Gingival crevicular fluid myeloperoxidase at periodontitis sites

This investigation was undertaken to determine the relationship between the amount of the polymorphoruclear leukocye (PMN) cnzyme mycloperoxidasc (MPO) in gingival crevicular fluid (GCF) collected from periodontius sites before and after root planning and (1) gingival drsease status described by clinical indices. (2) the quantity of GCF. and (3) differential dark‐field coums of Subgingival plaque microorganisms. Similar measurements except dark‐field microbial counts, were made at sites with minimal signs of periodontal disease. Higher levels of GCF MPO occurred at periodontals sites. Reduced enzyme activity fooled instrumentation therapy. The reduced enzyme activity, however, was not specifically associated with decreases in clinical indices. GCF MPO was only weakly dependent of GCF volume Consequently a major portion of the greater GCF MPO observed before root planning reflected a characteristic of the lesion other than a difference in GCF volume. Before therapy more GCF MPO was noted at sites with a greater number of subgingival plaque microorganisms. However, there was no relationship between GCF MPO and the proportion of spirochetes, mobile and rod forms in the samples. These data support the conclusion that the quantity of GCF MPO reflects factors other than those associated with clinical parameters commonly used to assess inflammatory periodontal disease.