The basic objective of this proposal is to identify antimicrobial agents which will be of use in the control and treatment of destructive periodontal diseases.
The specific aims are as follows: (a) to determine the antibiotic susceptibilities of bacteria associated with periodontally diseased sites, (b) to determine the concentrations achieved and maintained in gingival fluid following oral administration of certain antibiotics, and (c) to relate the antibiotic levels available in the gingival fluid to the susceptibilities of periodontal bacteria as a means of determining the expected effect of an antibiotic on the periodontal microbiota. Susceptibility profiles will be determined by using a sufficent number of representative strains of different bacterial species to obtain a profile of the susceptibilities of the species to the antibiotics tested. The bacterial species to be tested either are currently implicated as possible etiologic agents of destructive periodontal diseases or else are frequently associated with periodontally diseased sites. The minimal inhibitory concentrations of the following antibiotics: ampicillin, amoxicillin, amoxicillin/clavulanic acid, clindamycin, doxycycline, minocycline, metronidazole, tetracycline, and erythromycin, will be determined for a significant number of strains for each species by agar dilution techniques. These data will be used to evaluate the inhibitory effects of different antimicrobial agents against specific bacteria implicated or associated with destructive periodontal diseases. Gingival fluid levels will be measured following administration of recommended oral dosages of metronidazole, clindamycin, doxycycline, and amoxicillin/clavulanic acid to determine the concentrations achieved and maintained at the site of periodontal infection. These levels will be related to the MICs of these antibiotics to determine which organisms can be expected to be inhibited, in vivo, by the antibiotic at concentrations readily available in the periodontal pocket following a recommended oral dosage regimen.

Agency
National Institute of Health (NIH)
Institute
National Institute of Dental & Craniofacial Research (NIDCR)
Type
Research Project (R01)
Project #
5R01DE006070-05
Application #
3219799
Study Section
Oral Biology and Medicine Study Section (OBM)
Project Start
1981-09-01
Project End
1988-11-30
Budget Start
1986-12-01
Budget End
1987-11-30
Support Year
5
Fiscal Year
1987
Total Cost
Indirect Cost
Name
University of Florida
Department
Type
Schools of Dentistry/Oral Hygn
DUNS #
073130411
City
Gainesville
State
FL
Country
United States
Zip Code
32611
Lacroix, J M; Walker, C B (1996) Detection and prevalence of the tetracycline resistance determinant Tet Q in the microbiota associated with adult periodontitis. Oral Microbiol Immunol 11:282-8
Lacroix, J M; Walker, C B (1995) Detection and incidence of the tetracycline resistance determinant tet(M) in the microflora associated with adult periodontitis. J Periodontol 66:102-8
Walker, C B; Gordon, J M; Magnusson, I et al. (1993) A role for antibiotics in the treatment of refractory periodontitis. J Periodontol 64:772-81
Lepine, G; Lacroix, J M; Walker, C B et al. (1993) Sequencing of a tet(Q) gene isolated from Bacteroides fragilis 1126. Antimicrob Agents Chemother 37:2037-41
Lacroix, J M; Walker, C B (1992) Identification of a streptomycin resistance gene and a partial Tn3 transposon coding for a beta-lactamase in a periodontal strain of Eikenella corrodens. Antimicrob Agents Chemother 36:740-3
Lacroix, J M; Walker, C (1991) Characterization of a beta-lactamase found in Eikenella corrodens. Antimicrob Agents Chemother 35:886-91
Walker, C; Gordon, J (1990) The effect of clindamycin on the microbiota associated with refractory periodontitis. J Periodontol 61:692-8
Leung, K P; Fukushima, H; Sagawa, H et al. (1989) Surface appendages, hemagglutination, and adherence to human epithelial cells of Bacteroides intermedius. Oral Microbiol Immunol 4:204-10
Walker, C B; Pappas, J D; Tyler, K Z et al. (1985) Antibiotic susceptibilities of periodontal bacteria. In vitro susceptibilities to eight antimicrobial agents. J Periodontol 56:67-74