Hydroxyproline titers in gingival crevicular fluid

Arginine and glutamate levels in the gingival crevicular fluid from patients with chronic periodontitis

The objectives of this study were to determine arginine and glutamate levels in the gingival crevicular fluid (GCF) of adult chronic periodontitis patients versus periodontally healthy controls, and to compare two kinds of microdialysis probes: normal and U-shaped probes. The analysis of GCF components was developed to improve the diagnosis of periodontal disease (PD). Proteolysis in the periodontal tissues increases the concentration of amino acids (aa) in the GCF and the levels of these aa may reveal PD features and stages. GCF samples were collected by microdialysis in situ from 5 periodontally affected sites (probing depth >or=5 mm, clinical attachment loss >or=3 mm) in 14 adult chronic periodontitis patients and from 14 adult periodontally healthy controls. Capillary zone electrophoresis coupled to laser induced fluorescence detection was used to measure concentration of arginine and glutamate in the GCF. Data were analyzed statistically by ANOVA and Tukey's post-hoc tests (á=0.05). Arginine concentration was increased (p<0.001) and glutamate concentration was decreased (p<0.001) in chronic periodontitis patients as compared to controls. There were no significant differences (p=0.069) between the normal and U-shaped probes. In conclusion, the increase of arginine and decrease of glutamate concentration in GCF were associated to the presence of periodontitis, and might be used as markers to recognize periodontally susceptible subjects as well as to evaluate the treatment course.

Elevated levels of collagen cross-link residues in gingival tissues and crevicular fluid of teeth with periodontal disease

Lysylpyridinoline (LP) and hydroxylysylpyridinoline (HP) are collagen cross-link residues. Lysylpyridinoline is present in most tissues, whereas LP is present mainly in mineralized tissue. Both are elevated in tissue with increased collagen resorption. The purpose of this investigation was to assess if the concentrations of LP and HP are elevated in gingiva and gingival crevicular fluid (GCF) of teeth with advanced periodontitis (AP). We investigated human gingival biopsies of healthy teeth (n = 19) and teeth with AP (n = 43) in 49 individuals. Samples of GCF from 54 teeth with AP were collected in seven patients and compared with samples from 11 patients with experimentally induced gingivitis. Levels of LP and HP were measured by HPLC and fluorescence detection. Gingival concentrations of HP but not LP around teeth with advanced periodontitis were significantly elevated compared with teeth with healthy periodontium. While significant amounts of HP and LP were measurable in the GCF of teeth with AP, no HP and LP was identified 3 months following non-surgical periodontal therapy of the teeth or in fluid from teeth subjected to experimentally induced gingivitis. Elevated concentrations of HP and LP in GCF may serve as indicators of ongoing destruction of periodontal tissues and alveolar bone in advanced periodontitis.

Human gingival crevicular fluid keratin at healthy, chronic gingivitis and chronic adult periodontitis sites

The present study was designed to determine, in a cross-sectional study, whether there was any relationship between the keratin-positive material in gingival crevicular fluid and the clinical periodontal status. Keratins were selected as putative indicators of degradation of epithelial cells cytoskeletal proteins. Keratin positive material was determined by enzyme-linked immunosorbent assay in 42 subjects exhibiting clinical sites of health, chronic gingivitis and chronic periodontitis. The concentration of keratin in parotid saliva was also measured for each subject. Keratin concentration in gingival crevicular fluid samples was significantly greater at sites exhibiting signs of gingivitis and periodontitis compared with healthy sites. No differences were detected between sites exhibiting gingivitis and periodontitis. No differences were found between the 3 groups for the saliva keratin-positive material which was significantly less than that detected in gingival crevicular fluid. These results suggest that gingival crevicular fluid keratin concentration may serve as a marker of gingival damage.

Turnover in periodontal connective tissues: dynamic homeostasis of cells, collagen and ground substances

The connective tissues of the periodontium are composed of two soft tissues and two hard tissues--each of which has unique features. This review considers the constituents of normal, healthy periodontal connective tissues together with an appraisal of the changes in the connective tissue matrices of the periodontium which occur during the development of periodontitis. Recent developments in this field have paved the way for new and exciting vistas in periodontal diagnosis and regeneration which, ultimately, are two important goals in periodontal therapy.

Gingival crevicular fluid: biomarkers of periodontal tissue activity

The lack of precise clinical criteria for assessment of periodontal disease has led to a search for alternative means of determining active disease sites, prognosis of future sites of breakdown, and response to therapy. This review highlights the potential array of biomarkers present in gingival crevicular fluid and which may relate to existing or predicted tissue regions undergoing metabolic change and derived from bacterial or host-cell-derived products. Among the former may be listed endotoxin, amines, butyrate, and a variety of enzymes and their inhibitors, such as trypsin-like proteases and bacterial collagenase. Arising from host cells is a variety of leucocytic hydrolase enzymes, lactoferrin, and lysozyme. These appear to be useful inflammatory markers and may be distinguished from products of connective tissue breakdown which include collagenous and non-collagenous products, including collagen peptides, osteonectin, and fibronectin. The proteoglycans have found particular favor as biomarkers of possible bone-resorptive activity. Attention has also been directed at the immune response, including comment on immunoglobulins, complement, eicosanoids, and cytokines. This review lists available information on the presence of these in gingival sulcus fluid and wherever possible relates their presence to disease activity.

Five parameters of gingival crevicular fluid from eight surfaces in periodontal health and disease

Volume and amounts of myeloperoxidase (MPO), lactoferrin (LF), aryl sulfatase (AS) and lactate dehydrogenase (LDH) were measured in gingival crevicular fluid (GCF) collected from the mesial and distal proximal surfaces of the premolars and first and second molars of 3 subject groups. Group assignment was based on subject mean gingival index (GI) and probing depth (PD) of sampled sites as follows: healthy, GI less than or equal to 0.5, PD less than or equal to 3.0; disease 1, GI greater than or equal to 1.0, PD greater than or equal to 3.0 mm; disease 2, PD greater than or equal to 4.0 mm. Attachment loss (ATL) of most sites in the 3 groups was: healthy, 0-1 mm; disease 1, 1-2 mm; and disease 2, 4-9 mm. GCF volume differed among surfaces and teeth in each of the 3 groups. The greater amount of GCF collected from posterior locations was not related to the GI and PD. Differences with sampling location in amounts of GCF constituents were restricted to MPO and LF. Most of these differences (greater amounts at posterior sites) were associated with more severe disease. Variability in amount and composition of GCF collected from different sites, therefore, should be considered in experiments which include quantitation of GCF parameters. The ratio of MPO in disease group 2 to disease group 1 was greater than similar ratios for GCF volume and LF, AS and LDH. The quantity of MPO was the only measure which differed between the 2 disease groups at all surfaces. MPO thus appears to have the greatest potential, among the measured parameters, to serve as a marker for advanced periodontal disease.

Diagnosis of periodontal diseases

This paper reviews current (Fall, 1990) information related to the diagnosis of periodontal diseases. As background, principles of diagnostic decision-making and conceptual shifts during the 1970's and 1980's are reviewed in brief. "Diseases" that appeared in many classification schemes for periodontal diseases in the early 1970's--for example, "periodontosis" and "occlusal trauma"--do not appear in most current classifications. A recent (1989a) classification recommended by the American Academy of Periodontology holds that "periodontitis" includes several different diseases. There is, indeed, evidence for several different forms of periodontitis, but the AAP's classification does not conform to the principles of diagnostic decision-making because of the significant overlap between and heterogeneities within its suggested "diseases". An alternative classification is suggested, based on a concept that the periodontal diseases are mixed infections whose outcome is modified by relative effectiveness of host response. This view suggests that the most usual forms, gingivitis and adult periodontitis, normally occur in persons with essentially normal defense systems. Variation in extent or severity of disease can be understood as a function of the local infection in hosts with various degrees of compromised resistance to the infection. Early-onset periodontitis (EOP) cases could be accounted for by those where host response is abnormal to some significant degree. The greater the abnormality, the greater the extent and severity of disease might be. Localized EOP cases would be those where a relatively effective specific response intervenes to ameliorate progress of disease after the initially rapid progression. Other issues are detection of disease activity and assessment of risk for disease progression. Non-cultural bacteriological tests are available, but have not yet been shown to detect or predict activity or risk. One difficulty in reaching such proof for those or other tests has been the lack of an appropriate "gold standard" for disease activity or progression. This is being remedied by development of improved automated probes and imaging technologies. Considerable effort is being devoted to determining whether factors in gingival crevicular fluid may have diagnostic utility. More evidence is needed before clinical utility is known, but several enzymes and cytokines have potential for aiding diagnostic decisions.

Periodontal diagnosis in the 1990s

Clinicians are usually inclined to reduce data obtained from diagnosis to a simpler form such as "yes or no" answers in order to obtain useful parameters for daily practice. It should be realized, however, that the diagnostic process very rarely exhibits "black and white" situations. Rather the evaluation of numerous "grey levels" is imperative. The diagnostic process, therefore, remains always incomplete and inaccurate, and it represents an evaluation of probabilities rather than certainties. For this reason, the diagnostician should realize and understand the mathematical relations between the information provided by diagnostic tests and the clinical situation actually present at the time of the test. This will allow one to convert diagnostic results into therapeutic procedures with a high degree of confidence. Since results from diagnostic tests are quite often used to decide on treatment, complex data are reduced to simple dichotomy, such as presence or absence of disease, normal or abnormal conditions, etc. In order to react to diagnostic tests in an ordinal, dichotomous manner, the clinician has to choose a particular level of a test at which he initiates treatment without having the assurance that this level represents the one and only standard at which treatment has to be initiated.

A longitudinal study of aspartate aminotransferase in human gingival crevicular fluid

Previous studies have shown that aspartate aminotransferase (AST), an established serum marker for cardiac and liver damage in humans, appears in elevated concentrations in samples of gingival crevicular fluid (GCF) from ligated vs. non-ligated teeth in beagle dogs and in elevated quantities in cross-sectional GCF sampling, adjusted for collection time, from human sites with clinical signs of past or present periodontal disease as compared to healthy sites. This paper describes a longitudinal study in which AST was monitored quarterly over a 2-year period at 2 sites/tooth in 31 patients with mild to moderate adult periodontitis. In this study sample, 40 (2.6%) of 1536 sites exhibited confirmed loss of at least 2 mm of attachment during the 2-yr observation period. In comparison with healthy sites within the same patients, AST standardized to a 30-second collection interval (AST30) was elevated at these sites with new confirmed attachment loss, and at sites with past attachment loss or gingivitis in the absence of periodontitis. When both within- and between-patient variation were taken into account, observed odds-ratios associating enzyme with disease were higher for sites with new attachment loss (9-16 depending on test cut-point) than for sites with pre-study attachment loss (3-12), or gingivitis in the absence of periodontitis (5-8). AST in GCF is strongly related to human periodontal disease. The data are consistent with the hypothesis that the relationship is strongest during episodes of cumulative tissue breakdown, but the small numbers of sites with confirmed attachment loss during the study period, or with gingivitis in the absence of periodontitis, means that further clinical studies are necessary to clarify this issue.

A cross-sectional analysis of aspartate aminotransferase in human gingival crevicular fluid

Previous investigation has shown that the concentration of aspartate aminotransferase (AST), an established serum marker for cardiac and liver damage in humans, is significantly elevated in samples of gingival crevicular fluid (GCF) from ligated teeth in beagle dogs. This paper reports on a cross-sectional study of the relationships between AST in GCF and clinical indices of human periodontal disease in 60 patients with mild to moderate adult periodontitis. AST standardized to a 30-second collection interval (AST30) showed substantial (multiple regression R2 = 0.61) association with summary indices of patient disease status, modest association (partial R2 = 0.22) with tooth disease status within patient, and weaker (partial R2 = 0.12) but statistically significant association with site-to-site variation in disease at the same tooth. AST concentration showed modest (R2 = 0.30) between-patient relationship with clinical indices, but no clinically significant relationship with these indices between sites within patients, suggesting a rough proportionality between accumulated enzyme and GCF volume at sites with varying stages of disease. The relationship between GCF volume and probing depth also appears central to interpretation of enzyme assays. Clinical measures of past periodontitis and current inflammatory disease are cross-sectionally related to variation in AST30, across patients and sites within the same patient. Considerable residual variation, especially elevated AST30 in the absence of clear signs of disease, may result from varying levels of current disease activity, not reflected in clinical measures.

Repeated measurement of crevicular fluid parameters at different sites

Few systematic studies have been made of amounts or of the composition of gingival crevicular fluid (GCF) from different sites or of the stability of GCF parameters over time. These data are needed to better understand the relation of GCF composition to periodontal health status. This report gives the volume and the amounts of lactate dehydrogenase (LDH), aryl sulfatase (AS) and neutrophil elastase (NE) for GCF collected from 6 samplings of 6 standard gingival sites in 11 young adult subjects over a 6-week period. Attachment loss (3 mm) was noted at only 1 of the 66 sites. The mean gingival index of the 11 subjects ranged from 0.33 to 1.67. The GCF volume and activity/sample of LDH and AS but not NE differed among subjects. However, differences among subjects were not found when the GCF enzyme activities were expressed as activity/microliter GCF. GCF volume and LDH, AS and NE activity all differed among the 6 sites when the activities were expressed as either quantity/sample or microliter GCF. These data show that differences among sites must be carefully considered in evaluation of GCF data. Fluid volume and LDH, AS and NE activity all varied from sampling to sampling. However, differences among sites were retained throughout the experimental period.

Detection of high-risk groups and individuals for periodontal diseases: laboratory markers from analysis of gingival crevicular fluid

Gingival crevicular fluid is regarded as a promising medium for the detection of markers of periodontal diseases activity. The collection protocols are straight forward and non-invasive and can be performed at specific sites of interest in the periodontium. Because the fluid accumulates at the gingival margin, it will contain potential markers derived not only from the host tissues and serum but also the subgingival microbial plaque, and thus an extremely broad range of candidate molecules may be investigated. However, the ability to successfully describe indicators of current disease activity and predictors of future disease is dependent not only upon the choice of the biochemical marker but also on the accurate description of the health status of the sample sites using currently available clinical and radiographic methods. Areas of study which currently show the most promise involve the analysis of host enzyme activities directed against components of the extracellular matrix, the nature of the glycosaminoglycans released into the sulcus and the concentration in gingival crevicular fluid of certain mediators of the inflammatory process, most notably prostaglandin E2.