title: Cementoenamel junction of deciduous teeth: SEM-morphology.
abstract: OBJECTIVE
  The aim of this study was to investigate the cementoenamel junction of a group of 11 primary sound mandibular incisors extracted for orthodontic reasons.
  
  
  METHODS
  Eleven caries and defect-free human inferior deciduous incisors were extracted for orthodontic reasons and the cementoenamel junction was investigated by scanning electron microscopy (SEM). The types of tissue interrelations were classified in four possible categories: 1) cementum and enamel edge-to-edge, 2) cementum overlapped by enamel, 3) enamel overlapped by cementum, 4) presence of exposed dentin between enamel and cementum.
  
  
  RESULTS
  In our observations root cementum and enamel edge-to-edge interrelation was the most frequent feature observed in overall sample, root cementum overlapping enamel tissues was observed in more than one third of the cementoenamel junction area, exposed dentin was a rare observation. In few, small and rare areas enamel overlapped cementum. Further studies could determine statistical prevalence.
  
  
  CONCLUSIONS
  The cementoenamel junction of primary teeth differs from that of permanent teeth, the scarcity of gaps between cementum and enamel, the epithelial junction at the equator of the crown and the globosity of the crown are probable protective factors toward decay susceptibility.
authors.affiliation: Department of Periodontology, University of Rome La Sapienza, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Ceppi
authors.forename: S
authors.initials: S
authors.lastname: Dall'Oca
authors.forename: L
authors.initials: L
authors.lastname: Rimondini
authors.forename: A
authors.initials: A
authors.lastname: Pilloni
authors.forename: A
authors.initials: A
authors.lastname: Polimeni
mesh_terms: D002648:Child; D003739:Dental Cementum / Q000648:ultrastructure; D003743:Dental Enamel / Q000648:ultrastructure; D003804:Dentin / Q000648:ultrastructure; D006801:Humans; D007180:Incisor / Q000648:ultrastructure*; D008334:Mandible; D008855:Microscopy, Electron, Scanning; D019237:Tooth Cervix / Q000648:ultrastructure*; D014094:Tooth, Deciduous / Q000648:ultrastructure*