title: Examining the socioeconomic effects on third molar maturation in a Portuguese sample of children, adolescents and young adults.
abstract: BACKGROUND
  The impact of socioeconomic status (SES) on tooth mineralization has seldom been evaluated. This is important because SES can be used as a proxy for quantifying factors in the environmental that can impact mineralization but that can be difficult to measure directly, such as nutrition.
  
  
  OBJECTIVE
  The objective of this study was to examine the effects of SES on third molar mineralization, using a sample of children, adolescents and young adults from Porto, Portugal.
  
  
  METHODS
  Panoramic x-rays from 1747 patients (842 males and 904 females) were used in this study. Eight hundred and fifteen individuals were patients attending a private practice and were classified as high SES (384 males and 458 females), whereas the remaining 932 subjects (458 males and 474 females) were patients attending the dental clinic at the Faculty of Dental Medicine, University of Porto and were classified as low SES. Inclusion of individuals on the each SES group was also based on parental and own occupation. The mandibular third molar was assessed for its maturation using Demirjian's stages. The median age of attainment of root stages was calculated for stages D to H, using logistic regression and compared between the high and low SES samples.
  
  
  RESULTS
  Boys from the higher SES group show an earlier median age of attainment for stages D, E, and F. Girls from the higher SES group also show an earlier median age of attainment, but for stages D and E. Stages G and H did not show SES differences in both sexes.
  
  
  CONCLUSIONS
  Patients from the higher SES group showed a consistent advancement in maturation of the third molar, although SES differences diminish and eventually disappear in the last stages of root maturation. An accelerated effect related to overweight and obesity is suggested as the primary explanation.
authors.affiliation: Department of Legal Medicine and Forensic Sciences, Faculty of Medicine, University of Porto, 4200-319, Porto, Portugal.
authors.forename: J L
authors.initials: JL
authors.lastname: Carneiro
authors.affiliation: Faculty of Dental Medicine, University of Porto, Rua Dr. Manuel Pereira da Silva, 4200-3939, Porto, Portugal. icaldas@fmd.up.pt.|Forensic Sciences Centre - CENCIFOR, Largo da Sé Nova, Coimbra, Portugal. icaldas@fmd.up.pt.|Centre for Functional Ecology, Laboratory of Forensic Anthropology, Department of Life Sciences, University of Coimbra, Calçada Martim Freitas, Coimbra, 3000-456, Portugal. icaldas@fmd.up.pt.|IINFACTS - Institute of Research and Advanced Training in Health Sciences and Technologies, Department of Sciences, University Institute of Health Sciences (IUCS), CESPU, CRL, Gandra, Portugal. icaldas@fmd.up.pt.
authors.forename: I M
authors.initials: IM
authors.lastname: Caldas
authors.affiliation: Faculty of Dental Medicine, University of Porto, Rua Dr. Manuel Pereira da Silva, 4200-3939, Porto, Portugal.|Forensic Sciences Centre - CENCIFOR, Largo da Sé Nova, Coimbra, Portugal.|IINFACTS - Institute of Research and Advanced Training in Health Sciences and Technologies, Department of Sciences, University Institute of Health Sciences (IUCS), CESPU, CRL, Gandra, Portugal.
authors.forename: A
authors.initials: A
authors.lastname: Afonso
authors.affiliation: Department of Archaeology, Simon Fraser University, 8888 University Drive, Burnaby, BC, V5A 1S6, Canada.
authors.forename: H F V
authors.initials: HF
authors.lastname: Cardoso
mesh_terms: D000293:Adolescent; D000328:Adult; D000366:Age Determination by Teeth; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008297:Male; D008334:Mandible; D008964:Molar, Third / Q000000981:diagnostic imaging / Q000254:growth & development*; D011174:Portugal; D012923:Social Class; D014074:Tooth Calcification; D055815:Young Adult
keywords: Dental techniques; Forensic age estimation; Root development; Socioeconomic status; Third molar