Human tooth development Molar (tooth) Tooth decay adelaide dental school craniofacial biology dental dental features dental morphology dentition dizygotic epigenetic factors fraternal twins genetic expression genetic factors heritability history of twin research identical twins longitudinal study melbourne dental schoolcentre for orio-facial research and learning mirror imaging model-fitting monozygotic next-generation sequencing oral health path analysis permanent teeth primary teeth sexual dimorphism teeth thema EDItEUR::J Society and Social Sciences::JH Sociology and anthropology::JHM Anthropology