title: Amoxicillin use during early childhood and fluorosis of later developing tooth zones.
abstract: OBJECTIVE
  Amoxicillin use has been reported to be associated with developmental defects on enamel surfaces. This analysis assessed the association between amoxicillin use and fluorosis on late-erupting permanent teeth.
  
  
  METHODS
  As part of the Iowa Fluoride Study, subjects were followed from birth to 32 months with questionnaires every 3-4 months to gather information on fluoride intake and amoxicillin use (n = 357 subjects for this analysis). Permanent tooth fluorosis on late-erupting zones was assessed by three trained dentists using the fluorosis risk index (FRI) at approximately age 13. A case was defined as fluorosis if a subject had at least two FRI classification II zone scores of 2 or 3. Chi-square tests and logistic regression were used, and relative risks (RRs) and odds ratios (ORs) were calculated.
  
  
  RESULTS
  There were 113 cases and 244 controls. In bivariate analyses, amoxicillin use from 20 to 24 months significantly increased the risk of fluorosis on FRI classification II zones [44.2 percent versus 30.4 percent, [RR = 1.45, 95 percent confidence interval (CI) 1.05-2.04], but other individual time periods did not. Multivariable logistic regression confirmed the increased risk of fluorosis for amoxicillin use from 20 to 24 months (OR = 2.92, 95 percent CI = 1.34-6.40), after controlling for otitis media, breast-feeding, and fluoride intake.
  
  
  CONCLUSIONS
  Amoxicillin use during early childhood could be a risk factor in the etiology of fluorosis on late-erupting permanent tooth zones, but further research is needed.
authors.affiliation: Department of Pediatric Dentistry and Community Oral Health, College of Dentistry, University of Tennessee Health Science Center, Memphis, TN 38163, USA.
authors.forename: Liang
authors.initials: L
authors.lastname: Hong
authors.forename: Steven M
authors.initials: SM
authors.lastname: Levy
authors.forename: John J
authors.initials: JJ
authors.lastname: Warren
authors.forename: Barbara
authors.initials: B
authors.lastname: Broffitt
mesh_terms: D000658:Amoxicillin / Q000009:adverse effects*; D016022:Case-Control Studies; D002675:Child, Preschool; D009050:Fluorosis, Dental / Q000209:etiology*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007484:Iowa; D011795:Surveys and Questionnaires; D014070:Tooth / Q000187:drug effects* / Q000254:growth & development
chemical_list: D000658:Amoxicillin