Comparative evaluation of effects of chlorhexidine and tetracycline on neutrophil viability and functions in vitro

Chlorhexidine (CHX) and Tetracycline (TET) are the two antimicrobial agents used in the management of periodontal infections, due to their antimicrobial potency and substantivity. The benefits and limitations of an antimicrobial agent can only be assessed by determining their relative toxicity to microbes and host cells.

(1) To detect the effects of CHX and TET on neutrophil viability and functions in vitro. (2) To compare the effects of CHX and TET on crevicular blood neutrophils.

Crevicular blood was collected using 5-μl pipette, stored in EDTA-containing vacutainers and sent for evaluation of Cell Viability- Neutrophils would be mixed with 0.25 volume of 0.4% trypan blue in Hank's balanced salt solution (HBSS) and counted to assess the viability. Chemotaxis- Evaluated under agarose slides, a total of 100 μl crevicular blood Neutrophils-0.2% BSA or HBSS-0.2% containing concentration of CHX and TET. Oxidative Metabolism- would be assessed using nitro blue tetrazolium. In all experiments, three concentrations of TET (0.1%, 0.05%, 0.025%) and CHX (0.01%, 0.005%, 0.0025%) respectively were used. N-Formyl methionyl leucyl phenylalanine (1 μm) in the presence of 2 μg/ml cytochalasin B will be used as the activating agent. Neutrophils would be treated with CHX and TET similarly to that for chemotaxis.

TET comparatively has less deleterious effects on neutrophil functions as compared with that of CHX with statistically significant results for all parameters tested.

From this study, it is inferred that CHX and TET do cause certain changes in neutrophil functions.