Dental enamel defects in German medieval and early-modern-age populations

Aim of this study was to investigate the frequency and type of developmental defects of enamel (DDE) in a medieval and an early-modern-age population from Thuringia, Germany. Sixty-six skeletons subdivided into 31 single burials (12^th/13^th c.) and 35 individuals buried in groups (15^th/16^th c.) were examined. DDE were classified on 1,246 teeth according to the DDE index. Molar-incisor-hypomineralisation (MIH), a special type of DDE, was recorded according to the European Academy of Paediatric Dentistry (EAPD) criteria. DDE was found in 89.4% of the individuals (single burials 90.3% and group burials 88.6%). Hypoplastic pits were the most frequent defect in primary teeth and linear enamel hypoplasia (LEH) in permanent teeth. 13 individuals (24.1%) showed at least one hypomineralised permanent tooth, 12.2% had MIH on at least one first permanent molar and 10.0% in permanent incisors. Second primary molars were affected in 8.0% of the children and juveniles. No individual suffered from affected molars and incisors in combination. Endogenous factors like nutritional deficiencies and health problems in early childhood could have been aetiological reasons of DDE and MIH. The frequency of DDE and MIH might have been masked by extended carious lesions, dental wear and ante-mortem tooth loss.