title: Bacterial status in root-filled teeth exposed to the oral environment by loss of restoration and fracture or caries--a histobacteriological study of treated cases.
abstract: OBJECTIVE
  To describe histological and microbiological findings in teeth where root fillings had been exposed to caries and the oral environment for a prolonged period.
  
  
  METHODS
  For inclusion in the study, only teeth with a follow-up period of 3 years or more and those that had been without proper restoration for at least a period of 3 months were considered. Some root fillings had been without restoration for several years. In all, 39 roots representing 32 teeth were examined by histology.
  
  
  RESULTS
  The majority of the specimens were without a discernible periapical bone lesion as assessed by radiography. Osteolytic lesions were seen with five roots. Longitudinal tissue sections stained with a modified Brown/Brenn staining technique revealed presence of stainable bacteria in abundance at the canal entrance and in dentinal tubules but were absent mid-root and apically in all but two specimens. Soft tissue attached to the root tip and in apical ramifications displayed distinct inflammatory cell infiltrates, suggesting microbial exposure in 7 of the 39 roots examined. In all other specimens, inflammatory cell infiltrates were either nonexistent or sparse and then associated with extruded sealer material.
  
  
  CONCLUSIONS
  Well-prepared and filled root canals resist bacterial penetration even upon frank and long-standing oral exposure by caries, fracture or loss of restoration.
authors.affiliation: Department of Endodontology and Oral Diagnosis, Faculty of Odontology, The Sahlgrenska Academy at Göteborg University, Sweden.
authors.forename: D
authors.initials: D
authors.lastname: Ricucci
authors.forename: G
authors.initials: G
authors.lastname: Bergenholtz
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D004396:Coloring Agents; D003731:Dental Caries / Q000382:microbiology*; D003763:Dental Leakage / Q000382:microbiology*; D003786:Dental Pulp Cavity / Q000382:microbiology*; D003793:Dental Restoration, Permanent; D003804:Dentin / Q000382:microbiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010014:Osteolysis / Q000000981:diagnostic imaging / Q000473:pathology; D010486:Periapical Tissue / Q000000981:diagnostic imaging / Q000473:pathology; D011859:Radiography; D012387:Root Canal Filling Materials / Q000737:chemistry; D012390:Root Canal Therapy; D013499:Surface Properties; D019227:Tooth Apex / Q000382:microbiology; D014082:Tooth Fractures / Q000382:microbiology*
chemical_list: D004396:Coloring Agents; D012387:Root Canal Filling Materials