title: Heritability estimates of dental arch parameters in Lithuanian twins.
abstract: BACKGROUND
  The genetic influence on dental arch morphology may be country-specific, thus it is reasonable to check the estimates of genetics across different populations. The purpose of this study was to evaluate the heredity of dental arch morphology in the sample of Lithuanian twins with accurate zygosity determination.
  
  
  METHODS
  The study sample consisted of digital dental models of 40 monozygotic (MZ) and 32 dizygotic (DZ) twin pairs. The estimates of heritability (h(2)) for dental arch breadth and length were calculated.
  
  
  RESULTS
  All dental arch breadths and lengths were statistically significantly larger in men than in women. Arch length differences between genders were less expressed than largest breadth differences. In the upper jaw the largest genetic effect was found on the arch breadth between lateral incisors. The heritability of dental arch length demonstrated similar differences between upper and lower jaw with mandible dental arch length being more genetically determined.
  
  
  CONCLUSIONS
  The largest genetic impact was found on the upper dental arch breadth between lateral incisors. Similar, but lower heritability is inherent for canines and first premolars of the upper jaw and first premolars of the lower jaw. It also can be noted, that arch breadths between posterior teeth show lower heritability estimates than between anterior teeth on both jaws. The dental arch in the upper jaw has more expressed genetic component than in the lower jaw.
authors.affiliation: Clinic of Orthodontics, Medical Academy, Lithuanian University of Health Sciences, J. Lukšos-Daumanto g. 6, LT-50106 Kaunas, Lithuania. Vilma.Svalkauskiene@lsmuni.lt.
authors.forename: Vilma
authors.initials: V
authors.lastname: Švalkauskienė
authors.forename: Kastytis
authors.initials: K
authors.lastname: Šmigelskas
authors.forename: Loreta
authors.initials: L
authors.lastname: Šalomskienė
authors.forename: Irena
authors.initials: I
authors.lastname: Andriuškevičiūtė
authors.forename: Aurelija
authors.initials: A
authors.lastname: Šalomskienė
authors.forename: Arūnas
authors.initials: A
authors.lastname: Vasiliauskas
authors.forename: Antanas
authors.initials: A
authors.lastname: Šidlauskas
mesh_terms: D000293:Adolescent; D000328:Adult; D001641:Bicuspid / Q000033:anatomy & histology; D002508:Cephalometry / Q000379:methods; D003481:Cuspid / Q000033:anatomy & histology; D003724:Dental Arch / Q000033:anatomy & histology*; D005260:Female; D006801:Humans; D008097:Lithuania; D008297:Male; D008334:Mandible / Q000033:anatomy & histology; D008437:Maxilla / Q000033:anatomy & histology; D003765:Models, Dental; D012737:Sex Factors; D014429:Twins, Dizygotic / Q000235:genetics*; D014430:Twins, Monozygotic / Q000235:genetics*; D055815:Young Adult