MOLECULAR-FORMS AND CONCENTRATION OF FIBRONECTIN AND FIBRIN IN HUMAN GINGIVAL CREVICULAR FLUID BEFORE AND AFTER PERIODONTAL TREATMENT

A total of 23 periodontitis-affected sites from seven adults was selec ted for the study. Crevicular fluid (CF) samples were collected with p aper strips before treatment (scaling, root planing, and curettage) an d 2, 5, 10, 20, and 40 days after treatment. Each sample was eluted in to sterile saline and two aliquots were drawn for gel electrophoresis: one for fibronectin and one for fibrin analysis. Peptides were transf erred to nitrocellulose membranes, and molecules were detected by spec ific antibodies. The proportions of different molecular forms of fibro nectin and fibrin were analyzed by laser densitometry. Plaque Index, P apilla Bleeding Index, and pocket depth were recorded before and 40 da ys after treatment. Radiologic bone loss was estimated from orthopanto mograms. Two days after treatment, an increase was seen in the proport ions of intact fibronectin, fibronectin fragments larger than 70 kDa, and fibrin-positive material with a greater molecular mass than intact fibrin. Between days 5 and 10, the proportions of these large fragmen ts decreased. The highest fibronectin and fibrin concentrations were s een 10 days after treatment. These changes probably reflect degradatio n of the subgingival fibrin clot formed after treatment, and indicate resolution of the clot during the first 10 days of healing. This agree s well with previous observations of CF plasmin activity and concentra tion of collagen synthesis markers in CF after periodontal treatment, and with the histologic changes seen during periodontal healing. Resul ts of the present study, together with earlier reported findings of co llagen synthesis after periodontal treatment, also support the hypothe sis of sequential appearance of fibronectin and collagens during the p rocess of wound healing.