title: Re-Examining the Association between Vitamin D and Childhood Caries.
abstract: BACKGROUND
  Previous studies have reported an inverse association between vitamin D and childhood dental caries, but whether this is causal is unclear.
  
  
  OBJECTIVE
  To determine the causal effect of circulating 25-hydroxyvitamin D concentration on dental caries experience, early caries onset and the requirement for a dental general anesthetic.
  
  
  METHODS
  A Mendelian randomization study was undertaken, using genetic variants known to be associated with circulating 25-hydroxyvitamin D concentrations in 5,545 European origin children from the South West of England. Data on caries and related characteristics were obtained from parental and child completed questionnaires between 38 and 91 months and clinical assessments in a random 10% sample at 31, 44 and 61 months.
  
  
  RESULTS
  In multivariable confounder adjusted analyses no strong evidence for an association of 25-hydroxyvitamin D with caries experience or severity was found but there was evidence for an association with early caries onset, or having a general anesthetic for dental problems. In Mendelian randomization analysis the odds ratio for caries experience per 10 nmol/L increase in 25-hydroxyvitamin D was 0.93 (95% confidence interval: 0.83, 1.05; P = 0.26) and the odds ratio for dental general anaesthetic per 10 nmol/L increase in 25-hydroxyvitamin D was 0.96 (95% confidence interval: 0.75, 1.22; P = 0.72).
  
  
  CONCLUSIONS
  This Mendelian randomization study provides little evidence to support an inverse causal effect of 25-hydroxyvitamin D on dental caries. However, the estimates are imprecise and a larger study is required to refine these analyses.
authors.affiliation: MRC Integrative Epidemiology Unit, School of Community and Social Medicine, University of Bristol, Bristol, United Kingdom.|School of Oral and Dental Science, Bristol University, Bristol, United Kingdom.
authors.forename: Tom
authors.initials: T
authors.lastname: Dudding
authors.affiliation: School of Oral and Dental Science, Bristol University, Bristol, United Kingdom.
authors.forename: Steve J
authors.initials: SJ
authors.lastname: Thomas
authors.affiliation: School of Oral and Dental Science, Bristol University, Bristol, United Kingdom.
authors.forename: Karen
authors.initials: K
authors.lastname: Duncan
authors.affiliation: MRC Integrative Epidemiology Unit, School of Community and Social Medicine, University of Bristol, Bristol, United Kingdom.
authors.forename: Debbie A
authors.initials: DA
authors.lastname: Lawlor
authors.affiliation: MRC Integrative Epidemiology Unit, School of Community and Social Medicine, University of Bristol, Bristol, United Kingdom.
authors.forename: Nicholas J
authors.initials: NJ
authors.lastname: Timpson
mesh_terms: D002648:Child; D002675:Child, Preschool; D003731:Dental Caries / Q000097:blood* / Q000453:epidemiology* / Q000235:genetics; D004739:England / Q000453:epidemiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006887:Hydroxycholecalciferols / Q000097:blood*; D008297:Male; D011795:Surveys and Questionnaires
chemical_list: D006887:Hydroxycholecalciferols