Analysis of gingival crevice fluid and risk of progression 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.

Specified species in gingival crevicular fluid predict bacterial diversity

BACKGROUND

Analysis of gingival crevicular fluid (GCF) samples may give information of unattached (planktonic) subgingival bacteria. Our study represents the first one targeting the identity of bacteria in GCF.

METHODOLOGY/PRINCIPAL FINDINGS

We determined bacterial species diversity in GCF samples of a group of periodontitis patients and delineated contributing bacterial and host-associated factors. Subgingival paper point (PP) samples from the same sites were taken for comparison. After DNA extraction, 16S rRNA genes were PCR amplified and DNA-DNA hybridization was performed using a microarray for over 300 bacterial species or groups. Altogether 133 species from 41 genera and 8 phyla were detected with 9 to 62 and 18 to 64 species in GCF and PP samples, respectively, per patient. Projection to latent structures by means of partial least squares (PLS) was applied to the multivariate data analysis. PLS regression analysis showed that species of genera including Campylobacter, Selenomonas, Porphyromonas, Catonella, Tannerella, Dialister, Peptostreptococcus, Streptococcus and Eubacterium had significant positive correlations and the number of teeth with low-grade attachment loss a significant negative correlation to species diversity in GCF samples. OPLS/O2PLS discriminant analysis revealed significant positive correlations to GCF sample group membership for species of genera Campylobacter, Leptotrichia, Prevotella, Dialister, Tannerella, Haemophilus, Fusobacterium, Eubacterium, and Actinomyces.

CONCLUSIONS/SIGNIFICANCE

Among a variety of detected species those traditionally classified as Gram-negative anaerobes growing in mature subgingival biofilms were the main predictors for species diversity in GCF samples as well as responsible for distinguishing GCF samples from PP samples. GCF bacteria may provide new prospects for studying dynamic properties of subgingival biofilms.

Relevance of gingival crevice fluid components in assessment of periodontal disease - A critical analysis

Monitoring infections which are episodic, site specific, localized or generalized, initiated by a number of microorganisms and assessed with measurement devices that have inherent shortcomings presents a difficult task. The lack of precise clinical criteria for assessment of periodontal disease has led to a search for alternative means of determining active disease sites, predicting future sites of breakdown and evaluating response to therapy. This paper highlights the potential array of biomarkers present in gingival crevice fluid (GCF) and provides an insight of which of these factors has the greatest diagnostic potential. The rationale behind using GCF as sampling source is also described. Finally it discusses the possible use of predictive chair side diagnostic tests in periodontitis.

Levels of specific immunoglobulin G to the forsythia detaching factor of Tannerella forsythia in gingival crevicular fluid are related to the periodontal status

BACKGROUND AND OBJECTIVE

Forsythia detaching factor (FDF) is a putative virulence factor of Tannerella forsythia that induces detachment of adherent cells and interleukin-8 production in human fibroblasts. The objective of the present study was to clarify the relationship between anti-FDF IgG levels in gingival crevicular fluid and the clinical status in patients with periodontitis and in healthy subjects.

MATERIAL AND METHODS

Gingival crevicular fluid and subgingival plaque samples were obtained from both the diseased and healthy sites of 37 patients with periodontitis and from 30 healthy subjects. Anti-FDF IgG levels were evaluated, and both the fdf gene and T. forsythia 16S ribosomal RNA (rRNA) were detected using the PCR.

RESULTS

Anti-FDF IgG levels (of both diseased and healthy sites) of patients with periodontitis were significantly higher than those of healthy subjects. Among the patients with periodontitis, anti-FDF IgG levels of healthy sites were significantly higher than those of diseased sites and the levels showed negative correlations with probing pocket depth and clinical attachment level. Among the patients with periodontitis, T. forsythia 16S rRNA was detected in 18 of 37 diseased sites and in 5 of 29 healthy sites, and the fdf gene was detected in 19 of 37 diseased sites and in 7 of 29 healthy sites. By contrast, no healthy subjects were positive for T. forsythia 16S rRNA or the fdf gene.

CONCLUSION

These data suggest that anti-FDF IgG levels in gingival crevicular fluid are related to the periodontal status.

Myeloid-related protein (MRP8/14) expression in gingival crevice fluid in periodontal health and disease and after treatment

BACKGROUND AND OBJECTIVE

Myeloid-related protein (MRP8/14) and its subunits are biomarkers of inflammation. The present study evaluated whether gingival crevice fluid levels of these markers discriminate periodontitis from healthy sites in patients with chronic periodontitis or diseased from healthy subjects, and whether these biomarkers detect longitudinal changes after therapy.

MATERIAL AND METHODS

Levels of MRP8/14, MRP14 and total protein were quantified in 19 periodontitis patients before non-surgical periodontal therapy, after 3 and 6 mo of treatment, and were measured once in 11 periodontally healthy subjects. In total, diseased subjects contributed 59 sites with probing depths >4 mm (PP) and 21 sites <4 mm (PH); healthy subjects contributed 91 sites (HH).

RESULTS

Overall, in diseased subjects, MRP8/14, MRP14 and total protein were not significantly different between PP and PH sites. However, at baseline, MRP8/14 and total protein had significantly higher values at sites in periodontally diseased than in healthy subjects. Clinical improvement was associated with a significant decrease of MRP8/14 and MRP14 from baseline to month 6 in PP sites. Interestingly, a similar decrease was observed in PH sites for all three markers. At 6 mo, however, levels of MRP8/14 and protein in PP and PH sites of patients were still significantly higher than in healthy subjects.

CONCLUSION

Gingival crevice fluid levels of MRP8/14 did not differentiate between clinically diseased and healthy sites in patients with chronic periodontitis. However, this marker was elevated in periodontally diseased compared with healthy subjects, and its values decreased following therapy. MRP8/14 may be used to monitor the response to treatment.

Raised chondroitin sulphate WF6 epitope levels in gingival crevicular fluid in chronic periodontitis

AIM

To determine the levels of chondroitin sulphate (CS) WF6 epitope, recognized by WF6 monoclonal antibody, in gingival crevicular fluid (GCF) from different stages of periodontal disease and healthy periodontium, and to correlate those levels with clinical parameters.

MATERIAL AND METHODS

GCF samples, collected from 389 sites, were analysed for the WF6 epitope levels by the competitive enzyme-linked immunosorbent assay.

RESULTS

The median WF6 epitope level was significantly higher in chronic periodontitis sites (n=185) than in healthy and gingivitis sites (n=204) (p<0.001), whereas the median levels did not significantly differ between healthy (n=65) and gingivitis sites (n=139). The median level in severe periodontitis sites (n=60) was significantly higher than that in moderate periodontitis sites (n=63) (p=0.019). Similarly, the median level in moderate periodontitis sites was significantly higher than that in slight periodontitis sites (n=62) (p=0.001). The WF6 epitope levels significantly correlated with probing depth (r=0.777, p=0.001) and loss of clinical attachment level (r=0.814, p=0.001).

CONCLUSION

Elevated CS WF6 epitope levels in GCF are associated with severity of periodontitis. The WF6 antibody may therefore be clinically applied to monitor disease severity and progression.

IL1B gene promoter haplotype pairs predict clinical levels of interleukin-1beta and C-reactive protein

Interleukin-1beta (IL-1beta) activates inflammatory mediator cascades and has been implicated in the pathogenesis of several diseases. Single nucleotide polymorphisms (SNPs) of the IL1B promoter have been associated with various inflammatory diseases. We recently reported that IL1B gene transcription was influenced by four promoter SNPs, and that individual SNP function in vitro was governed by haplotype context. In the present study we tested the in vivo relevance of this observation by comparing IL1B promoter haplotype-pairs with IL-1beta protein levels in 900 gingival tissue fluid samples. Three SNPs (-511, -1464, -3737) defined four IL1B promoter haplotypes that occurred in the study population and could be assigned unambiguously to each chromosome. The four haplotypes defined ten haplotype-pairs of which four pairs, representing 57% of the population, were associated with 28-52% higher IL-1beta protein levels in vivo. Two of these pairs, characterized by homozygosity for the common allele at -3737, were also associated with raised serum levels of C-reactive protein (p = 0.02). We validated these findings in stimulated peripheral blood mononuclear cells (PBMCs) from a separate population (N = 70). PBMCs with IL1B haplotype-pairs associated with higher in vivo levels of IL-1beta produced 86-287% more IL-1beta in vitro than the reference group. We believe that this is the first demonstration of a relationship between in vivo levels of an inflammatory mediator and gene promoter haplotypes on both chromosomes. These findings may apply to other inducible genes and could provide a logical framework for exploring disease risk related to genetic variability in pathogenic mediators.

Periodontal conditions in subjects following orthodontic therapy. A preliminary study

The present study evaluated the periodontal conditions in dental students after appliance removal (mean period 7.16 +/- 3.5 years) compared with an untreated control group. Twenty-five subjects in the treated group (16 females and 9 males: 23.0 +/- 2.04 years) and 29 in a control group (15 females and 14 males: 23.99 +/- 2.46 years) underwent a periodontal examination: visible plaque index (VPI), gingival bleeding index (GBI), bleeding on probing (BOP), periodontal probing depth (PPD), and clinical attachment loss (CAL) of canines, premolars, and banded first molars and unbanded second molars. Statistical analysis was performed using a Mann-Whitney test, a Student's t-test, and Tukey's analysis of variance. The level of significance was set at 5 per cent. The median percentage of positive sites for the treated and control groups for VPI (1.25 +/- 2.37 and 1.25 +/- 5.45), GBI (0.95 +/- 1.81 and 1.23 +/- 2.14), and BOP (0.83 +/- 6.45 and 0.83 +/- 3.43) did not differ between groups. Mean PPD values were 1.33 +/- 0.19 and 1.34 +/- 0.14 for the treated and 1.40 +/- 0.24 and 1.39 +/- 0.25 for the control group. No intra- or intergroup differences were observed. For the control group, the smallest PPD was at the canines followed by premolars and molars. PPD was less for premolars than molars but similar to the canines in the treated group. No differences in CAL were observed between the examined teeth in the control group. For the treated group, the canines showed lower CAL values than the first molars. The results indicate that the use of orthodontic appliances is not necessarily related to a worsening of periodontal conditions.

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.

Antimicrobial mouthrinses and the management of periodontal diseases

BACKGROUND

Periodontal diseases are complex disorders that have been associated with multiple risk factors. These disorders are triggered by the accumulation of dental plaque, and the clinical signs are caused by the resultant inflammatory and immune responses. Tissue destruction that defines periodontitis has been linked to excessive production of proinflammatory molecules including matrix metalloproteinases, interleukin-1 beta and prostaglandin E(2). Important risk factors for periodontitis can be grouped into four categories: microbial, systemic, behavioral and local. These risk factors can be considered modifiable or unmodifiable. Controlling risk factors is important in the management of chronic diseases and is a valid strategy for controlling periodontal diseases. Limiting the accumulation of dental plaque is an important part of controlling the development and progression of periodontal diseases. By adhering to a daily oral hygiene regimen that includes brushing, flossing and rinsing, patients play an essential role in disease management.

CONCLUSION

Patients play an important role in controlling the oral microbial biofilm that is essential to the initiation, development and progression of periodontal diseases. A daily oral hygiene regimen that includes the use of an antimicrobial mouthrinse can modify patients' microbial risk of developing periodontal disease.

CLINICAL IMPLICATIONS

Patients can help reduce their risk of developing periodontal disease by controlling the accumulation of plaque. This can be accomplished, in part, by adhering to a daily oral hygiene regimen that includes brushing, flossing and using an antimicrobial mouthrinse.

Enamel Matrix Derivative and Systemic Antibiotics as Adjuncts to Non-Surgical Periodontal Treatment: Biologic Response

BACKGROUND

Short-term clinical observations suggest an anti-inflammatory effect of enamel matrix derivative (EMD). The purpose of this study was to evaluate the anti-inflammatory capacity of EMD, used as an adjunct to non-surgical periodontal treatment of deep lesions in chronic periodontitis patients, by monitoring inflammatory markers in gingival crevicular fluid (GCF).

METHODS

Sixteen subjects were randomly assigned to treatment with EMD or placebo in contralateral dentition areas. Half of the subjects received 250 mg metronidazole and 375 mg amoxicillin three times a day for 7 days; the other half received a placebo. GCF samples were collected from one interproximal lesion in each of the contralateral quadrants before treatment and after 10 days and 2, 6, and 12 months. Total protein content was determined according to the Bradford method. Myeloid-related protein (MRP) 8/14 and interleukin (IL)-1beta were analyzed quantitatively by enzyme-linked immunosorbent assay (ELISA), and elastase activity was determined using a low molecular weight fluorogenic substrate.

RESULTS

No significant differences were observed between sites treated with or without EMD for any biochemical parameter. Two months after treatment, subjects treated with antibiotics exhibited less clinical signs of inflammation. Furthermore, these subjects had lower MRP 8/14 levels only at day 10 compared to those receiving the placebo. For total protein, IL-1beta, and elastase, no statistically significant differences were noted for subjects with or without antibiotic therapy at any time point.

CONCLUSIONS

Improved healing of the soft tissues has been noted clinically in non-surgically treated sites in subjects treated with antibiotics. The expression of inflammatory mediators in GCF corroborated this finding only in part. EMD did not seem to further affect the expression of inflammatory mediators.

The use of surrogate variables to reflect long-term tooth survivability

Clinical parameters used to monitor periodontal patients are usually measures of the disease process. They are considered surrogate variables because changes in their status are interpreted to have an impact on the ultimate goal of periodontal therapy, which is tooth retention. However, their ability to reflect tooth survivability has been questioned because there is a lack of long-term data to validate that stable or improved surrogates result in reduced tooth loss. Therefore, to clarify the utility of employing surrogates to reflect long-term tooth retention, a number of issues related to their use are discussed in this commentary: phraseology, benefits and shortcomings, biologic credibility, and their previous successful utilization in monitoring the effects of therapy. This commentary supports the reasonableness of using surrogates to monitor periodontal status and suggests that a combination of surrogates that represent "periodontal clinical health" should be considered a true endpoint of periodontal therapy, since this outcome provides a condition conducive to tooth retention.