mutans streptococci and lactobacilli in saliva

PURPOSE: This study was designed to determine whether the long-term use of fluoride mouthrinse affects the salivary levels of mutans streptococci and lactobacilli. METHODS: The subjects consisted of 414 school children aged 7, 10, and 12 yrs. Among these subjects, 243 children had received fluoride mouthrinse since 5 years of age at nursery schools, and comprised the "mouthrinse group." The remaining 171 children, the "no mouthrinse group," had not received fluoride mouthrinse. All of the children received routine dental health education. The levels of mutans streptococci and lactobacilli for the subjects in both groups were measured using Dentocult SM Strip mutans and Dentocult LB Dip Slide, respectively. Dental examinations were conducted to obtain data on caries prevalence (dfs and DMFS). Logistic regression analysis was used to control confounding factors: age, dfs, DMFS, frequency of toothbrushing, sum of permanent tooth surfaces sealed, frequency of sweet snacks, frequency of sweet drinks, and the use of fluoridated toothpaste. RESULTS: There was a significant difference in mean DMFS between the mouthrinse group and no mouthrinse group at all ages. Children with fluoride mouthrinse had lower levels of mutans streptococci, and there was a significant association between the experience of fluoride mouthrinse and the score of Dentocult SM strip Odds ratio: 0.64, P < 0.05. However, there was no significant relation between the experience of fluoride mouthrinse and the score of Dentocult LB Dip Slide. The results of this study demonstrated that the long-term use of fluoride mouthrinse affected the detectable levels of mutans streptococci, but did not affect the levels of lactobacilli. CONCLUSIONS: These results suggest that fluoride mouthrinse might contribute to reducing the number of mutans streptococci.     

Mutans streptococci, lactobacilli and caries prevalence in 15 to 16-year olds in G?teborg. Part II.

During the fall of 1987 one hundred and fifty-five 15 to 16-year-olds were examined with regard to caries prevalence, saliva secretion rate and salivary numbers of mutans streptococci and lactobacilli. In 15% of the subjects no mutans streptococci were detected, while 17.7% carried > 10(6) colony forming units (cfu) per ml saliva. The median value was 1.8 x 10(5) cfu per ml saliva. No lactobacilli were detected in 19% of the subjects and 14.3% had > 10(5) cfu per ml saliva. The mean caries prevalence was 21.0, of these 14.1 were incipient lesions. Increased numbers of mutans streptococci and lactobacilli were associated with increasing caries prevalence. Subjects with high numbers of both microorganisms showed about 4 times higher mean caries prevalence than those with low numbers. Streptococcus sobrinus carriers (15%) had both higher mean caries prevalence and a higher proportion of subjects with > 10(6) cfu mutans streptococci per ml saliva than was found in the whole group.     

Dental caries and prolonged breast-feeding in 18-month-old Swedish children

Summary. Three thousand children aged 18 months were screened for dental caries and ongoing breast-feeding at 46 child welfare centres in different parts of Sweden. Of these, 200 children were selected for a more comprehensive examination, involving investigation of dietary, toothbrushing and sucking habits, use of fluoride, and determination of salivary levels of mutans streptococci and lactobacilli. The children were divided into four groups: group 1: children with caries not being breast-fed; group 2: children with caries being breast-fed; group 3: caries-free children being breast-fed; group 4: caries-free gender- and age-matched reference children not being breast-fed. The results showed that 63 of the children (2.1%) had caries and 61 (2.0%) were still being breast-fed. Twelve (19.7%) of the 61 children still being breast-fed had caries compared with 51 (1.7%) of the 2939 children not being breast-fed; the difference was statistically significant. Children with caries and still being breast-fed had a mean defs of 5.3, and those with caries not being breast-fed 4.9; the difference was not statistically significant. Children with caries, irrespective of whether they were being breast-fed or not, had significantly higher numbers of cariogenic food intakes per day than caries-free children. Mutans streptococci were detected in 67% of the children and lactobacilli in 13%. Children with detectable mutans streptococci and lactobacilli had significantly more caries than those without. The results indicate that Swedish children with prolonged breast-feeding have a tendency to establish unsuitable dietary habits which constitutes a risk situation for developing caries at an early age.     

Relationship of microbial and salivary parameters with dental caries in Brazilian pre-school children

Caries examination and collection of paraffin wax-stimulated saliva samples were performed in 37 children, 3-6 years old, in a child-care facility at the Vidigal slum, Rio de Janeiro, Brazil. The levels of mutans streptococci and lactobacilli in saliva were estimated by the Cariescreen and by the Dentocult tests and the saliva secretion rate was determined. Statistical analysis was performed on surface-based and patient-based caries prevalence rates (SBCPR and PBCPR), and related to bacterial and salivary parameters. The results show that 31 of the 37 children were caries active. The SBCPR for the primary dentition was 6.7% +/- 1.0%. Occlusal surfaces were the most affected by decay. Regression analysis revealed that mutans streptococci salivary levels were significantly associated with the SBCPR (P = 0.0001). Similarly, lactobacilli salivary levels were significantly associated with the SBCPR (P = 0.0001). No significant association could be found between the saliva secretion rate and the SBCPR. When regression analysis was used to model dependence of the SBCPR on both organisms, the mutans streptococci and lactobacilli salivary levels were significantly associated with the SBCPRs (P = 0.0021 and 0.0118, respectively), and salivary levels of these organisms accounted for 57% of the SBCPR variability. These findings indicate that the levels of mutans streptococci and lactobacilli in saliva are significantly related to the SBCPRs on the primary dentition of these children.     

On the pH-lowering potential of lactobacilli and mutans streptococci from dental plaque related to the prevalence of caries

Abstract The common method used today to identify persons at risk of dental caries is to estimate the numbers of cariogenic bacteria such as lactobacilli and mutans streptococci in saliva or plaque samples taken from the patient. However, the value of these bacterial counts for explaining and predicting individuals at risk of caries has not been powerful enough. Evaluating one virulence factor such as the acidogenicity of these bacteria might increase their explanatory values for caries. Sixty children aged 14–15 yrs participated in this study. Smooth surface caries and restorations were registered and total plaque samples collected. Counts of lactobacilli and mutans streptococci were estimated, and the pH-lowering potential of both bacteria was measured in an adapted glucose broth. The results showed a weak association between dental caries and lactobacilli, but in the subgroup with this bacterium the explanatory value increased to 14% and in the subgroup with a strong pH-lowering potential it was as high as 27%. For mutans streptococci the associations were weak in all groups.