title: Revascularization and periapical repair after endodontic treatment using apical negative pressure irrigation versus conventional irrigation plus triantibiotic intracanal dressing in dogs' teeth with apical periodontitis.
abstract: OBJECTIVE
  The objective of this study was to evaluate in vivo the revascularization and the apical and periapical repair after endodontic treatment using 2 techniques for root canal disinfection (apical negative pressure irrigation versus apical positive pressure irrigation plus triantibiotic intracanal dressing) in immature dogs' teeth with apical periodontitis.
  
  
  METHODS
  Two test groups of canals with experimentally induced apical periodontitis were evaluated according to the disinfection technique: Group 1, apical negative pressure irrigation (EndoVac system), and Group 2, apical positive pressure irrigation (conventional irrigation) plus triantibiotic intracanal dressing. In Group 3 (positive control), periapical lesions were induced, but no endodontic treatment was done. Group 4 (negative control) was composed of sound teeth. The animals were killed after 90 days and the maxillas and mandibles were subjected to histological processing. The sections were stained with hematoxylin and eosin and Mallory Trichrome and examined under light microscopy. A description of the apical and periapical features was done and scores were attributed to the following histopathological parameters: newly formed mineralized apical tissue, periapical inflammatory infiltrate, apical periodontal ligament thickness, dentin resorption, and bone tissue resorption. Intergroup comparisons were done by the Kruskal-Wallis and Dunn's tests (alpha = 0.05).
  
  
  RESULTS
  Although statistically significant difference was found only for the inflammatory infiltrate (P < .05), Group 1 presented more exuberant mineralized formations, more structured apical and periapical connective tissue, and a more advanced repair process than Group 2.
  
  
  CONCLUSIONS
  From the histological observations, sodium hypochlorite irrigation with the EndoVac system can be considered as a promising disinfection protocol in immature teeth with apical periodontitis, suggesting that the use of intracanal antibiotics might not be necessary.
authors.affiliation: Department of Paediatric Dentistry, Preventive and Community Dentistry, Dental School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil. lea@forp.usp.br
authors.forename: Lea Assed Bezerra
authors.initials: LA
authors.lastname: da Silva
authors.forename: Paulo
authors.initials: P
authors.lastname: Nelson-Filho
authors.forename: Raquel Assed Bezerra
authors.initials: RA
authors.lastname: da Silva
authors.forename: Daniel Silva Herzog
authors.initials: DS
authors.lastname: Flores
authors.forename: Carlos
authors.initials: C
authors.lastname: Heilborn
authors.forename: James D
authors.initials: JD
authors.lastname: Johnson
authors.forename: Nestor
authors.initials: N
authors.lastname: Cohenca
mesh_terms: D016301:Alveolar Bone Loss / Q000473:pathology; D000539:Alveolar Process / Q000473:pathology; D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D002939:Ciprofloxacin / Q000008:administration & dosage / Q000627:therapeutic use; D003238:Connective Tissue / Q000473:pathology; D003786:Dental Pulp Cavity / Q000473:pathology; D003804:Dentin / Q000473:pathology; D003809:Dentin, Secondary / Q000473:pathology; D004285:Dogs; D004338:Drug Combinations; D008795:Metronidazole / Q000008:administration & dosage / Q000627:therapeutic use; D008911:Minocycline / Q000008:administration & dosage / Q000627:therapeutic use; D018919:Neovascularization, Physiologic / Q000502:physiology*; D010485:Periapical Periodontitis / Q000628:therapy*; D010486:Periapical Tissue / Q000098:blood supply*; D010513:Periodontal Ligament / Q000473:pathology; D011312:Pressure; D012387:Root Canal Filling Materials / Q000627:therapeutic use*; D012388:Root Canal Irrigants / Q000008:administration & dosage / Q000627:therapeutic use*; D018915:Root Canal Preparation / Q000379:methods*; D012391:Root Resorption / Q000473:pathology; D012973:Sodium Hypochlorite / Q000008:administration & dosage / Q000627:therapeutic use; D007507:Therapeutic Irrigation / Q000379:methods; D019227:Tooth Apex / Q000473:pathology; D014945:Wound Healing / Q000502:physiology
chemical_list: D000900:Anti-Bacterial Agents; D004338:Drug Combinations; D012387:Root Canal Filling Materials; D012388:Root Canal Irrigants; D008795:Metronidazole; D002939:Ciprofloxacin; D012973:Sodium Hypochlorite; D008911:Minocycline