A 2-year longitudinal study of elastase in human gingival crevicular fluid and periodontal attachment loss

Metatranscriptomic analyses of the oral microbiome

Although the composition of the oral human microbiome is now well studied, regulation of genes within oral microbial communities remains mostly uncharacterized. Current concepts of periodontal disease and caries highlight the importance of oral biofilms and their role as etiological agents of those diseases. Currently, there is increased interest in exploring and characterizing changes in the composition and gene-expression profiles of oral microbial communities. These efforts aim to identify changes in functional activities that could explain the transition from health to disease and the reason for the chronicity of those infections. It is now clear that the functions of distinct species within the subgingival microbiota are intimately intertwined with the rest of the microbial community. This point highlights the relevance of examining the expression profile of specific species within the subgingival microbiota in the case of periodontal disease or caries lesions, in the context of the other members of the biofilm in vivo. Metatranscriptomic analysis of the oral community is the starting point for identifying environmental signals that modulate the shift in metabolism of the community from commensal to dysbiotic. These studies give a snapshot of the expression patterns of microbial communities and also allow us to determine triggers to diseases. For example, in the case of caries, studies have unveiled a potential new pathway of sugar metabolism, namely the use of sorbitol as an additional source of carbon by Streptococcus mutans; and in the case of periodontal disease, high levels of extracellular potassium could be a signal of disease. Longitudinal studies are needed to identify the real markers of the initial stages of caries and periodontal disease. More information on the gene-expression profiles of the host, along with the patterns from the microbiome, will lead to a clearer understanding of the modulation of health and disease. This review presents a summary of these initial studies, which have opened the door to a new understanding of the dynamics of the oral community during the dysbiotic process in the oral cavity.

Methodological evaluation of gingival crevicular fluid volume and neutrophil elastase levels: sequential sampling, length of sampling time and two different sampling methods

Objectives: The mechanisms underlying the formation and composition of gingival crevicular fluid (GCF) and its flow into and from periodontal pockets are not understood very well. The aim of this study was to evaluate the length of sampling time and sequential sampling of GCF neutrophil elastase (NE) enzyme levels by using intracrevicular and orifice methods.Material and methods: Twenty adults (mean age of 41.8 years, ranged 31-60 years, 18 males and 2 females) with chronic periodontitis were enrolled and all completed the 3-d study. GCF was collected by both intracrevicular and intrasulcular methods, 720 samples of GCF were collected. In first, second and third day, the length of sampling time in seconds (s) and order were '5- 10-30-s'; '10- 30- 5-s' and '30- 5- 10-s,' respectively. GCF elastase levels were determined by hydrolysis of neutrophil specific substrate N-methoxysuccinyl-Ala-Ala-Pro-Val-p-nitroanilide.Results: NE activity (µU) and NE activity/volume (µU/µl) were significantly different for order of sampling (p < .05), but not for the length of sampling time (p>.05).Conclusions: Within the limits of this study, the choice of sampling technique in GCF-profile studies seems to be a critical decision as it has the potential to affect the GCF volume and NE activity.

Metatranscriptome of the Oral Microbiome in Health and Disease

The last few decades have witnessed an increasing interest in studying the human microbiome and its role in health and disease. The focus of those studies was mainly the characterization of changes in the composition of the microbial communities under different conditions. As a result of those studies, we now know that imbalance in the composition of the microbiome, also referred to as microbial dysbiosis, is directly linked to developing certain conditions. Dysbiosis of the oral microbiome is a prime example of how this imbalance leads to disease in the case of periodontal disease. However, there is considerable overlap in the phylogenetic profiles of microbial communities associated with active and inactive lesions, suggesting that the difference in periodontal status of those sites may not be explained solely by differences in the subgingival microbial composition. These findings suggest that differences in functional activities may be the essential elements that define the dysbiotic process. Researchers have recently begun to study gene expression of the oral microbiome in situ with the goal of identifying changes in functional activities that could explain the transition from health to disease. These initial results suggest that, rather than a specific composition, a better understanding of oral dysbiosis can be obtained from the study of functional activities of the microbial community. In this review, we give a summary of these initial studies, which have opened a new door to our understanding of the dynamics of the oral community during the dysbiotic process in the oral cavity.

Investigation of a Novel Predictive Biomarker Profile for the Outcome of Periodontal Treatment

BACKGROUND

An ability to predict the response to conventional non-surgical treatment of a periodontal site would be advantageous. However, biomarkers or tests devised to achieve this have lacked sensitivity. The aim of this study is to assess the ability of a novel combination of biomarkers to predict treatment outcome of patients with chronic periodontitis.

METHODS

Gingival crevicular fluid (GCF) and subgingival plaque were collected from 77 patients at three representative sites, one healthy (probing depth [PD] ≤3 mm) and two diseased (PD ≥6 mm), at baseline and at 3 and 6 months after treatment. Patients received standard non-surgical periodontal treatment at each time point as appropriate. The outcome measure was improvement in probing depth of ≥2 mm. Concentrations of active enzymes (matrix metalloproteinase [MMP]-8, elastase, and sialidase) in GCF and subgingival plaque levels of Porphyromonas gingivalis, Tannerella forsythia, and Fusobacterium nucleatum were analyzed for prediction of the outcome measure.

RESULTS

Using threshold values of MMP-8 (94 ng/μL), elastase (33 ng/μL), sialidase (23 ng/μL), and levels of P. gingivalis (0.23%) and T. forsythia (0.35%), receiver operating characteristic curves analysis demonstrated that these biomarkers at baseline could differentiate healthy from diseased sites (sensitivity and specificity ≥77%). Furthermore, logistic regression showed that this combination of these biomarkers at baseline provided accurate predictions of treatment outcome (≥92%).

CONCLUSION

The "fingerprint" of GCF enzymes and bacteria described here offers a way to predict the outcome of non-surgical periodontal treatment on a site-specific basis.

Functional signatures of oral dysbiosis during periodontitis progression revealed by microbial metatranscriptome analysis

BACKGROUND

Periodontitis is a polymicrobial biofilm-induced inflammatory disease that affects 743 million people worldwide. The current model to explain periodontitis progression proposes that changes in the relative abundance of members of the oral microbiome lead to dysbiosis in the host-microbiome crosstalk and then to inflammation and bone loss. Using combined metagenome/metatranscriptome analysis of the subgingival microbiome in progressing and non-progressing sites, we have characterized the distinct molecular signatures of periodontitis progression.

METHODS

Metatranscriptome analysis was conducted on samples from subgingival biofilms from progressing and stable sites from periodontitis patients. Community-wide expression profiles were obtained using Next Generation Sequencing (Illumina). Sequences were aligned using 'bowtie2' against a constructed oral microbiome database. Differential expression analysis was performed using the non-parametric algorithm implemented on the R package 'NOISeqBio'. We summarized global functional activities of the oral microbial community by set enrichment analysis based on the Gene Ontology (GO) orthology.

RESULTS

Gene ontology enrichment analysis showed an over-representation in the baseline of active sites of terms related to cell motility, lipid A and peptidoglycan biosynthesis, and transport of iron, potassium, and amino acids. Periodontal pathogens (Tannerella forsythia and Porphyromonas gingivalis) upregulated different TonB-dependent receptors, peptidases, proteases, aerotolerance genes, iron transport genes, hemolysins, and CRISPR-associated genes. Surprisingly, organisms that have not been usually associated with the disease (Streptococcus oralis, Streptococcus mutans, Streptococcus intermedius, Streptococcus mitis, Veillonella parvula, and Pseudomonas fluorenscens) were highly active transcribing putative virulence factors. We detected patterns of activities associated with progression of clinical traits. Among those we found that the profiles of expression of cobalamin biosynthesis, proteolysis, and potassium transport were associated with the evolution towards disease.

CONCLUSIONS

We identified metabolic changes in the microbial community associated with the initial stages of dysbiosis. Regardless of the overall composition of the community, certain metabolic signatures are consistent with disease progression. Our results suggest that the whole community, and not just a handful of oral pathogens, is responsible for an increase in virulence that leads to progression.

TRIAL REGISTRATION

NCT01489839, 6 December 2011.

Elastase and metalloproteinase-9 concentrations in saliva in patients with chronic periodontitis

Elastase and metalloproteinase-9 (MMP-9) are two of numerous proteolytic enzymes released by neutrophilic granulocytes in the course of periodontitis. The aim of the study was to determine the concentrations of elastase and MMP-9 in saliva in patients with chronic periodontitis compared to healthy individuals.

The enzyme-linked immunosorbent assay method was employed to determine the concentrations of elastase and MMP-9 in saliva in patients with chronic periodontitis and with pocket depth (PD) ≥ 6 mm and PD < 6 mm, as well as in saliva of healthy individuals. Significantly higher concentrations of elastase and MMP-9 were observed in patients with periodontitis compared to healthy individuals (p < 0.01). Also a significant difference in elastase concentration in saliva was observed between the PD ≥ 4 mm and PD < 6 mm groups and between the PD ≥ 6 mm and control groups, and statistically significant differences in MMP-9 concentrations between the PD ≥ 6 mm and control groups. No statistically significant differences were observed between the PD < 6 mm and control groups for elastase concentrations in saliva as well as between the PD ≥ 6 mm and PD < 6 mm groups, and also between the PD < 6 mm and control groups for MMP-9 concentrations in saliva. Elastase and MMP-9 concentrations in saliva can be considered as biochemical indicators of severity of periodontitis.

Host-derived diagnostic markers related to soft tissue destruction and bone degradation in periodontitis

BACKGROUND

A major challenge in clinical periodontics is to find a reliable molecular marker of periodontal tissue destruction with high sensitivity, specificity and utility.

OBJECTIVES

The aim of this systematic review is to evaluate available literature on 'the utility of molecular markers of soft and hard periodontal tissue destruction'.

MATERIALS AND METHODS

Based on the focused question, 'What is the utility of molecular markers of soft and hard periodontal tissue destruction', an electronic and manual search was conducted for human studies presenting clinical data for the potential of molecular markers of tissue destruction in biofluids; gingival crevicular fluid (GCF), saliva, and serum.

RESULTS

Papers fulfilling the inclusion criteria were selected. All relevant data from the selected papers were extracted and recorded in separate tables for molecules in GCF, saliva, and serum.

CONCLUSION

Within the defined limits of the Problem/Population, Intervention, Comparison, Outcome, the present analysis reveals that (a) no single or combination of markers exists that can disclose periodontal tissue destruction adequately; (b) while the most fruitful source of biomarkers for periodontal destruction appears to be in molecules tightly related to bone and soft tissue destruction, this remains to be objectively demonstrated. Currently, clinical measurements are still the most reliable.

Effect of systemically administered naproxen sodium on clinical parameters and myeloperoxidase and elastase-like activity levels in gingival crevicular fluid

BACKGROUND

The present study was conducted to determine the possible effect of naproxen sodium on clinical status and the enzymatic profile of gingival crevicular fluid (GCF) when given as adjunct to periodontal treatment.

METHODS

A total of 34 subjects with chronic periodontitis were selected and divided into two groups to receive either naproxen sodium or placebo. At baseline, GCF samples were obtained and probing depths (PD), gingival index (GI), plaque index (PI), and gingival bleeding index (GBI) scores were recorded. In the non-steroidal anti-inflammatory drug (NSAID) group, patients were treated with a protocol consisting of baseline periodontal treatment (scaling, root planing) and naproxen sodium (275 mg) administration daily for 6 weeks. In the placebo group, patients received the same treatment except placebo was given instead of naproxen sodium. At the end of the experimental period, clinical recordings and GCF sampling were repeated. Myeloperoxidase (MPO) and elastase-like enzyme activity (ELA) levels were determined in GCF samples by a spectrophotometric method. GCF enzymatic content was calculated both as total enzyme activity and enzyme concentration.

RESULTS

All of the clinical parameters, except mean GBI, were significantly lower in the experimental group (P <0.05). At baseline and at the end of the experimental period, there were no significant differences between the NSAID and placebo groups regarding GCF MPO and ELA levels in either mode of data presentation (P <0.05). However, in the NSAID group, mean ELA concentration (P = 0.002) and mean total ELA (P = 0.003) presented significant decreases with treatment. Also, with treatment, a general reduction in MPO levels was seen; however, this difference was not significant. Although constant and stable correlations between GCF enzyme levels and clinical parameters could not be found, positive and strong correlations were observed between total enzyme activity and enzyme concentrations.

CONCLUSION

Based on the positive clinical effect and the ELA profile of GCF, it can be suggested that NSAIDs given as an adjunct to baseline periodontal treatment could be beneficial in the outcome of treatment.

Analysis of gingival crevicular fluid as applied to the diagnosis of oral and systemic diseases

Gingival crevicular fluid (GCF), a serum transudate or inflammatory exudate, can be collected from the gingival crevice surrounding the teeth. As such, the fluid reflects the constituents of serum, the cellular response in the periodontium, and contributions from the gingival crevice. The study of GCF has focused on defining the pathophysiology of periodontal disease, and identification of a potential diagnostic test for active periodontitis. The majority of markers that have been identified as potential candidates for such a test are measures of inflammation (i.e., prostaglandin E2 (PGE2), neutrophil elastase, and the lysosomal enzyme beta-glucuronidase). Further, analysis of inflammatory markers in GCF may assist in defining how certain systemic disorders (e.g., diabetes mellitus) can modify periodontal disease, and how periodontal disease/periodontal inflammation can influence certain systemic disorders (i.e., cardiovascular/cerebrovascular diseases). Methodological concerns related to the collection and analysis of GCF are important factors that need to be considered when studying GCF. Practical concerns argue against the widespread clinical application of GCF as an adjunct to periodontal diagnosis. Rather, analysis of GCF-derived mediators in saliva may serve as a means of rapid screening for periodontal disease.

Secretory leukocyte protease inhibitor and its potential interactions with elastase and cathepsin B in gingival crevicular fluid and saliva from patients with chronic periodontitis

BACKGROUND AND OBJECTIVE

Elastase is carried into the oral cavity by gingival crevicular fluid (GCF) from periodontal lesions. Our study investigated the regulation of elastase activity by secretory leukocyte protease inhibitor (SLPI) and the possible action of another GCF protease on this protective salivary component.

MATERIAL AND METHODS

Whole-mouth saliva (WMS), parotid saliva (PS) and GCF were obtained from 19 patients with periodontitis. The concentrations of active elastase and cathepsin B were determined using peptide substrates. SLPI and alpha1-proteinase inhibitor (alpha1PI) concentrations were determined using enzyme-linked immunosorbent assays (ELISAs). The molecular forms of SLPI were examined by immunoblotting.

RESULTS

The molar concentrations of elastase, cathepsin B and alpha1PI were higher in GCF than in WMS and especially PS (p < 0.0002). The GCF SLPI concentrations were also higher than the WMS SLPI concentrations (p < 0.05). All WMS components increased with GCF content, significantly for elastase and SLPI (p < 0.002). In GCF, the concentration of alpha1PI was higher than the concentration of SLPI (p < 0.0002), while there was no significant difference for WMS. SLPI and elastase levels in GCF and WMS were inversely related (p < 0.005). In SLPI immunoblots, PS contained only the intact 14-kDa molecule of SLPI, while WMS also contained an 8-kDa fragment. For WMS there was a positive correlation between SLPI degradation and cathepsin B (p < 0.002). Incubation of WMS alone or of PS with GCF in the presence of cysteine proteinase activators caused SLPI immunoreactivity to shift to 8 kDa.

CONCLUSION

For GCF, serum-derived alpha1PI is the major elastase inhibitor, but in WMS SLPI probably reduces activity. The inflamed gingivae can be an additional source of SLPI in the oral cavity, but here the molecule is apparently cleaved by GCF cysteine proteinases, such as cathepsin B.

Periodontal disease and spontaneous preterm birth: a case control study

Background

Several studies have suggested an association between periodontal disease and prematurity but this finding has not been consistently observed.

Methods

Case control study. Cases (n = 50) were women who had delivered after spontaneous preterm labor at <35 weeks gestation. Two groups of controls (n = 101) were recruited: women who were undelivered but at a preterm gestation and women who delivered at term. A standard, clinical, periodontal examination was performed and gingival crevicular fluid was obtained from standardized locations and tested for neutrophil elastase along with the bacterial enzymes gingipain and dipeptidylpeptidase. Data were analyzed with Fisher's exact tests, ANOVA and multivariate logistic regression.

Results

There was no difference in the proportion of sites with significant attachment loss (≥3 mm): Cases-3.2%, Controls-2.2% p = 0.21. The gingival crevicular fluid concentrations of elastase and gingipain were elevated in cases vs. controls 238.8 uU/ul vs. 159.6 uU/ul p = .007 and 2.70 uU/ul vs. 1.56 uU/ul p = .001. On multivariate analysis, the mean log concentration of elastase, but not of gingipain, remained a significant predictor of preterm labor p = .0.015.

Conclusion

We found no evidence that clinical periodontal disease is associated with spontaneous preterm birth. Elevated gingival crevicular fluid levels of elastase were associated with preterm birth but further research is needed before this can be assumed to be a causal relationship.

Advances in periodontal disease markers

A computer-assisted medline search was conducted to find the relevant articles concerning the periodontal disease markers in gingival crevicular fluid (GCF) and saliva published during the 10-year period from 1993 to July 2003. This review suggests that certain diagnostic uses of saliva and GCF show promise. Although both fluids have been used to evaluate the risk for an individual to develop periodontal disease and to monitor of the host response to periodontal therapy, GCF has the chance of being closely approximated to the periodontal tissues where periodontal disease begins. The enzymes contributed to extracellular matrix (ECM) molecules and non-ECM molecules degradation and markers for polymorphonuclear leukocytes (PMN) activity and influx into the gingival tissue seem to provide valuable information regarding the periodontal disease diagnosis and prognosis. There is also an increasing evidence implicating reactive oxygen species and nitric oxide pathway in the pathogenesis of periodontal diseases. Although promising results have been achieved with the assays evaluating the markers in assessment of periodontal disease status, up to now, none of these tests are used routinely. Further, one commercially available genetic test has been reported to have the potential to be used to predict the periodontal disease, but there are controversial reports on this genetic susceptibility test.

Activation of human matrix metalloproteinase 2 by gingival crevicular fluid and Porphyromonas gingivalis

AIM

To assess the potential of gingival crevicular fluid (GCF) from adult periodontitis patients and Porphyromonas gingivalis proteases to activate matrix metalloproteinase 2 (MMP-2) in vitro.

MATERIAL AND METHODS

GCF samples were collected from each of 15 adult periodontitis patients, from a clinically healthy site, a deep (>6 mm) bleeding site, and a deep nonbleeding site. The GCF samples were examined for general proteolytic activity, gelatinolytic activity and ability to activate pro-MMP-2 by zymography. Ultrasonic extracts of a range of clinical isolates of P. gingivalis cells and purified arg- and lys-gingipains were also assessed for their ability to activate pro-MMP-2.

RESULTS

GCF from deep nonbleeding sites showed higher general proteolytic activity than samples from deep bleeding and healthy sites but this did not reach statistical significance. Pefabloc, a general serine protease inhibitor, inhibited the majority (92%) of the proteolytic activity. GCF samples contained neutrophil MMP-9 in its latent form in 93% of the samples, and in its activated form in 40% of the samples. In contrast, MMP-2 was present in only trace amounts in 9% of the samples. When latent MMP-2 was added to these GCF samples, it was converted to the activated form (59 kDa) in 68% of the samples. Lower molecular weight (55 and 45 kDa) activated forms also appeared in 53% of the samples, particularly those from deep sites. Activation to the 55 and 45 kDa forms was inhibited by MSAAPket (a neutrophil elastase inhibitor), whereas Pefabloc completely inhibited the activation of latent MMP-2. All ultrasonic extracts of P. gingivalis activated latent MMP-2 in a concentration- and time-dependent manner. Also, latent MMP-2 was activated by purified arg-gingipain but less efficiently by lys-gingipain.

CONCLUSION

These findings suggest that P. gingivalis arg-gingipain and neutrophil elastase present in GCF can activate latent MMP-2, which may contribute in vivo to local periodontal tissue destruction.

Granulocyte elastase activity in static and flow gingival crevicular fluid

OBJECTIVES

This study aimed to evaluate the volume of gingival crevicular fluid (GCF) and granulocyte elastase activity in static GCF (sGCF) and flow GCF (fGCF) from subjects with various periodontal conditions.

METHODS

Eleven periodontally healthy, 10 gingivitis and 12 periodontitis subjects were recruited and the sites investigated consisted of healthy sites from healthy subjects (HH); healthy (HG) and gingivitis sites (GG) from gingivitis subjects; and healthy (HP), gingivitis (GP) and periodontitis sites (PP) from periodontitis subjects. fGCF samples were collected either 1 min or 5 min following sGCF collection by paper strip technique. GCF volume was determined by Periotron 6000 and granulocyte elastase activity was assayed with a specific substrate [l-pyroglutamyl-l-prolyl-l-valine-p-nitroanilide(pGluProVal-pNA)].

RESULTS

At baseline, no significant differences existed in clinical and GCF parameters between the two matched sites for subsequent collection of fGCF samples either 1 min or 5 min after sGCF sampling in all subjects. The flow exudate in HG and HP sites quickly replenished to sGCF levels, while a delayed replenishment was found in HH sites, despite the similar sGCF volumes of these sites. The GCF volume and elastase levels in the fGCF at 1 min were higher in GP sites than in GG sites (P < 0.05). Overall, depletion of elastase levels in the fGCF at 1 min was observed in all subjects, whereas elastase levels in the fGCF at 5 min had replenished to sGCF levels in HP, GP, PP sites and GG sites, but had remained at a lower level in HH and HG sites. An overall positive correlation was found between sGCF and fGCF for GCF volume and elastase activity (P < 0.001); however, this correlation varied with GCF parameters and with site conditions of the subjects concerned.

CONCLUSIONS

This study shows that patterns of dynamic changes in GCF flow and elastase activity varied under different periodontal conditions. Assessment of both sGCF and fGCF may allow better insight into the dynamic change of the target components in GCF.

Preventive strategies and supportive treatment

There is a preponderance of evidence in the literature that periodontal and other oral diseases, such as caries, can be treated and controlled by thorough mechanical plaque removal by the patient, the use of antimicrobial agents and antibiotics when necessary, and participation with the therapist in a well monitored, long-range program of supportive periodontal therapy. Recent evidence suggests that the control and prevention of oral disease, especially periodontitis, is especially important for patients with various systemic conditions that can be impacted by oral infections. It is far better for patients and therapists to practice primary and even secondary prevention with effective plaque control and regular, consistent supportive periodontal therapy, than having to rely on tertiary prevention for disease that has progressed to a level that requires costly treatment, is time-consuming and carries a greater risk of morbidity.

Microassay for the detection of elastase activity in the gingival crevice

BACKGROUND, AIMS

A new microassay for the detection of elastase activity (EA) in gingival crevicular fluid (GCF) has been established. GCF was collected with Periopaper strips and quantified in a Periotron.

METHODS

Enzyme activity was measured in a microtiter plate reader, using a fluorometric assay. To ensure quality and precision of the assay, recovery rates were determined at different activities with a recovery of >90%. In a 2nd step, stability of the enzyme was investigated during storage at room temperature, +4 degrees C, -22 degrees C, -88 degrees C. GCF samples retained elastase activity of almost 100% after a storage of 3 days at -22 degrees C. In a group of 12 healthy volunteers, elastase activity was assayed throughout an 18 day experimental gingivitis protocol.

RESULTS

Median activity increased from 481 microU/microl at baseline to 1444 microU/microl at day 18, which was accompanied by the development of the signs of gingivitis. The increase of EA during the experimental phase of the study was highly significant (p<0.001) and correlated well with the increasing severity of gingivitis.

CONCLUSION

The data suggest that elastase activity in GCF is an excellent quantitative measure of gingival inflammation.

The importance of data presentation regarding gingival crevicular fluid myeloperoxidase and elastase-like activity in periodontal disease and health status

BACKGROUND

The enzymatic profile of gingival crevicular fluid (GCF) is being analyzed with increasing interest, but related studies lack a general consensus on most methodological points, including the appropriate mode of data presentation.

METHODS

GCF myeloperoxidase (MPO) and elastase-like activity (ELA) levels were spectrophotometrically determined on a total of 60 subjects who were divided into three equal subgroups as early-onset periodontitis (EOP), adult periodontitis (AP), and healthy. GCF enzyme levels were calculated and evaluated both as total enzyme activity and enzyme concentration. The correlations between these GCF enzymes and clinical periodontal status were also analyzed.

RESULTS

With both modes of data presentation, the results regarding MPO activity were consistent. When presented either as total MPO activity or MPO concentration, the periodontally healthy group showed significantly lower MPO activity than the two patient groups (P<0.05). However, two modes of data presentation did not match when GCF ELA was concerned. When data were reported as total ELA, the healthy group exhibited lower enzyme activity (0.02 +/- 0.001 U) than EOP (0.04 +/- 0.01 U) and AP (0.06 +/- 0.02 U) groups; but when reported as concentration, the highest ELA levels were seen in the healthy group (221 +/- 31.53 nmol/min/ml), followed by AP (98.63 +/- 23.03 nmol/min/ml) and EOP (70.49 +/- 12.02 nmol/min/ml) (P<0.05). A strong-positive and significant correlation existed between GCF MPO and ELA. Correlations with clinical parameters were mostly observed with total activities.

CONCLUSIONS

The findings of the present study confirm the relationship between GCF ELA and MPO activity and periodontal disease and also support the functional relativity between the two enzymes. Furthermore, based on these findings, it can be suggested that data presentation by use of total activity seems to be more sensitive in both the reflection of the actual enzymatic profile of GCF and also the existing clinical periodontal status. For each GCF component, the validity of different modes of data presentation should be considered.

Periodontitis

The purpose of this review was to assess the scientific and clinical bases for the proposed classification of periodontitis. The clinical and histopathological signs and the etiology of periodontitis were described. Cross-sectional studies were analyzed to determine when onset of periodontitis most frequently occurs in adults. In addition, the progression rates of periodontitis have been assessed from longitudinal studies. No clinical, histopathological, or microbiological features could be identified that would characterize different disease entities of chronic periodontitis. The prevalence, extent, and severity of periodontitis were found to increase continually with higher age and there was no age when onset of disease would most likely occur. The rate of periodontitis progression varies largely between patients and there is no natural threshold for distinguishing various rates of disease progression. The incidence of periodontitis unresponsive to treatment depends on pretreatment progression rate, extent and severity of disease, tooth type, smoking, high levels of putative periodontal pathogens, a deficient immune response, and the type of therapy provided. There is no scientific basis for the classification "adult periodontitis" and "refractory adult periodontitis." Extensive clinical examinations are required for the diagnosis of "rapidly progressive adult periodontitis." It appears unrealistic that these examinations can be performed routinely in clinical practice. Therefore, the classification proposed by the Organizing Committee to define adult, rapidly progressive, and refractory periodontitis as specific disease entities was replaced with a simplified classification of periodontitis based on the scientific data available.

Analysis of gingival crevicular fluid intracytoplasmic enzyme activity in patients with adult periodontitis and rapidly progressive periodontitis. A longitudinal study model with periodontal treatment

In the present study, the activity of 3 functionally related enzymes, creatine kinase (CK), lactate dehydrogenase (LDH), and aspartate aminotransferase (AST) levels in the rest and flow gingival crevicular fluid (rGCF, fGCF) from patients with rapidly progressive periodontitis (RPP) and adult periodontitis (AP) were determined before and after periodontal treatment, including maintenance. When rGCF and fGCF mean enzyme levels were compared, rGCF was found to contain approximately twice as much enzyme levels than fGCF throughout the study. The findings of the present study revealed that both the rGCF and fGCF samples also contained higher CK, LDH, and AST levels than serum samples. Baseline clinical parameters and GCF enzyme levels presented a significant decline throughout the non-surgical and surgical treatment phases in both patient groups, with surgical treatment being more effective. Despite clinical stability, in the AP group levels of LDH and AST showed a tendency to increase in the third month, while enzyme levels still continued to decrease in the RPP group, who received additional antibiotics during the surgical phase. These findings suggest that GCF intracytoplasmic enzyme profile is related with periodontal status and successful periodontal treatment, in addition to clinical improvement, has a significant effect on this profile. Analysis of biochemical events, more specifically intracytoplasmic enzyme levels in GCF, are likely to offer a sensitive measure of periodontal pathology which may help in overcoming the existing limitations of clinical parameters. For this purpose, analysis of rGCF intracytoplasmic enzymes seems to be more beneficial.

Association of crevicular fluid elastase-like activity with histologically-confirmed attachment loss in ligature-induced periodontitis in beagle dogs

Experimental periodontitis was induced using ligatures in 6 beagle dogs over 57 days. Levels of elastase like activity in healthy sites, gingivitis sites, and in sites ligated for different time points were analyzed with respect to levels of histologically confirmed attachment loss. Attachment loss increased with increasing periods of ligation and reached a maximum of 0.15 mm at 57 days. Maximum loss of histological attachment was found to coincide with the period of maximum enzyme activity; during the first 7 days of ligature. Spearman correlation analysis of enzyme activity with attachment loss yielded a significant correlation (0.73, p=0.0396). The healthy and gingivitis sites were found to have minimal levels of enzyme activity throughout. Thus, this prospective study in beagle dogs found a relationship between histologically confirmed attachment loss and increased levels of elastase like activity indicating the probable usefulness of this parameter, either alone or in conjunction with other markers, for disclosing active periodontitis.

Investigations into the cellular contribution to host tissue proteases and inhibitors in gingival crevicular fluid

Gingival crevicular fluid (GCF) was collected from chronic periodontitis patients using plastic micropipettes and coverslip smears stained with antibodies for leukocyte markers and Toluidine Blue for mast cells. The smears consisted of 70-80% granulocytes, 10-20% monocytes/macrophages, 5% mast cells and 5% T lymphocytes; no B lymphocytes were found. Proteases and inhibitors in GCF cells were investigated by enzyme cytochemistry using 2-methoxy-4-naphthylamine-linked peptide substrates and simultaneous coupling to Fast Blue B and immunocytochemistry using biotinylated secondary antibodies and an alkaline phosphatase/new fuchsin detecting system. Elastase was detected in granulocytes, cathepsin B in macrophages, dipeptidyl peptidases II and IV in a small proportion of macrophages, dipeptidyl peptidase IV in a few T lymphocytes, tryptase in mast cells and alpha-1-proteinase inhibitor and alpha-2-macroglobulin in some macrophages. GCF was also collected on filter paper strips and eluted into buffer for biochemical enzyme assays. Lysis of cells by addition of detergent to the elution buffer increased activities to 140-240% of control values. Removal of cells by centrifugation reduced measured activities to 1-30% of original figures; this effect was less if samples were pre-treated with detergent. Proteases from inflammatory cells therefore appear to make up most of the measured enzyme activity in GCF, and this association may explain recent correlations with periodontal disease progression.