Development of a Biochemical Profile for Gingival Crevicular Fluid: Methodological Considerations and Evaluation of Collagen‐Degrading and Ground Substance‐Degrading Enzyme Activity during Experimental Gingivitis

Abstract
The potential application of gingival crevicular fluid (GCF) analysis to periodontal diagnosis has been examined for more than 25 years. Unfortunately, the information available has not provided the clinician with a more sensitive means of diagnosing periodontal disease or an effective means of monitoring periodontal therapy. A careful review of the literature on GCF, however, suggests that discrepancies occur in the method of GCF collection, the use of GCF for analysis from pooled or isolated crevicular locations, the method of analyzing the samples and the way in which the data is reported. Studies in our laboratory have suggested a technique for GCF analysis that collects GCF from individual crevices with a filter paper strip inserted for a standard time, determines the volume of GCF collected with a calibrated electronic meter and elutes the material into a larger volume of diluent. This approach allows for detection of site-to-site and patient-to-patient differences in GCF volume while providing sufficient samples to analyze GCF for multiple constituents. We have used this approach to evaluate GCF for vertebrate forms of the enzymes collagenase (latent and active forms), β-glucuronidase and arylsulfatase during the development of experimental gingivitis in man. Interproximal and midradicular areas were studied. Our results indicate that during the 4 weeks of the gingivitis, the absolute amount of active collagenase in GCF increased 550% at the interproximal sites and 190% in the midradicular sites, and the per cent of active collagenase increased from 15 to 71% at the interproximal sites, and from 16 to 36% at the midradicular sites. In contrast, the increase in ground substance-degrading enzyme activity during the experimental gingivitis was proportionally less. The increase in β-glucuronidase activity in GCF was 180% for the interproximal sites and 40% for the midradicular sites, and the increase in arylsulfatase activity in GCF was 240% for the interproximal sites and 20% for the midradicular sites. These data suggest that the degree of collagen degradation in the periodontium may be modulated by a relative lack of ground substance-degrading enzyme activity in the gingival environment. In addition, this study supports the use of our sampling and processing approach for GCF analysis.