title: Histologic study of a human immature permanent premolar with chronic apical abscess after revascularization/revitalization.
abstract: BACKGROUND
  Histologic studies of teeth from animal models of revascularization/revitalization are available; however, specimens from human studies are lacking. The nature of tissues formed in the canal of human revascularized/revitalized teeth was not well established.
  
  
  METHODS
  An immature mandibular premolar with infected necrotic pulp and a chronic apical abscess was treated with revascularization/revitalization procedures. At both the 18-month and 2-year follow-up visits, radiographic examination showed complete resolution of the periapical lesion, narrowing of the root apex without root lengthening, and minimal thickening of the canal walls. The revascularized/revitalized tooth was removed because of orthodontic treatment and processed for histologic examination.
  
  
  RESULTS
  The large canal space of revascularized/revitalized tooth was not empty and filled with fibrous connective tissue. The apical closure was caused by cementum deposition without dentin. Some cementum-like tissue was formed on the canal dentin walls. Inflammatory cells were observed in the coronal and middle third of revascularized/revitalized tissue.
  
  
  CONCLUSIONS
  In the present case, the tissue formed in the canal of a human revascularized/revitalized tooth was soft connective tissue similar to that in the periodontal ligament and cementum-like or bone-like hard tissue, which is comparable with the histology observed in the canals of teeth from animal models of revascularization/revitalization.
authors: Department of Endodontics, Faculty of Dentistry, University Santo Tomás in Bogotá, Bogotá, Colombia.
authors: Patricia
authors: P
authors: Becerra
authors: Private Practice, Cetraro, Italy. Electronic address: dricucci@libero.it.
authors: Domenico
authors: D
authors: Ricucci
authors: Private Practice, Cetraro, Italy.
authors: Simona
authors: S
authors: Loghin
authors: Department of Endodontics, New York University, New York, New York.
authors: Jennifer L
authors: JL
authors: Gibbs
authors: Department of Endodontics, New York University, New York, New York.
authors: Louis M
authors: LM
authors: Lin
mesh_terms: D017607:Aluminum Compounds / Q000627:therapeutic use; D000900:Anti-Bacterial Agents / Q000008:administration & dosage; D056624:Apexification / Q000379:methods*; D001641:Bicuspid / Q000473:pathology*; D001777:Blood Coagulation / Q000502:physiology; D002113:Calcification, Physiologic / Q000502:physiology; D017610:Calcium Compounds / Q000627:therapeutic use; D025021:Cementogenesis / Q000502:physiology; D002648:Child; D002939:Ciprofloxacin / Q000008:administration & dosage; D003238:Connective Tissue / Q000473:pathology; D003751:Dental Fistula / Q000628:therapy; D003786:Dental Pulp Cavity / Q000473:pathology; D003790:Dental Pulp Necrosis / Q000628:therapy; D003804:Dentin / Q000473:pathology; D004338:Drug Combinations; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008768:Methylmethacrylates / Q000627:therapeutic use; D008795:Metronidazole / Q000008:administration & dosage; D008911:Minocycline / Q000008:administration & dosage; D010087:Oxides / Q000627:therapeutic use; D010482:Periapical Abscess / Q000628:therapy*; D012387:Root Canal Filling Materials / Q000627:therapeutic use; D018915:Root Canal Preparation / Q000379:methods; D017640:Silicates / Q000627:therapeutic use; D019227:Tooth Apex / Q000473:pathology; D015035:Zinc Oxide-Eugenol Cement / Q000627:therapeutic use
chemical_list: D017607:Aluminum Compounds; D000900:Anti-Bacterial Agents; D017610:Calcium Compounds; D004338:Drug Combinations; D008768:Methylmethacrylates; D010087:Oxides; D012387:Root Canal Filling Materials; D017640:Silicates; D015035:Zinc Oxide-Eugenol Cement; C086631:mineral trioxide aggregate; D008795:Metronidazole; D002939:Ciprofloxacin; C031667:IRM cement; D008911:Minocycline
keywords: Bone-like tissue; cementum-like tissue; chronic apical abscess; human immature permanent tooth; revascularization/revitalization