THE EFFECT OF CHLORHEXIDINE ON THE CONCENTRATIONS OF IMMUNE HOST MEDIATORS PRESENT IN NECROTIC PULP (A Comparative In Vivo Study)

Abstract

Periapical lesions of pulpal origin are induced as a result of activation of nonspecific inflammatory reactions as well as specific immunological reactions. The mounting of an immune response requires, in most

instances, the uptake and processing of antigen by an antigen-presenting l cell such as the macrophage and the expression of the antigen or part of it 'I on the surface membrane of this cell. This is followed by the clonal

selection of B and T cells to proliferate and mature following the reception of appropriate signals. These signals are usually multiple. They consist, in the case of the B cell, of the antigen itseU: which binds to surface immunoglobulins, together with soluble factors released from helper T cells.

The cell composition of human periapical lesions IS a mixture · consisting of T and B lymphocytes, null cells, macrophages, polymorphonuclear leukocytes, monocytes and mast cells. Cells are thus present which mediate a broad spectrum of immunological phenomena.

Inflanunatory and immune responses are initiated in the pulp tissue or periapical area when antigens are introduced into the root canal.

Evaluation of host mediators in endodontic exudates is a mean by which the nature of this response can be studied, and this analysis may ultimately provide an approach for better management of patients.