title: Identification of cultivable microorganisms from root canals with apical periodontitis following two-visit endodontic treatment with antibiotics/steroid or calcium hydroxide dressings.
abstract: The study was aimed at comparing the efficacy of disinfection of root canals with periapical radiolucencies when treated with either antibiotics/steroid medicaments (Ledermix or Septomixine) or a calcium hydroxide paste (Calasept). Microbiological samples were taken before and after two-visit endodontic treatment from 88 canals with apical periodontitis. All of the canals but one (87 of 88) had cultivable growth before treatment. After dressing with Ledermix, Septomixine, or Calasept, the percentages of canals remained with positive growth were 48% (13 of 27), 31% (8 of 26), and 31% (11 of 35), respectively. The chi(2) tests showed there were no significant differences in the number of canals with positive growth or mean colony forming units counts after instrumentation, irrigation and dressing. In the Ledermix group, 38 strains of bacteria were recovered. The Septomixine group had 25 strains, and the Calasept group had 25 strains. Gram-positive facultative anaerobic cocci (including staphylococci and streptococci) were more prevalent than the Gram-negative obligate anaerobic rods after treatment in all three groups. Similarities in the reduced number of canals with residual growth, and the prevalence of Gram-positive facultative anaerobic cocci suggest that the use of different inter-appointment dressings produced similar microbiological outcomes. However, factors other than the antimicrobial effectiveness of intracanal medicaments may also be responsible for the results observed.
authors.affiliation: Faculty of Dentistry, The University of Hong Kong, Prince Philip Dental Hospital, 34 Hospital Road, Hong Kong, China. cschu@hkucc.hku.hk
authors.forename: Frederick C S
authors.initials: FC
authors.lastname: Chu
authors.forename: W Keung
authors.initials: WK
authors.lastname: Leung
authors.forename: Peter C S
authors.initials: PC
authors.lastname: Tsang
authors.forename: Tak W
authors.initials: TW
authors.lastname: Chow
authors.forename: Lakshman P
authors.initials: LP
authors.lastname: Samaranayake
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001421:Bacteria, Anaerobic / Q000187:drug effects* / Q000302:isolation & purification; D002122:Calcium Chloride; D002126:Calcium Hydroxide / Q000494:pharmacology; D015169:Colony Count, Microbial; D003707:Demeclocycline / Q000494:pharmacology; D003786:Dental Pulp Cavity / Q000382:microbiology*; D004338:Drug Combinations; D006090:Gram-Negative Bacteria / Q000187:drug effects; D006094:Gram-Positive Bacteria / Q000187:drug effects; D006801:Humans; D009355:Neomycin / Q000494:pharmacology; D010485:Periapical Periodontitis / Q000382:microbiology*; D011112:Polymyxin B / Q000494:pharmacology; D011189:Potassium Chloride; D012388:Root Canal Irrigants / Q000494:pharmacology*; D017693:Sodium Bicarbonate; D012965:Sodium Chloride; D014222:Triamcinolone Acetonide / Q000494:pharmacology; D014449:Tyrothricin / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D004338:Drug Combinations; D012388:Root Canal Irrigants; C068579:Septomixine; C036086:calcium hydroxide, calcium chloride, potassium chloride, sodium bicarbonate, sodium chloride drug combination; D014449:Tyrothricin; D012965:Sodium Chloride; D003707:Demeclocycline; D011189:Potassium Chloride; C001527:Ledermix; D017693:Sodium Bicarbonate; D014222:Triamcinolone Acetonide; D009355:Neomycin; D011112:Polymyxin B; D002122:Calcium Chloride; D002126:Calcium Hydroxide