The Anti Inflammatory Effects of Chlorohexidine, Minocycline and Doxycycline

The adjunctive use of local delivered antimicrobial drugs such as chlorohexidine (CHX), minocycline and doxycycline into the subgingival pocket as the treatment of periodotitis is widely accepted. Objectives: The aim of this study was to evaluate the effect of the anti microbial agents on the inflammatory response to heat killed P. gingivalis. Materials & Methods: 2 weeks following chamber implantation, 24 balb/c mice, in the experimental group, were given an intra-chamber challenge of P. gingivalis, followed immediately by the injection of the specific antimicrobial drug: 2000 ƒÝg/ml CHX, 1500ƒnƒÝg/ml Minocycline,1500 ƒÝg/ml Doxycycline. Saline was used as the control. ( 6 animals per treatment group). A second group of 24 animals received only the antimicrobial treatment without P. gingivalis challenge. Intra-chamber exudates were sampled at 2 and 24 hours following the challenge, and the levels of the cytokines: TNFƒÑ, IFNƒ× and IL-10 and the cell counts were evaluated. Results: Cell counts: At 2 hours post-challenge, doxycycline enhanced the leukocytes migration resulting from P. gingivalis challenge while minocycline and CHX appear to decrease cell levels. After 24 hours all the agents had lost their effect. Cytokines: All three anti microbial agents decreased the levels of the pro-inflammatory cytokines compared to a challenge with P. gingivalis alone. Both doxycycline and CHX inhibited the levels of IL-10 at 2 hours post P. gingivalis challenge, whereas minocycline appear to have had no effect. At 24 hours post-challenge CHX had lost its effect. Conclusions: The local application of these antibacterial agents modifies the inflammatory response to P. gingivalis independent of their antimicrobial effect. CHX appear to have the most marked anti-inflammatory effect, although it was relatively short lived.