Fibrinolytic activity of human gingiva in the presence or absence of plaque bacteria

Abstract

Activators of fibrinolysis are found in the gingival connective tissue and in the sulcular epithelium. The influence of plaque bacteria and the related inflammatory reaction on the fibrinolytic activity has been evaluated in the human gingiva. An autohistographic technique was applied to sections taken from three groups of 6 specimens each: group A from clinically healthy sites with plaque index = 1 and no bleeding on probing; group B from areas with unambiguous visual signs of gingivitis, with plaque index = 2-3 and bleeding on probing; group C from sites previously treated with professional toothcleaning twice a week for 3 months and with chlorhexidine mouthrinses twice a day for the final 3 wk, in order to obtain a virtually complete elimination of the plaque bacteria. In group C the plaque index was 0 and there was no bleeding on probing. Connective tissue fibrinolytic activity was present in all the sections from the three groups. The sulcular fibrinolytic activity was observed in all the sections taken from the specimens of groups A and B. In contrast, no fibrinolytic activity was observed over the sulcular area in any section taken from the specimens of group C. Therefore, this study does not support previous claims that healthy sulcular epithelium is capable of releasing activators of fibrinolysis. It can be concluded that the presence of any amount of plaque bacteria is associated with sulcular fibrinolytic activity. Contrarily, the elimination of plaque bacteria is associated with the absence of any detectable sign of fibrinolytic activity in the gingival sulcus.