title: Immunohistological characterization of newly formed tissues after regenerative procedure in immature dog teeth.
abstract: BACKGROUND
  In a previous report, we showed that 2 types of mineralized tissues were formed in the canal spaces of dogs after tissue engineering treatments of immature teeth with apical periodontitis: (1) dentin- associated mineralized tissue (DAMT) and (2) bony islands (BIs). The objective of this study was to characterize these mineralized tissues.
  
  
  METHODS
  The maturation and organization of collagen matrices in DAMT, BIs, and the interface between DAMT and the dentin wall were characterized using a histochemical method with picrosirius red staining under polarized light microscopy. In addition, the distribution of 2 noncollagenous proteins (ie, dentin sialoprotein and bone sialoprotein) in these tissues was investigated by immunohistochemical methods with specific antibodies.
  
  
  RESULTS
  The results showed that DAMT is distinct from dentin, bone, or BIs. Although it resembled cementum to an extent showing similar immunoreactivity to the noncollagenous proteins, the organization and maturation of collagen matrix was significantly different from cementum. BIs resembled a bone matrix in terms of morphology, collagen organization, and immunoreactivity.
  
  
  CONCLUSIONS
  The results indicate that DAMT and BIs formed in the canal space are distinct from each other, one exhibiting a unique mineralized tissue and the other a bone-like tissue.
authors.affiliation: Department of Endodontics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.
authors.forename: Nozomu
authors.initials: N
authors.lastname: Yamauchi
authors.forename: Hideaki
authors.initials: H
authors.lastname: Nagaoka
authors.forename: Shizuko
authors.initials: S
authors.lastname: Yamauchi
authors.forename: Fabricio B
authors.initials: FB
authors.lastname: Teixeira
authors.forename: Patricia
authors.initials: P
authors.lastname: Miguez
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Yamauchi
mesh_terms: D000539:Alveolar Process / Q000473:pathology; D000818:Animals; D056624:Apexification / Q000379:methods*; D001391:Azo Compounds; D001857:Bone Matrix / Q000473:pathology; D002113:Calcification, Physiologic / Q000502:physiology*; D003094:Collagen / Q000648:ultrastructure; D004396:Coloring Agents; D003238:Connective Tissue / Q000473:pathology; D003739:Dental Cementum / Q000473:pathology; D003786:Dental Pulp Cavity / Q000473:pathology*; D003804:Dentin / Q000473:pathology*; D004285:Dogs; D016326:Extracellular Matrix Proteins / Q000032:analysis; D048091:Guided Tissue Regeneration / Q000379:methods; D007150:Immunohistochemistry; D058574:Integrin-Binding Sialoprotein / Q000032:analysis; D008859:Microscopy, Polarization; D010485:Periapical Periodontitis / Q000628:therapy*; D010513:Periodontal Ligament / Q000473:pathology; D010750:Phosphoproteins / Q000032:analysis; D012795:Sialoglycoproteins / Q000032:analysis; D023822:Tissue Engineering / Q000379:methods*; D019227:Tooth Apex / Q000473:pathology*; D000099311:Dentin Sialophosphoprotein
chemical_list: D001391:Azo Compounds; D003094:Collagen; D004396:Coloring Agents; D016326:Extracellular Matrix Proteins; D058574:Integrin-Binding Sialoprotein; D010750:Phosphoproteins; D012795:Sialoglycoproteins; D000099311:Dentin Sialophosphoprotein; C009798:C.I. direct red 80