title: Doxycycline-resistant bacteria in periodontally diseased individuals after systemic doxycycline therapy and in healthy individuals.
abstract: The occurrence of doxycycline-resistant bacteria was examined in subgingival plaque and on the tonsils of 12 periodontally healthy and 12 periodontally diseased individuals. The healthy group was examined 6 times at intervals of one month. The diseased group was examined before and 1, 5, 15, 26, 39, and 52 weeks after conventional periodontal therapy supplemented with systemic doxycycline for 3 weeks. The occurrence of doxycycline-resistant bacteria in the healthy group varied on average between 2.0% and 6.6% in subgingival plaque and between 3.0% and 12.4% in the tonsil samples over a 6-month period. In the diseased group the percentage of resistant bacteria increased from 10-20 times for tonsil and subgingival plaque, respectively. About half a year after therapy the values returned to the baselines. For both groups the morphological distributions of resistant bacteria were similar and unaffected by the doxycycline therapy.
authors.affiliation: Royal Dental College, Copenhagen, Denmark.
authors.forename: N E
authors.initials: NE
authors.lastname: Fiehn
authors.forename: J
authors.initials: J
authors.lastname: Westergaard
mesh_terms: D000328:Adult; D016009:Chi-Square Distribution; D003773:Dental Plaque / Q000382:microbiology; D004318:Doxycycline / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D014066:Palatine Tonsil / Q000382:microbiology; D010510:Periodontal Diseases / Q000188:drug therapy / Q000382:microbiology*; D013753:Tetracycline Resistance
chemical_list: D004318:Doxycycline