Subgingival distribution of periodontopathic bacteria in adult periodontitis and their susceptibility to minocycline-HCl.
The purpose of this study was to investigate the distribution of several periodontopathic bacteria in adult periodontitis, their in vitro susceptibility to minocycline-HCl, and whether the efficacy of the drug changes with a decrease in bacterial susceptibility. Twenty-one patients (43 to 75 years old) with 62 periodontal lesions from pockets > or =4 mm participated in the study. After subgingival sampling, an ointment containing 2% minocycline-HCl was applied locally to the selected pockets once a week for 4 weeks. The lesions were clinically examined after 1 and 4 weeks of administration. The distribution of the subgingival microorganisms included Capnocytophaga sputigena (37.1%), Prevotella intermedia (22.6%), Porphyromonas gingivalis (22.6%), Fusobacterium nucleatum (20.1%), Actinobacillus actinomycetemcomitans (9.7%), and Eikenella corrodens (4.8%). The distribution was complex, with 76.8% of the sites containing 1 to 3 bacterial spieces. The minimum inhibitory concentration (MIC) of minocycline-HCl for each organism showed that most were inhibited by a minocycline-HCl concentration equal to or less than the MIC for reference strains. However, some clinical strains of Prevotella intermedia seemed to exihibit low susceptibility to minocycline-HCl. There were no significant differences among sites with strains exhibiting low or normal susceptibility to minocycline-HCl. The concentration of the drug applied to deep periodontal pockets inhibited the growth of most of the microorganisms investigated in this study.
Hagiwara
S
S
Department of Periodontology, Faculty of Dentistry, Tokyo Medical and Dental University, Japan. hogiwara peri@dent.tmd.ac.jp
Takamatsu
N
N
Tominaga
Y
Y
Umeda
M
M
D000287:Administration, Topical; D000328:Adult; D000368:Aged; D016976:Aggregatibacter actinomycetemcomitans / Q000187:drug effects / Q000254:growth & development / Q000302:isolation & purification; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D002206:Capnocytophaga / Q000187:drug effects / Q000254:growth & development / Q000302:isolation & purification; D015169:Colony Count, Microbial; D016124:Eikenella corrodens / Q000187:drug effects / Q000254:growth & development / Q000302:isolation & purification; D005260:Female; D016967:Fusobacterium nucleatum / Q000187:drug effects / Q000254:growth & development / Q000302:isolation & purification; D005881:Gingiva / Q000382:microbiology*; D006090:Gram-Negative Bacteria / Q000187:drug effects / Q000254:growth & development / Q000302:isolation & purification*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008911:Minocycline / Q000008:administration & dosage / Q000627:therapeutic use*; D009824:Ointments; D010514:Periodontal Pocket / Q000188:drug therapy / Q000382:microbiology; D010518:Periodontitis / Q000188:drug therapy / Q000382:microbiology*; D016966:Porphyromonas gingivalis / Q000187:drug effects / Q000254:growth & development / Q000302:isolation & purification; D018713:Prevotella intermedia / Q000187:drug effects / Q000254:growth & development / Q000302:isolation & purification; D013753:Tetracycline Resistance
D000900:Anti-Bacterial Agents; D009824:Ointments; D008911:Minocycline