title: Bacteria recovered from teeth with apical periodontitis after antimicrobial endodontic treatment.
abstract: Chávez de Paz LE, Dahlén G, Molander A, Möller A, Bergenholtz G. Bacteria recovered from teeth with apical periodontitis after antimicrobial endodontic treatment. International Endodontic Journal, 36, 500-508, 2003.
  
  
  OBJECTIVE
  To determine whether there is a pattern for certain bacteria to remain after chemo-mechanical treatment of root canals in teeth with apical periodontitis.
  
  
  METHODS
  Consecutive root-canal samples of 200 teeth receiving root-canal treatment, referred from general practitioners and endodontic specialists for analyses of cultivable microbes, were studied prospectively. To be included, samples had to be taken at a treatment session subsequent to the one at which endodontic therapy was initiated. All samples were from teeth that either presented with clinical or radiographic evidence of apical periodontitis or both. Bacteriological findings were linked to clinical and radiographic parameters including status of the root canal prior to treatment, namely, vital pulp, necrotic pulp or root filled.
  
  
  RESULTS
  A total of 248 strains were isolated from 107 teeth giving bacterial growth. Gram-positives predominated (85%). Lactobacillus spp. (22%), nonmutans streptococci (18%), and Enterococcus spp. (12%) were the most common isolates. Gram-negative anaerobes were relatively sporadic. Large radiographic bone lesions, persistent pain and use of intracanal calcium hydroxide dressing correlated with bacterial presence (P < 0.05).
  
  
  CONCLUSIONS
  Once established, nonmutans streptococci, enterococci and lactobacilli appear to survive commonly following root-canal treatment of teeth with clinical and radiographical signs of apical periodontitis.
authors.affiliation: Departments of Oral Microbiology and Endodontology/Oral Diagnosis, Faculty of Odontology, Sahlgrenska akademin, Göteborg University, Gothenburg, Sweden. Luis.Chavez.de.Paz@odontologi.gu.se
authors.forename: L E
authors.initials: LE
authors.lastname: Chávez De Paz
authors.forename: G
authors.initials: G
authors.lastname: Dahlén
authors.forename: A
authors.initials: A
authors.lastname: Molander
authors.forename: A
authors.initials: A
authors.lastname: Möller
authors.forename: G
authors.initials: G
authors.lastname: Bergenholtz
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001419:Bacteria / Q000145:classification*; D002126:Calcium Hydroxide / Q000627:therapeutic use; D016009:Chi-Square Distribution; D003782:Dental Pulp / Q000382:microbiology; D003786:Dental Pulp Cavity / Q000382:microbiology; D003790:Dental Pulp Necrosis / Q000382:microbiology; D004202:Disinfectants / Q000627:therapeutic use; D016983:Enterococcus / Q000145:classification; D005260:Female; D006094:Gram-Positive Bacteria / Q000145:classification; D006801:Humans; D007778:Lactobacillus / Q000145:classification; D008297:Male; D008875:Middle Aged; D010485:Periapical Periodontitis / Q000382:microbiology* / Q000628:therapy; D011446:Prospective Studies; D012388:Root Canal Irrigants / Q000627:therapeutic use; D012390:Root Canal Therapy; D013291:Streptococcus / Q000145:classification
chemical_list: D004202:Disinfectants; D012388:Root Canal Irrigants; D002126:Calcium Hydroxide