title: Genetic variation in MMP20 contributes to higher caries experience.
abstract: Matrix metalloproteinases play an important role during the initial process of enamel development and therefore may play a role in caries.
  
  
  OBJECTIVE
  To evaluate the association between MMP20 and caries experience in Brazilian children.
  
  
  METHODS
  Eligible unrelated children with or without caries were evaluated using a cohort design. Demographic data and oral health habits were obtained though a questionnaire. Caries data was collected by clinical examination. Genotyping of the selected polymorphism was carried out by real-time PCR from genomic DNA. Allele and genotype frequencies were compared between groups with distinct caries experience and oral health habits.
  
  
  RESULTS
  Of 388 subjects, 161 were caries free children. There were no differences between caries levels and genotype distribution in the total cohort. When ethnic background was considered, differences in genotype distribution were observed in caries free children vs. children with caries in Caucasians (p=0.03). Differences could also be seen when poor oral hygiene was used to stratify the analysis (p=0.02). Regression analysis, adjusted for genotype and ethnicity, confirmed that ingestion of sweets between meals increases the risk of presenting carious lesions (p=0.00001; OR=2.33; 95%CI 1.53-3.54).
  
  
  CONCLUSIONS
  Variation in MMP20 may be associated with caries experience mainly in Caucasian subjects with poor oral health habits.
authors.affiliation: Department of Paediatric Dentistry and Orthodontics, School of Dentistry, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors.forename: Patricia Nivoloni
authors.initials: PN
authors.lastname: Tannure
authors.forename: Erika Calvano
authors.initials: EC
authors.lastname: Küchler
authors.forename: Andrea
authors.initials: A
authors.lastname: Lips
authors.forename: Marcelo de Castro
authors.initials: Mde C
authors.lastname: Costa
authors.forename: Ronir Raggio
authors.initials: RR
authors.lastname: Luiz
authors.forename: Jose Mauro
authors.initials: JM
authors.lastname: Granjeiro
authors.forename: Alexandre Rezende
authors.initials: AR
authors.lastname: Vieira
mesh_terms: D000293:Adolescent; D044466:Asian People / Q000235:genetics; D044383:Black People / Q000235:genetics; D002182:Candy; D002327:Cariostatic Agents / Q000627:therapeutic use; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D003596:Cytosine; D004245:DMF Index; D003731:Dental Caries / Q000201:enzymology / Q000235:genetics*; D003742:Dental Devices, Home Care; D005006:Ethnicity / Q000235:genetics; D005247:Feeding Behavior; D005260:Female; D005459:Fluorides / Q000627:therapeutic use; D005787:Gene Frequency / Q000235:genetics; D014644:Genetic Variation / Q000235:genetics*; D005838:Genotype; D006801:Humans; D008297:Male; D053519:Matrix Metalloproteinase 20 / Q000235:genetics*; D009910:Oral Hygiene; D011110:Polymorphism, Genetic / Q000235:genetics; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D013941:Thymine; D014099:Toothbrushing; D014100:Toothpastes / Q000627:therapeutic use; D044465:White People / Q000235:genetics
chemical_list: D002327:Cariostatic Agents; D014100:Toothpastes; D003596:Cytosine; C507111:MMP20 protein, human; D053519:Matrix Metalloproteinase 20; D005459:Fluorides; D013941:Thymine