Collagen III aminoterminal propeptide in gingival crevicular fluid before and after periodontal treatment.

The amount of procollagen III aminoterminal propeptide (PIIINP) in crevicular fluid (CF) was measured from three periodontitis patients before treatment (scaling, root planing, and curettage) and 2, 5, 10, 20, and 40 days after treatment. CF was collected by placing two paper strips in each pocket for 5 s, after which the amount of fluid was measured. Control samples were collected from three subjects with minimal gingival inflammation. PIIINP was extracted into saline solution and determined by a radioimmunological method. Plaque Index, Papilla Bleeding Index, and pocket depth were recorded before and 40 days after treatment. Forty days after treatment clinical parameters indicated healing. The CF PIIINP mean concentration was 162 micrograms/l (range 0-430) in the pretreatment samples. Ten days after treatment, PIIINP mean concentration was 1400 micrograms/l (range 1000-9000). After this, the concentration gradually decreased, reaching the pretreatment level 40 days after treatment. Most of the control samples showed undetectable amounts of PIIINP. It was suggested that elevated PIIINP concentrations in CF after periodontal treatment reflected increased type III collagen synthesis in gingiva. PIIINP concentrations before treatment reflected the rate of type III collagen turnover in inflamed periodontal tissues. It was further suggested that CF PIIINP has clinical value as an indicator of the healing process of inflamed gingiva.