title: Rural and urban disparities in caries prevalence in children with unmet dental needs: the New England Children's Amalgam Trial.
abstract: OBJECTIVE
  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.
authors.affiliation: New England Research Institutes, 9 Galen Street, Watertown, MA 02472, USA. nmaserejian@neriscience.com
authors.forename: Nancy Nairi
authors.initials: NN
authors.lastname: Maserejian
authors.forename: Mary A
authors.initials: MA
authors.lastname: Tavares
authors.forename: Catherine
authors.initials: C
authors.lastname: Hayes
authors.forename: Jennifer A
authors.initials: JA
authors.lastname: Soncini
authors.forename: Felicia L
authors.initials: FL
authors.lastname: Trachtenberg
mesh_terms: D001900:Boston / Q000453:epidemiology; D002648:Child; D003188:Composite Resins; D003723:Dental Amalgam; D003731:Dental Caries / Q000453:epidemiology*; D003793:Dental Restoration, Permanent / Q000379:methods; D019229:Dentition, Permanent; D005260:Female; D005457:Fluoridation; D006301:Health Services Needs and Demand / Q000706:statistics & numerical data; D054624:Health Status Disparities; D006801:Humans; D008281:Maine / Q000453:epidemiology; D008297:Male; D015233:Models, Statistical; D015995:Prevalence; D016032:Randomized Controlled Trials as Topic; D012423:Rural Health / Q000706:statistics & numerical data*; D014094:Tooth, Deciduous; D014504:Urban Health / Q000706:statistics & numerical data*
chemical_list: D003188:Composite Resins; D003723:Dental Amalgam