Severe Early Childhood Caries Children Research Articles

Short Communication: Polymicrobial community in teeth associated with severe early-childhood caries

This was to characterise the microbial diversity in the complex dental plaque of children with severe early-childhood caries (S-ECC), using the denaturing gel gradient electrophoresis (DGGE) technique. The DGGE technique was used as a diagnostic tool to analyse samples from the oral cavity of a patient with S-ECC. Dental plaque samples from a 3-year-old child with S-ECC were taken from the primary central maxillary incisor (biofilm on vestibular surface), primary maxillary molar (biofilm on vestibular surface), primary central maxillary incisor (dentine), primary maxillary molar (dentine) and saliva and then analysed by PCR-DGGE. Three bands occurred in all samples, moreover, 86% of similarity was observed in the pattern of bands between incisor and molar teeth biofilm samples, including four similar bands. DGGE is a valuable tool for differentiating the microbial composition of the oral plaque in S-ECC children.

Microcosm Biofilms Originating from Children with Different Caries Experience Have Similar Cariogenicity under Successive Sucrose Challenges

Objectives: The source of saliva inocula and the individual characteristics of saliva donors could affect the cariogenic activity of in vitro biofilms, but this could also be modulated by environmental determinants, such as the frequency of sugar consumption. Therefore, the aim of this study was to compare the cariogenicity of microcosm biofilm growths from the saliva of caries-free (CF) children, children with early childhood caries (ECC) and with severe ECC (S-ECC), under regular sucrose exposure. Methods: Microcosm plaque biofilms were initiated from the saliva of CF, ECC and S-ECC children. Biofilms were grown in 24-well microplates on bovine enamel discs for up to 10 days in artificial saliva, which was replaced daily. Growth conditions comprised cariogenic challenge (artificial saliva supplemented with 1% sucrose 6 h/day) or no cariogenic challenge. Daily pH was obtained from the artificial saliva, and after the experimental period, the biofilm formed on the enamel discs was collected for microbiological analyses. Mineral loss in enamel discs was estimated by percentage of surface hardness change. Results: Overall, no statistically significant differences were found among saliva sources (p > 0.05). Streptococcus mutans and lactobacilli counts increased in the biofilms grown under cariogenic challenge (p < 0.05), while a substantial decrease in the artificial saliva pH was detected under the same condition (p < 0.001). Higher demineralization (p < 0.001) was observed under sucrose exposure regardless of caries experience of children. Conclusions: While the sucrose exposure determined the cariogenicity of the biofilms, the caries experience of children who provided the inocula did not affect mineral loss associated with these biofilms.

Genotypic diversity of Streptococcus mutans and Streptococcus sobrinus in 3-4-year-old children with severe caries or without caries

BACKGROUND. The genotypic diversity of both Streptococcus mutans and Streptococcus sobrinus in children with different caries experience remains unclear. AIM. To investigate the genotypic diversity of S. mutans and S. sobrinus in children with severe early childhood caries (SECC) and in caries-free (CF) children. METHODS. Stimulated saliva of 87 SECC and 91 CF children aged 3-4 years was collected and submitted to cultivation, and MS colonies were enumerated. The genomic fingerprint analysis of S. mutans and S. sobrinus was carried out using AP-PCR. RESULTS. One to five genotypes of S. mutans were colonized in an oral cavity of SECC and CF children; 85.5% SECC children and 57.9% CF children harboured more than one genotype of S. mutans. One to three genotypes of S. sobrinus were detected from each SECC child; 31.25% SECC children harboured more than one genotype of S. sobrinus. And one genotype was colonized in each CF child. S. mutans isolates from different individuals displayed distinctive DNA fingerprints. CONCLUSIONS. DNA fingerprints of S. mutans and S. sobrinus isolates from 3- to 4-year-old children displayed genetic polymorphism, and S. mutans has greater genetic diversity than S. sobrinus. SECC children harboured more genotypes of S. mutans and S. sobrinus than CF children.

Diet and Caries-associated Bacteria in Severe Early Childhood Caries

Frequent consumption of cariogenic foods and bacterial infection are risk factors for early childhood caries (ECC). This study hypothesized that a short diet survey focused on frequency of foods, categorized by putative cariogenicity, would differentiate severe ECC (S-ECC) from caries-free children. Children’s diets were obtained by survey and plaque bacteria detected by PCR from 72 S-ECC and 38 caries-free children. S-ECC children had higher scores for between-meal juice (p < 0.01), solid-retentive foods (p < 0.001), eating frequency (p < 0.005), and estimated food cariogenicity (p < 0.0001) than caries-free children. S-ECC children with lesion recurrence ate fewer putative caries-protective foods than children without new lesions. Streptococcus mutans (p < 0.005), Streptococcus sobrinus (p < 0.005), and Bifidobacteria (p < 0.0001) were associated with S-ECC, and S. mutans with S. sobrinus was associated with lesion recurrence (p < 0.05). S. mutans-positive children had higher food cariogenicity scores. Food frequency, putative cariogenicity, and S. mutans were associated with S-ECC individually and in combination.

A comparison of a generic and oral health–specific measure in assessing the impact of early childhood caries on quality of life

The aim of this study was to compare the performance of a generic health-related quality-of-life measure, the Pediatric Quality of Life Inventory Version 4.0 (PedsQL 4.0) and an oral health-specific quality-of-life measure, the Early Childhood Oral Health Impact Scale (ECOHIS) in assessing the impact of severe early childhood caries (S-ECC) on the children's quality of life. A trained and calibrated examiner conducted a clinical oral assessment of 111 children (mean age: 49 +/- 12 months): 64 of whom were categorized as having S-ECC and 47 as being caries-free. Primary caregivers completed a Chinese version of the PedsQL 4.0 and the ECOHIS. Clinical examinations were conducted blind of the parental assessments. The ECOHIS scores were significantly higher for the S-ECC group than for the caries-free group (P < or = 0.001). No significant difference was found between the PedsQL 4.0 scores in relation to caries status, except for the subscale of physical functioning (P = 0.04). Correlation of caries status with the ECOHIS scores was strong (r = 0.66; P < 0.01). No significant correlation was found between PedsQL 4.0 scores and caries status (r = 0.02; P > 0.05). The oral health-specific measure, ECOHIS, shows better discriminant property between children with S-ECC and caries-free children than the generic measure, PedsQL 4.0. The ECOHIS appears more sensitive than PedsQL 4.0 in assessing the impact of dental caries on the life quality of preschool children.

Severe early childhood caries and behavioral risk factors among 3-year-old children in Lithuania

The objective of the present study was to investigate the prevalence and severity of early childhood caries (ECC) and severe early childhood caries (S-ECC) in 3-year-old Lithuanian children. The impact of selected behavioral risk factors on the development of S-ECC was investigated. A total of 950 children were examined in kindergartens. Diagnosis of dental caries followed the WHO criteria. Questionnaires were delivered to mothers of the children with S-ECC and caries-free children. The questions were related to the children's dietary habits, temperament, oral hygiene, and the use of fluoride toothpaste. The prevalence of ECC was 50.6% with a mean dmft of 2.1 (SD, 0.1) and a mean dmfs of 3.4 (SD, 0.2). The prevalence of S-ECC was 6.5% with a mean dmft of 7.8 (SD, 0.1) and dmfs of 18.1 (SD, 0.6). A significantly higher percentage of children developed S-ECC when they were breast-fed for a period longer than one year, were sleeping with a bottle containing carbohydrates during the night, or were allowed to sip from a bottle either going to sleep or during the day. A significantly higher percentage of mothers having caries-free children knew about risk factors of S-ECC and started tooth brushing after the eruption of the first tooth. There was no significant difference between the groups regarding the use of fluoride toothpaste. Improper infant bottle-feeding habits and no tooth brushing were found to be significant for the development of S-ECC among 3-year-old Lithuanian children.

Genotypic diversity of Streptococcus sobrinus in 3 to 4-year-old children suffering with severe early childhood caries

To evaluate the genotypic diversity of Streptococcus sobrinus (Ss) between children suffering with severe early childhood caries (S-ECC) and caries-free children by arbitrarily primed-polymerase chain reaction (AP-PCR). A total of 178 children aged from 42 to 54 months were recruited from 14 urban kindergartens. The S-ECC group contained 87 children with more than 5 decayed teeth, and the control group was composed of 91 caries-free children. Stimulated whole saliva was collected by chewing paraffin. All mutans streptococcus isolates were subcultured, biochemically characterised and identified by PCR as Streptococcus mutans (Sm) and Ss. Then the Ss isolates were genotyped by AP-PCR. The frequency of Ss detection was 18% in S-ECC children, which was significantly higher than 3% in caries-free children (P < 0.01). Twenty-two distinct genotypes of Ss were identified from 53 clinical isolates. In S-ECC group, one to three genotypes of Ss were detected in each saliva sample. Only one genotype of Ss was detected in all the caries-free children. One genotype of Ss were shared by three S-ECC children. The genotypes of isolates in S-ECC group were relate to decayed-missing-filled teeth (r = 0.50, P < 0. 05). The rate of Ss detection was significantly higher in S-ECC children than in caries-free children. Isolates of Ss displayed genetic polymorphism. The multi-genotypes of Ss was related to differences in caries susceptibility. Strains of Ss with same genotype were present in unrelated subjects.

Streptococcus mutans and Streptococcus sanguinis Colonization Correlated with Caries Experience in Children

The aim of this study was to examine the colonization of Streptococcus mutans and Streptococcus sanguinis in the oral cavity and the association with severe early childhood caries (S-ECC). Saliva and plaque samples were collected from 14 S-ECC children and 8 caries-free (CF) children. All S-ECC children were S. mutans positive; 100% of CF children and 93% of S-ECC children were S. sanguinis positive. The children’s caries severity was positively correlated with levels of S. mutans (p < 0.001), total oral streptococci (p < 0.01), total cultivable oral bacteria (p < 0.05), and children’s age (p < 0.05). Logistic regression analysis showed that the interaction of S. sanguinis with S. mutans was a significant factor associated with the caries status in children, suggesting that the relative levels of these two microorganisms in the oral cavity play an important role in caries development.

Genetic Profiling of the Oral Microbiota Associated with Severe Early-Childhood Caries

The determination of the composition of the microbial community in the oral cavity is usually based on cultivation methods; however, nearly half of the bacteria in the saliva and the dental plaque are not cultivable. In this study, we evaluated the difference in oral microbial diversity between children with severe early-childhood caries (S-ECC) and caries-free (CF) controls by means of a cultivation-independent approach called denaturing gradient gel electrophoresis (DGGE). Pooled dental plaque samples were collected from 20 children aged 2 to 8 years. Total microbial genomic DNA was isolated from those subjects, and a portion of the 16S rRNA gene locus was PCR amplified by using universal primers. We observed that the mean species richness of the bacterial population was greater in the CF children (n = 12) (42 +/- 3.7) than in the S-ECC children (n = 8) (35 +/- 4.3); the difference was statistically significant (P = 0.005). The overall diversity of plaque samples as measured by the Shannon index was 3.5 for the S-ECC group and 3.7 for the CF group (P = 0.004). Differences in DGGE profiles were distinguished on the basis of a cluster analysis. Sequence analysis of excised DGGE bands consisted of 2.7 phylotypes, on average. After adjusting for the number of observed bands, we estimated that the S-ECC group exhibited 94.5 total phylotypes and that the CF group exhibited 113.4. These results suggest that the microbial diversity and complexity of the microbial biota in dental plaque are significantly less in S-ECC children than in CF children.