Oral microbiota of children in a school-based dental clinic.

OBJECTIVES: Dental caries disproportionately affects disadvantaged subjects. This study hypothesized that there were greater caries extent and higher levels of caries-associated and anaerobic subgingival bacterial species in oral samples of Hispanic and immigrant children compared with non-Hispanic and US born children. METHODS: Children from a school-based dental clinic serving a community with a large Hispanic component were examined, and the extent of caries was recorded. Microbial samples were taken from teeth and the tongues of children. Samples were analyzed using DNA probes to 18 oral bacterial species. RESULTS: Seventy five children were examined. Extent of caries increased with child age in immigrant, but not in US born or Hispanic children. There were no differences in the microbiota based on ethnicity or whether the child was born in US or not. There was a higher species detection frequency from teeth than tongue samples. Levels of Streptococcus mutans and other Streptococcus spp increased with caries extent. Prevotella intermedia, Tannerella forsythia and Selenomonas spp were detected at low levels in these children. CONCLUSIONS: We conclude that, while there was a high rate of dental caries in disadvantaged school children, there were no differences in the caries-associated microbiota, including S. mutans, based on ethnicity or immigration status. Furthermore, while anaerobic subgingival, periodontal pathogens were also detected in children, there was no difference in species detection based on ethnicity or immigration status. Increased levels of streptococci, including S. mutans, however, were detected with high caries levels. This suggested that while it is beneficial to target preventive and treatment programs to disadvantaged populations, there is likely no additional benefit to focus on subgroups within a population already at high risk for dental disease.

Prospective study of 5-year caries increment among children receiving comprehensive dental care in the New England children's amalgam trial.

OBJECTIVE: To measure the 5-year caries increment among high-risk children during their participation in the New England Children's Amalgam Trial (NECAT), and to evaluate sociodemographic factors that may account for any observed disparities. METHODS: NECAT recruited 534 children aged 6-10 with at least two decayed posterior occlusal surfaces from urban Boston and rural Maine. After restoration of baseline caries and application of sealants to sound surfaces, NECAT continued to provide free comprehensive semiannual dental care to participants. The net caries increment of children who completed the 5-year follow-up (n = 429) was calculated and predictors of caries increment were investigated using multivariate negative binomial models. RESULTS: The majority of children (89%) experienced new caries by the end of the 5-year follow-up. Almost half (45%) had at least one newly decayed surface by the first annual visit. At year 5, the mean number of new decayed teeth was 4.5 +/- 3.6 (range 0-25) and surfaces was 6.9 +/- 6.5 (range 0-48). Time trends showed a noticeably higher increment rate among older children and young teenagers. Multivariate models showed that age (P < 0.001), number of baseline carious surfaces (P < 0.001), and toothbrushing frequency (<1/day versus >or=2/day, P = 0.04) were associated with caries increment. Only 48 children (11%) did not develop new caries. CONCLUSIONS: Despite the receipt of comprehensive semiannual dental care, the vast majority of these high-risk children continued to develop new caries within 5 years. While disparities were observed by age, extent of prior decay, and toothbrushing frequency, no other sociodemographic factors were associated with caries increment, suggesting that the dental care provided during the trial reduced sociodemographic disparities in prior caries experience that were observed at baseline.

Rural and urban disparities in caries prevalence in children with unmet dental needs: the New England Children's Amalgam Trial.

OBJECTIVES: To compare the prevalence of caries between rural and urban children with unmet dental health needs who participated in the New England Children's Amalgam Trial. METHODS: Baseline tooth and surface caries were clinically assessed in children from rural Maine (n = 243) and urban Boston (n = 291), who were aged 6 to 10 years, with two or more posterior carious teeth and no previous amalgam restorations. Statistical analyses used negative binomial models for primary dentition caries and zero-inflated models for permanent dentition caries. RESULTS: Urban children had a higher mean number of carious primary surfaces (8.5 versus 7.4) and teeth (4.5 versus 3.9) than rural children. The difference remained statistically significant after adjusting for sociodemographic factors and toothbrushing frequency. In permanent dentition, urban children were approximately three times as likely to have any carious surfaces or teeth. However, rural/urban dwelling was not statistically significant in the linear analysis of caries prevalence among children with any permanent dentition caries. Covariates that were statistically significant in all models were age and number of teeth. Toothbrushing frequency was also important for permanent teeth. CONCLUSIONS: Within this population of New England children with unmet oral health needs, significant differences were apparent between rural and urban children in the extent of untreated dental decay. Results indicate that families who agree to participate in programs offering reduced cost or free dental care may present with varying amounts of dental need based on geographic location.