title: Effects of conservatively treated diseased cementum with or without EMD on in vitro cementoblast differentiation and in vivo cementum-like tissue formation of human periodontal ligament cells.
abstract: OBJECTIVE
  The present study aimed to evaluate the effects of conservatively treated diseased cementum on in vitro cementoblast differentiation and in vivo cementum-like tissue formation of human periodontal ligament cells (hPDLCs), and observe differential effects of enamel matrix derivative (EMD) on in vivo cementum formation by hPDLCs.
  
  
  METHODS
  Forty-eight cementum slices and 48 dentin slices were prepared from periodontitis compromised teeth, and hPDLCs were inoculated on to all root slices. Twenty-four co-cultured root slices of each group were used for mRNA expression of cementum attachment protein and CEMP1. With application of EMD, 24 co-cultured root slices (divided into groups C, D, C+E, D+E) were transplanted subcutaneously into nude mice. All root fragments were reviewed by histological analysis and immunohistochemical staining for bone sialoprotein.
  
  
  RESULTS
  mRNA expressions of cementum attachment protein and cementum protein - 1 from hPDLCs on cementum slices were statistically higher than those of dentin slices. Seven specimens of group C and 10 specimens of group C+E revealed a layer of cementum-like tissue (NFC) on surfaces of pre-existing cementum. NFC was thicker in group C+E than in group C. All NFCs were positively stained for bone sialoprotein, however, there was no NFC formation on dentin slices.
  
  
  CONCLUSIONS
  Conservatively treated diseased cementum promoted in vitro cementoblast differentiation and in vivo cementum-like tissue formation by hPDLCs, and the in vivo effect was enhanced by the presence of EMD.
authors.affiliation: Shandong Provincial Key Laboratory of Oral Biomedicine, Jinan, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Qi
authors.forename: W
authors.initials: W
authors.lastname: Feng
authors.forename: J
authors.initials: J
authors.lastname: Cai
authors.forename: Q
authors.initials: Q
authors.lastname: Sun
authors.forename: S
authors.initials: S
authors.lastname: Li
authors.forename: M
authors.initials: M
authors.lastname: Li
authors.forename: A
authors.initials: A
authors.lastname: Song
authors.forename: P
authors.initials: P
authors.lastname: Yang
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D002478:Cells, Cultured; D003739:Dental Cementum / Q000166:cytology* / Q000473:pathology; D003743:Dental Enamel / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D008969:Molecular Sequence Data; D010513:Periodontal Ligament / Q000166:cytology* / Q000637:transplantation*; D010518:Periodontitis / Q000473:pathology / Q000601:surgery / Q000628:therapy*; D014092:Tooth Root / Q000166:cytology / Q000637:transplantation*