title: Enamel defects of human primary dentition as virtual memory of early developmental events.
abstract: OBJECTIVE
  The objectives of the present study were to investigate the prevalence and the position of enamel defects of primary teeth and hence to estimate the approximate time of an insult.
  
  
  METHODS
  121 children aged 3 to 5 years were included in the study. The Modified Developmental De-fects of Enamel Index was used to diagnose and classify the defects. The defects were categorized as hypoplasia, hypocalcification or a combination of them. Each tooth was investigated for occlusal/incisal, middle, cervical, incisomiddle, cervicomiddle and complete crown defects.
  
  
  RESULTS
  55.37% of the children were affected by enamel defects, 23.96% being categorized as hypocalcification and 22.31% as hypoplasia. The enamel defects were more abundant in maxillary primary incisors and mandibular primary canines. Minimum involvement was seen in maxillary primary second molars and mandibular primary lateral incisors. The prevalence of cervical defects in maxillary primary incisors was significantly more than the middle or incisal defects (P < 0.05). The prevalence of incisal defects in mandibular primary incisors was significantly more than the middle or cervical defects (P < 0.05).
  
  
  CONCLUSIONS
  The results revealed a considerable number of enamel defects which are multiple, symmetric and chrono-logically accordant with the estimated neonatal line in primary teeth of healthy children.
authors.affiliation: Associate Professor, Department of Pediatric Dentistry, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Naser
authors.initials: N
authors.lastname: Asl Aminabadi
authors.forename: Sina
authors.initials: S
authors.lastname: Ghertasi Oskouei
authors.forename: Firoz
authors.initials: F
authors.lastname: Pouralibaba
authors.forename: Zahra
authors.initials: Z
authors.lastname: Jamali
authors.forename: Farzaneh
authors.initials: F
authors.lastname: Pakdel