Evaluation of components of gingival crevicular fluid as diagnostic tests

The role of salivary metabolomics in chronic periodontitis: bridging oral and systemic diseases

BACKGROUND

Chronic periodontitis is a condition impacting approximately 50% of the world's population. As chronic periodontitis progresses, the bacteria in the oral cavity change resulting in new microbial interactions which in turn influence metabolite production. Chronic periodontitis manifests with inflammation of the periodontal tissues, which is progressively developed due to bacterial infection and prolonged bacterial interaction with the host immune response. The bi-directional relationship between periodontitis and systemic diseases has been reported in many previous studies. Traditional diagnostic methods for chronic periodontitis and systemic diseases such as chronic kidney diseases (CKD) have limitations due to their invasiveness, requiring practised individuals for sample collection, frequent blood collection, and long waiting times for the results. More rapid methods are required to detect such systemic diseases, however, the metabolic profiles of the oral cavity first need to be determined.

AIM OF REVIEW

In this review, we explored metabolomics studies that have investigated salivary metabolic profiles associated with chronic periodontitis and systemic illnesses including CKD, oral cancer, Alzheimer's disease, Parkinsons's disease, and diabetes to highlight the most recent methodologies that have been applied in this field.

KEY SCIENTIFIC CONCEPTS OF THE REVIEW

Of the rapid, high throughput techniques for metabolite profiling, Nuclear magnetic resonance (NMR) spectroscopy was the most applied technique, followed by liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS). Furthermore, Raman spectroscopy was the most used vibrational spectroscopic technique for comparison of the saliva from periodontitis patients to healthy individuals, whilst Fourier Transform Infra-Red Spectroscopy (FT-IR) was not utilised as much in this field. A recommendation for cultivating periodontal bacteria in a synthetic medium designed to replicate the conditions and composition of saliva in the oral environment is suggested to facilitate the identification of their metabolites. This approach is instrumental in assessing the potential of these metabolites as biomarkers for systemic illnesses.

Association between raftlin and presepsin levels with periodontal healthy and disease conditions

OBJECTIVE

The aim of this study was to examine the association between Raftlin and Presepsin levels in periodontal healthy/diseases, hypothesizing a change in their levels. Also, the study aimed to determine their potential role in diagnosing and predicting the prognosis of periodontal diseases.

DESIGN

A cross-sectional study design was used, including 20 periodontally healthy individuals, 21 gingivitis patients, and 21 periodontitis patients. Clinical measurements and gingival crevicular fluid (GCF) sample collection were conducted, and the levels of Raftlin and Presepsin were analyzed. Statistical analysis was performed to evaluate the differences and correlations among the groups.

RESULTS

Raftlin and Presepsin levels displayed significant variations among groups in both total amount (mean values for Raftlin in periodontitis, gingivitis, and healthy were 33.42, 17.45, 7.70 pg/30 s, respectively; for Presepsin, values were 3.98, 3.01, 1.92 pg/30 s, respectively) (p < 0.001) and concentration levels (pg/μl) (p = 0.007 for Raftlin, p = 0.026 for Presepsin). Particularly noteworthy were the concentration distinctions observed exclusively between the periodontitis and healthy groups.

CONCLUSIONS

The present study offers preliminary insights into the presence and variations of raftlin and prepsepsin in the GCF across different periodontal conditions. While these findings hint at a potential role for these markers in periodontal disease, further research is essential to fully understand their diagnostic and prognostic capabilities.

Periostin level in gingival crevicular fluid in periodontal disease: a systematic review and meta-analysis

BACKGROUND

Periostin, a secreted adhesion molecule, is a matricellular protein secreted most in periodontal ligament and periosteum. Periostin is also needed for integrity and maturation of periodontal tissue. This meta-analysis was conducted to compare the gingival crevicular fluid (GCF) periostin levels in subjects having periodontal disease and healthy periodontium.

METHODS

In this meta-analysis, three international database including PubMed, Scopus and Web of Science were searched and 207 studies retrieved. Also, the Google Scholar was searched to find more related studies (two studies were found). To assess the risk of bias of included studies, the Newcastle-Ottawa assessment scale adapted for case-control was used. Finally, required data was extracted and included into analysis. All statistical analysis were done using Stata software.

RESULTS

Eight studies were included in this meta-analysis. Results showed that GCF periostin level is significant lower in chronic periodontitis group compare to healthy people (the standardized mean difference (SMD) = -3.15, 95% CI = -4.45, -1.85, p < 0.001). The syntheses of studies shown a significant decrease in the periostin level of chronic periodontitis patients compared to the gingivitis patients (SMD = -1.50, 95%CI = -2.52, -0.49, P = 0.003), while the mean level of periostin between the gingivitis patients and healthy group has no significant difference (SMD = -0.88, 95%CI = -2.14, 0.38, P = 0.173).

CONCLUSION

The mean concentration of GCF periostin in people with chronic periodontitis significantly decreased compared to people with gingivitis and also compared to healthy people, while no significant difference was observed between the two groups with gingivitis and healthy people. Therefore, this marker may be used as a diagnostic criterion for the disease, which requires further studies.

Gingival crevicular fluid lipocalin-2 and semaphorin3A in stage III periodontitis: Non-surgical periodontal treatment effects

BACKGROUND AND OBJECTIVE

Identification of biomarkers to assess individual risk and monitor periodontal health status is important. Research on lipocalin-2 (LCN2) and semaphorin3A (Sema3A) is lacking. This study aimed to evaluate gingival crevicular fluid (GCF) LCN2, Sema3A, and tumor necrosis factor-α (TNF-α) levels in periodontally healthy (H), gingivitis (G), and periodontitis (P) patients, and their changes following non-surgical periodontal therapy.

METHODS

Sixty systemically healthy and non-smoker participants, diagnosed as periodontally healthy, gingivitis, and stage III grade C periodontitis, were recruited (n = 20/group). Clinical periodontal parameters were recorded and GCF samples were obtained at baseline from all groups; for group P, these were repeated one and three months following non-surgical periodontal treatment. GCF LCN2, Sema3A, and TNF-α levels were evaluated with enzyme-linked immunosorbent assay.

RESULTS

GCF LCN2, Sema3A, and TNF-α total amounts were significantly higher in disease groups than group H (p < .001). Between P and G groups, only TNF-α levels were significantly different (p < .001). Non-surgical periodontal therapy resulted in significant improvement of all clinical parameters and significant decreases of GCF LCN2 and TNF-α levels, at both time points, compared with baseline (p < .001). Sema3A levels remained unchanged following treatment (p > .05). LCN2 and TNF-α levels were significantly positively correlated with clinical parameters. LCN2 (AUC [area under the curve] = 0.94) and TNF-α (AUC = 0.98) levels were similarly accurate in differentiating between periodontal disease (whether G or P) and healthy controls.

CONCLUSIONS

LCN2 and TNF-α levels in GCF are correlated with clinical parameters and could prove useful as non-invasive screening tools for periodontitis.

Periodontal Disease: The Good, The Bad, and The Unknown

Periodontal disease is classically characterized by progressive destruction of the soft and hard tissues of the periodontal complex, mediated by an interplay between dysbiotic microbial communities and aberrant immune responses within gingival and periodontal tissues. Putative periodontal pathogens are enriched as the resident oral microbiota becomes dysbiotic and inflammatory responses evoke tissue destruction, thus inducing an unremitting positive feedback loop of proteolysis, inflammation, and enrichment for periodontal pathogens. Keystone microbial pathogens and sustained gingival inflammation are critical to periodontal disease progression. However, recent studies have revealed the importance of previously unidentified microbes involved in disease progression, including various viruses, phages and bacterial species. Moreover, newly identified immunological and genetic mechanisms, as well as environmental host factors, including diet and lifestyle, have been discerned in recent years as further contributory factors in periodontitis. These factors have collectively expanded the established narrative of periodontal disease progression. In line with this, new ideologies related to maintaining periodontal health and treating existing disease have been explored, such as the application of oral probiotics, to limit and attenuate disease progression. The role of systemic host pathologies, such as autoimmune disorders and diabetes, in periodontal disease pathogenesis has been well noted. Recent studies have additionally identified the reciprocated importance of periodontal disease in potentiating systemic disease states at distal sites, such as in Alzheimer's disease, inflammatory bowel diseases, and oral cancer, further highlighting the importance of the oral cavity in systemic health. Here we review long-standing knowledge of periodontal disease progression while integrating novel research concepts that have broadened our understanding of periodontal health and disease. Further, we delve into innovative hypotheses that may evolve to address significant gaps in the foundational knowledge of periodontal disease.

WNT-5a and SOST Levels in Gingival Crevicular Fluid Depend on the Inflammatory and Osteoclastogenic Activities of Periodontal Tissues

Background and Objectives: Wnt signaling leads to stimulation of osteoblasts and it reduces osteoclastogenesis and bone resorption via the regulation of the osteprotegrin and receptor activator of nuclear factor kappa-Β ligan (RANKL). Wnt signaling pathways are regulated by their physiological antagonists such as sclerostin (SOST) as well as WNT-5a. The aim of this study was to determine the total amount of Sclerostin and WNT-5a in the gingival crevicular fluid (GCF) in sites with a continuum from a healthy to diseased periodontium. Materials and Methods: In this cross-sectional study, a total of 20 patients with generalized periodontitis, 10 subjects with gingivitis as well as 14 individuals with a healthy periodontium were recruited upon clinical and radiographic periodontal examination. In patients diagnosed with periodontitis, GCF samples were collected from periodontitis, gingivitis and healthy sites, while gingivitis patients provided samples from gingivitis and healthy sites. In healthy patients, only healthy sites were sampled. Protein total amount of SOST and WNT-5a were quantified by sandwich enzyme-linked immunosorbent assay (ELISA). Results: A total of 108 GCF samples were collected from a total of 44 individuals. When all periodontitis (n = 51), gingivitis (n = 12) and healthy (n = 45) sites were analyzed regardless of the patient diagnosis, periodontitis sites demonstrated significantly elevated WNT-5a total amounts (p = 0.03) when compared to gingivitis sites. Gingivitis sites demonstrated a trend of more total SOST (p = 0.09) when compared to periodontitis and healthy sites. Within each patient diagnostic category, sites showed similar SOST and WNT-5a total amounts (p > 0.05). Conclusions: WNT-5a levels in GCF depend on the stage of periodontitis sites. SOST trended higher in the GCF of gingivitis sites but similar in chronic periodontitis and healthy sites. WNT-5a and SOST play a crucial role in periodontal tissue remodeling and depend on the inflammatory and osteoclastogenic activities.

Impact of Smoking on Neutrophil Enzyme Levels in Gingivitis: A Case-Control Study

Background: The determination of the impact of risk factors such as smoking in periodontal disease development is of importance to better characterize the disease. However, its impact on host response remains unclear. This study aimed to evaluate the effects of tobacco smoking on GCF levels of neutrophil enzymes (myeloperoxidase (MPO), beta-glucuronidase (BGD), neutrophil elastase (NE) and periodontal parameters in healthy young adults with dental plaque biofilm-induced gingivitis. Methods: The study population consisted of 60 systemically healthy young adults (39 smokers (Sm) and 21 non-smokers (n-Sm)) diagnosed with plaque-induced gingivitis. The periodontal examination consisted of a plaque index (PI); gingival index (GI); probing depth (PD); bleeding on probing (BoP), and clinical attachment level (CAL). GCF MPO, BGD, and NE levels were determined by means of an enzyme-linked immunosorbent assay (ELISA). Results: PI, GI, and BoP were significantly increased in the Sm group (p < 0.05). PD and CAL showed no significant difference between Sm and n-Sm groups (p > 0.05). In GCF, MPO, BGD, and NE levels were significantly increased in Sm group (p < 0.05). NE levels showed a significant correlation with GI and BoP (p < 0.05 for both). Moreover, a positive correlation between BGD and NE levels (p < 0.05) was measured. Conclusions: It may be concluded that, even in young patients, tobacco consumption affects the host’s immune response related to gingival inflammation. It is, therefore, mandatory to inform young patients about the risk related to tobacco consumption for their gingival health.

Melatonin as a Topical/Systemic Formulation for the Management of Periodontitis: A Systematic Review

OBJECTIVES

To qualitatively and quantitatively review the use of melatonin as a topical/systemic formulation for the management of periodontitis.

MATERIALS AND METHODS

PubMed; Scopus; and Web of Science databases were searched using the MesH terms "melatonin" and "periodontitis". Title and abstracts were screened to eliminate irrelevant and duplicate articles. The full text data of the screened articles were assessed using the selection criteria.

RESULTS

Of 176 identified articles (PubMed-66; Scopus-56; Web of Science-52; Cross-reference-2), only 12 studies qualified to be included in the systematic review. Four studies assessed the independent effect of 1% topical melatonin formulation while 8 articles assessed the adjunctive use of systemic melatonin formulation (1-10 mg) following scaling and root planing (SRP). All studies showed an improvement in periodontal parameters such as pocket depth, clinical attachment loss, periodontal disease index, community periodontal index, gingival bleeding scores, and prognostic marker levels in saliva and serum. A meta-analysis of data from 2 studies revealed that 1-2 mg (systemic) melatonin supplementation reduced pocket depth; although the difference was not statistically significant and hence cannot be interpreted or used for conclusive evidence. Risk of Bias Assessment tool (RoBANS) and Cochrane Collaboration RoB tool elicited a high risk of bias in the included studies. GRADE (recommendation assessment, development, and evaluation) inferred a weak recommendation for the use of melatonin in periodontitis management.

CONCLUSIONS

Melatonin supplementation (topical and systemic) in periodontitis patients improved key periodontal parameters including pocket depth and clinical attachment loss.

CLINICAL RELEVANCE

Melatonin could be a potential host modulatory agent for periodontitis management; although the data from the present review should be interpreted carefully due to the associated high risk of bias.

Predictive Periodontitis: The Most Promising Salivary Biomarkers for Early Diagnosis of Periodontitis

The primary cause of tooth loss in the industrialized world is periodontitis, a bacterial anaerobic infection whose pathogenesis is characterized by composite immune response. At present, the diagnose of periodontitis is made by a complete status check of the patient’s periodontal health; full-mouth plaque score, full-mouth bleeding score, probing depth, clinical attachment level, bleeding on probing, recessions, mobility, and migration are evaluated in order to provides a clear picture of the periodontal conditions of a single patient. Chair-side diagnostic tests based on whole saliva could be routinely used by periodontists for a very early diagnosis of periodontitis, monitoring, prognosis, and management of periodontal patients by biomarker detection, whose diagnostic validity is related to sensitivity and specificity. Recent paper reviews and meta-analyses have focused on five promising host derived biomarkers as candidate for early diagnosis of periodontitis: MMP-8 (Metalloproteinase-8), MIP-1α (Macrophage inflammatory protein-1 alpha), IL-1 β (Interleukin-1 beta), IL-6 (Interleukin-6), and HB (Hemoglobin), and their combinations. Chair-side Lab-on-a-chip (LOC) technology may soon become an important part of efforts to detect such biomarkers in saliva medium to improve worldwide periodontal health in developed nations as well as in underserved communities and poor countries. Their applications in preventive and predictive medicine is now fundamental, and is aimed at the early detection of risk factors or the presence or evolution of the disease, and in personalized medicine, which aims to identify tailor-made treatments for individual patients. The aim of the present paper is to be informative about host derived periodontal biomarkers and, in particular, we intend to report information about the most important immune response derived biomarkers and Hemoglobin as candidates to be routinely utilized in order to obtain a chair-side early diagnosis of periodontal disease.

Streptococcus pneumoniae, S. mitis, and S. oralis Produce a Phosphatidylglycerol-Dependent, ltaS-Independent Glycerophosphate-Linked Glycolipid

Lipoteichoic acid (LTA) is a Gram-positive bacterial cell surface polymer that participates in host-microbe interactions. It was previously reported that the major human pathogen Streptococcus pneumoniae and the closely related oral commensals S. mitis and S. oralis produce type IV LTAs. Herein, using liquid chromatography/mass spectrometry-based lipidomic analysis, we found that in addition to type IV LTA biosynthetic precursors, S. mitis, S. oralis, and S. pneumoniae also produce glycerophosphate (Gro-P)-linked dihexosyl (DH)-diacylglycerol (DAG), which is a biosynthetic precursor of type I LTA. cdsA and pgsA mutants produce DHDAG but lack (Gro-P)-DHDAG, indicating that the Gro-P moiety is derived from phosphatidylglycerol (PG), whose biosynthesis requires these genes. S. mitis, but not S. pneumoniae or S. oralis, encodes an ortholog of the PG-dependent type I LTA synthase, ltaS. By heterologous expression analyses, we confirmed that S. mitisltaS confers poly(Gro-P) synthesis in both Escherichia coli and Staphylococcus aureus and that S. mitisltaS can rescue the growth defect of an S. aureusltaS mutant. However, we do not detect a poly(Gro-P) polymer in S. mitis using an anti-type I LTA antibody. Moreover, Gro-P-linked DHDAG is still synthesized by an S. mitisltaS mutant, demonstrating that S. mitis LtaS does not catalyze Gro-P transfer to DHDAG. Finally, an S. mitisltaS mutant has increased sensitivity to human serum, demonstrating that ltaS confers a beneficial but currently undefined function in S. mitis. Overall, our results demonstrate that S. mitis, S. pneumoniae, and S. oralis produce a Gro-P-linked glycolipid via a PG-dependent, ltaS-independent mechanism.

IMPORTANCE The cell wall is a critical structural component of bacterial cells that confers important physiological functions. For pathogens, it is a site of host-pathogen interactions. In this work, we analyze the glycolipids synthesized by the mitis group streptococcal species, S. pneumoniae, S. oralis, and S. mitis. We find that all produce the glycolipid, glycerophosphate (Gro-P)-linked dihexosyl (DH)-diacylglycerol (DAG), which is a precursor for the cell wall polymer type I lipoteichoic acid in other bacteria. We investigate whether the known enzyme for type I LTA synthesis, LtaS, plays a role in synthesizing this molecule in S. mitis. Our results indicate that a novel mechanism is responsible. Our results are significant because they identify a novel feature of S. pneumoniae, S. oralis, and S. mitis glycolipid biology.

Polyamine biomarkers as indicators of human disease

The significant increase of periodontitis, chronic kidney disease (CKD), Alzheimer's disease and cancer can be attributed to an ageing population. Each disease produces a range of biomarkers that can be indicative of disease onset and progression. Biomarkers are defined as cellular (intra/extracellular components and whole cells), biochemical (metabolites, ions and toxins) or molecular (nucleic acids, proteins and lipids) alterations which are measurable in biological media such as human tissues, cells or fluids. An interesting group of biomarkers that merit further investigation are the polyamines. Polyamines are a group of molecules consisting of cadaverine, putrescine, spermine and spermidine and have been implicated in the development of a range of systemic diseases, in part due to their production in periodontitis. Cadaverine and putrescine within the periodontal environment have demonstrated cell signalling interfering abilities, by way of leukocyte migration disruption. The polyamines spermine and spermidine in tumour cells have been shown to inhibit cellular apoptosis, effectively prolonging tumorigenesis and continuation of cancer within the host. Polyamine degradation products such as acrolein have been shown to exacerbate renal damage in CKD patients. Thus, the use of such molecules has merit to be utilized in the early indication of such diseases in patients.

Assessment of mucin and alpha-amylase levels in gingival crevicular fluid of chronic periodontitis patients

BACKGROUND

Chronic periodontitis is the most common form of periodontitis. Several immune and inflammatory factors responsible for periodontal destruction have been found in gingival crevicular fluid (GCF). The current study was conducted to determine the correlation between mucin and alpha-amylase protein values in GCF with chronic periodontitis.

METHOD

Forty-five patients with moderate-to-severe chronic periodontitis were selected. Samples of GCF were taken from a specific part of a single root tooth and placed in a closed test tube containing phosphate-buffered saline (PBS) (pH = 7). Sampling was done again after one month. Pre- and post-treatment samples were analyzed for measuring the levels of mucin and alpha-amylase proteins.

RESULTS

Paired t test results for these two variables showed that the difference between mucin and alpha-amylase levels before and after treatment is significant.

CONCLUSION

The level of both mucin and alpha-amylase in GCF in patients with chronic periodontitis was higher than that of patients who have recovered successfully; and evaluating the values of these two markers could be used to determine the activity of the periodontal disease.

The diagnosis of eating disorders through mid-infrared spectroscopy of the gingival crevicular fluid: a pilot trial

PURPOSE

Eating disorders (EDs) are characterized by a persistent disturbance of eating patterns, leading to poor psychological and physical health. EDs' symptoms are diverse, but their biochemical manifestations can be identified in biofluids, as the gingival crevicular fluid (GCF). The development of a rapid and accurate analytical diagnostic technique, able to provide a wider comprehension of established biochemical abnormalities, would greatly assist EDs' management. Mid-infrared (MIR) spectroscopy gathers all the referred features, and is considered a fingerprint technique. In this pilot trial, the GCF discrimination of patients with EDs and controls was accessed through MIR spectroscopy, further elucidating the relevant spectral differences between both groups.

METHODS

GCF was collected from 20 women with ED diagnosis and from age-matched controls. Principal component analysis and partial least squares discriminant analysis (PLSDA) were conducted on GCF MIR spectra. Different PLSDA models were considered to address the predictive capability regarding patient identification, sampling site, and presence of EDs.

RESULTS

MIR spectroscopy was capable to discriminate GCF samples, between EDs and controls, with 84.1% of correct predictions. Regression coefficient vectors' analyses revealed that major differences were related to higher protein content in EDs.

CONCLUSIONS

Whether further studies are needed to validate the attained data, GCF MIR analysis may be regarded as an innovative, fast, and low-cost technique to assist on early diagnosis and clinical follow-up of EDs' patients.

LEVEL OF EVIDENCE

Level IV, case-control trial.

Microbiota in cerebrovascular disease: A key player and future therapeutic target

Stroke is the second leading cause of death and a significant cause of disability worldwide. Recent advances in DNA sequencing, proteomics, metabolomics, and computational tools are dramatically increasing access to the identification of host-microbiota interactions in systemic diseases. In this review, we describe the accumulating evidence showing how human microbiota plays an essential role in cerebrovascular diseases. We introduce the symbiotic relationships between microbiota and the mucosal immune system, focusing on differences by anatomical sites. Microbiota directly or indirectly contributes to the pathogenesis of traditional vascular risk factors including age, obesity, diabetes mellitus, dyslipidemia, and hypertension. Moreover, recent studies proposed independent effects of the microbiome on the progression of various subtypes of stroke through direct microbial invasion, exotoxins, functional amyloids, inflammation, and microbe-derived metabolites. We propose the critical concept of gene-microbial interaction to elucidate the heterogeneity of stroke and provide possible therapeutic avenues. We suggest ways to resolve the vast inter-individual diversity of cerebrovascular disease and mechanisms for personalized prevention and treatment.

Assessment of saliva and gingival crevicular fluid soluble urokinase plasminogen activator receptor (suPAR), galectin-1, and TNF-α levels in periodontal health and disease

OBJECTIVE

The aim of the study is to evaluate saliva and gingival crevicular fluid (GCF) levels of suPAR and galectin-1 in different periodontal health status and relationship between these molecules and TNF-α to understand the roles of these molecules in periodontal inflammation process.

BACKGROUND

Soluble urokinase plasminogen activator receptor (suPAR) has been described as a biological marker of inflammation and immunological activation. Galectin-1, a member of the galectin family, is an anti-inflammatory cytokine. However, to date, levels of these two molecules in periodontal health and disease have not been well documented.

METHODS

A total of 60 individuals, 20 with chronic periodontitis (group P), 20 with gingivitis (group G), and 20 with healthy periodontium (group H) were recruited for this study. Full-mouth clinical periodontal measurements were recorded in periodontal charts. GCF and whole saliva samples were collected to determine the levels of suPAR, galectin-1, and TNF-α in study groups using enzymelinked immunosorbent assay (ELISA) method.

RESULTS

The GCF total amount of suPAR, galectin-1, and TNF-α in GCF was similar in group P and G (P > .05). The GCF total amounts of these molecules in GCF were higher in the group G and P compared to the group H (P < .05), whereas the GCF concentrations of suPAR and galectin-1 were lower in the group G and P compared to the group H (P < .05).The saliva concentration of suPAR was significantly higher in group P compared to the group G and H (P < .05). It was also higher in the group G compared to the group H but there is no significant difference between the groups (P > .05). Salivary galectin-1 levels were similar in the study groups (P > .05).

CONCLUSION

Increased levels of GCF suPAR, galectin-1, and saliva suPAR in periodontal disease suggest that these molecules may play a role in the periodontal inflammation. suPAR and galectin-1 may be considered as potential biomarkers in periodontal disease.

Macrophage activity is associated with gingival inflammation: Soluble CD163 in an experimental gingivitis study

AIM

This study aimed to investigate the association between gingival inflammation and levels of soluble CD163 (sCD163), a macrophage-specific marker associated to inflammation, in young adults participating in an experimental gingivitis study.

METHODS

Forty-two university students volunteered to participate in the study, which comprised three phases: a two-week Hygiene Phase (clinical examination and professional cleaning); a three-week Induction Phase (absence of oral hygiene); and a two-week Resolution Phase (reestablishment of oral hygiene). Clinical recordings of plaque (Modified Quigley and Hein Plaque Index) and gingival inflammation (Modified Gingival Index) were collected weekly during the Induction Phase, and after two weeks during the Resolution Phase. Levels of sCD163 from gingival crevicular fluid (GCF) were collected during Induction and Resolution Phases and measured by ELISA. Group-based-trajectory-modeling (GBTM) was used to model patterns of sCD163 throughout the Induction Phase. Mixed-effects multilevel models were used to estimate the effect of gingival inflammation on sCD163 over time.

RESULTS

Levels of sCD163 increased steadily over time, however, sCD163 showed a lagged response to gingival inflammation. GBTM analysis identified two groups for sCD163: one with a "linear" trajectory of sCD163 over the Induction Phase (n = 35), and another with a "quadratic" (n = 7) increase of sCD163 at the end of the Induction Phase. Stratified analysis by the sCD163 groups revealed that "linear" sCD163 growth was associated with both GCF volume and gingival inflammation but lagged in time, while a "quadratic" growth was associated with gingival inflammation and time.

CONCLUSIONS

Macrophage activity is associated with gingival inflammation and can be detected at early stages of gingivitis. However, while in most participants a "linear" trajectory of sCD163 over the development of gingival inflammation was observed, among few individuals an exacerbated increase of sCD163 levels in GCF was noticed particularly at the end of the Induction Phase.

Gingival crevicular fluid response to protocols of non-surgical periodontal therapy: A longitudinal evaluation

Context and Aim

Gingival crevicular fluid (GCF) volume reflects the level of periodontal inflammation. This secondary analysis aimed to evaluate the GCF volume in patients submitted to non-surgical periodontal therapies under a split-mouth design.

Materials and Methods

GCF volume of 25 participants (47.24 ± 6.47 years) with moderate-to-severe chronic periodontitis was collected at Days 0, 30, 60, 90, 120, 270, and 450. The participants were submitted to three different non-surgical therapies randomly assigned per quadrant [GI: supragingival control (Supra) as only intervention (one quadrant); GII: Supra plus scaling and root planing (SRP) on Day 0 (two quadrants); GIII: Supra on Day 0 and SRP 30 days later (one quadrant)]. During treatment (0-60 days) and maintenance (90-450 days) participants were submitted to supragingival plaque control reinforcements. GCF volumes were analyzed after logarithmic transformation (log₁₀) and linear models were used for intra- and inter-group comparisons, considering the data dependence.

Results

Baseline GCF volumes were similar between groups (GI: 0.39 ± 0.22 μl; GII: 0.42 ± 0.26 μl; GIII: 0.41 ± 0.14 μl;P > 0.05). At Day 60, GCF volumes were significantly reduced (GI: 0.20 ± 0.13 μl; GII: 0.18 ± 0.11 μl; GIII: 0.22 ± 0.13 μl; P < 0.001), without inter-groups differences. These results were maintained along maintenance period (P > 0.05). Even in sites bleeding on probing (BOP) + the means of GCF volume did not differ between groups (P > 0.05).

Conclusions

All therapies determined reductions on the GCF volume along time. Supragingival plaque control modulated the subgingival area during the study, reinforcing the importance of this control over the subgingival inflammatory response.

Active matrix metalloproteinase-8 and periodontal bacteria-interlink between periodontitis and inflammatory bowel disease?

BACKGROUND

The aim of this study was the investigation of concentration and prevalence of selected periodontal pathogenic bacteria and concentration of active matrix metalloproteinase-8 (aMMP-8) within a group of patients with inflammatory bowel diseases (IBD) and to compare the results with a group of healthy control subjects (HC).

METHODS

Fifty-nine IBD patients with Crohn`s disease (CD, n = 30) or ulcerative colitis (UC, n = 29) and 59 HC were included in this cross-sectional study. Based on periodontal probing depth (PD) and clinical attachment level (CAL), periodontitis was classified as healthy/mild, moderate, or severe. aMMP-8 was analyzed from gingival crevicular fluid using enzyme linked immunosorbent assay. Eleven selected periodontal pathogenic bacteria were analyzed in subgingival plaque samples using polymerase chain reaction.

RESULTS

IBD patients showed higher CAL (P < 0.01), more severe periodontitis (P = 0.04), gingival bleeding (P < 0.01) and aMMP-8 concentration (P < 0.01) than HC. Only in CD, increasing severity of periodontitis was associated with an increase in aMMP-8 concentration (P = 0.02). The prevalences of Eubacterium nodatum and Eikenella corrodens were significantly lower in IBD compared to HC (P = 0.01). Additionally, the prevalence of Eikenella corrodens was significantly higher in CD compared to the UC group (P = 0.04). Further statistically significant differences in selected bacteria between IBD and HC or CD and UC groups could not be found (P > 0.05).

CONCLUSIONS

The results reveal changes in host immune response of IBD patients in terms of aMMP-8. Only in CD increasing aMMP-8 was associated with severity of periodontal disease. The role of periodontal pathogenic bacteria in the interrelationship between IBD and periodontitis remains unclear.

Relationship between Streptococcus mutans expressing Cnm in the oral cavity and non-alcoholic steatohepatitis: a pilot study

Background

Non-alcoholic steatohepatitis (NASH) is a severe state of non-alcoholic fatty liver disease (NAFLD), which is pathologically characterised by steatosis, hepatocyte ballooning, and lobular inflammation. Host–microbial interaction has gained attention as one of the risk factors for NASH. Recently, cnm-gene positive Streptococcus mutans expressing cell surface collagen-binding protein, Cnm (cnm-positive S. mutans), was shown to aggravate NASH in model mice. Here, we assessed the detection rate of cnm-positive S. mutans in oral samples from patients with NASH among NAFLD.

Methods

This single hospital cohort study included 41 patients with NAFLD. NASH was diagnosed histologically or by clinical score. The prevalence of cnm-positive S. mutans, oral hygiene and blood tests, including liver enzymes, adipocytokines and inflammatory and fibrosis markers, were assessed in biopsy-proven or clinically suspected NASH among NAFLD.

Results

Prevalence of cnm-positive S. mutans was significantly higher in patients with NASH than patients without NASH (OR 3.8; 95% CI 1.02 to 15.5). The cnm-positive S. mutans was related to decreased numbers of naturally remaining teeth and increased type IV collagen 7S level (median (IQR) 10.0 (5.0–17.5) vs 20.0 (5.0–25.0), p=0.06; 5.1 (4.0–7.9) vs 4.4 (3.7–5.3), p=0.13, respectively).

Conclusions

Prevalence of cnm-positive S. mutans in the oral cavity could be related to fibrosis of NASH among NAFLD.

Cytokines in gingivocrevicular fluid of rheumatoid arthritis patients: A review of the literature

OBJECTIVE

Rheumatoid arthritis (RA) and periodontitis share several pathological features including bone and soft tissue destruction and high levels of circulating inflammatory proteins. Studies related to cytokines in the periodontal inflammatory exudate (gingivocrevicular fluid, GCF) of RA patients might provide insight into the association between periodontitis and RA. The aim of our study was to review the literature on cytokines in GCF of RA patients including the effect of anti-rheumatic treatment with biological disease-modifying anti-rheumatic drugs (DMARDs) and periodontal treatment on these cytokines.

MATERIALS AND METHODS

MedLine/PubMed searches with different combinations of keywords "rheumatoid arthritis or RA" and "crevicular fluid or GCF" until June 2019 revealed 64 articles. Ten cross-sectional observational studies and nine treatment studies fulfilled the inclusion criteria.

RESULTS

Rheumatoid arthritis patients have increased circulating and GCF levels of pro-inflammatory cytokines and proteins, despite anti-rheumatic treatment with biological DMARDs. Presence of periodontitis was accompanied by higher cytokine and protein levels. Treatment of periodontitis resulted in a decrease of these levels.

CONCLUSION

Analysis of GCF of RA patients reveals that the relationship between periodontitis and RA is bidirectional, probably caused by a non-specific inflammatory burden. Data for a specific relationship are barely present in GCF.

Aliskiren Attenuates the Inflammatory Response and Wound Healing Process in Diabetic Mice With Periodontal Disease

The aim of this study was to characterize the role of local RAS (renin–angiotensin system) in the inflammatory response of normal (N) and diabetic (D) mice with periodontal disease (PD). Diabetes Mellitus (DM) was induced by peritoneal injection of streptozotocin in Balb/c mice. PD was induced by ligature around the first molar in both N and D, irrespective of whether they were treated with aliskiren (50 mg/kg, Alisk). Mandibles were harvested for histomorphometric analyses, and gingival tissue (GT) was collected to evaluate gene expression and extracellular matrix components (ECM). Immunohistochemical (IHC) analyses were used to localize RAS in GT. The production of C-reactive protein (CRP), IL-1β, CXCL2, and CCL8 was evaluated by enzyme-linked immunosorbent assay (ELISA). Renin was found to exacerbate the inflammation and periodontal bone loss at 14 days after PD, and Alisk inhibited this process in GT of N and D. PD increased CRP, CXCL2, CCL8, and IL-1β production in both animals. Alisk could inhibit CRP, CXCL2, and CCL8 primarily in D animals. However, only CCL8 was decreased in N animals after Alisk pretreatment. PD enhanced expression and production of AGT, ACE, AT1R, and AT2R in both N and D. AT1R expression was higher in D with PD, and AT2R expression was higher in N with PD. ACE2 and receptor Mas (MasR) expression and production was elevated in the control group of both animals. PD inhibited ACE2 in N but not in D. MasR expression was unaffected in both N and D with PD. Alisk reduced expression and production of all RAS components in GT of both animals, except for ACE2 in N. RAS staining was observed in all layers of epithelium, basal cell layer, and lamina propria and was higher in N with PD. Col1a1, Col1a2, Col3a1, and fibronectin (Fn1) were increased in both animals with PD. Alisk inhibited Col1a1 and Fn in both animals, Col1a2 was decreased only in D, while levels of Col3a1 remained unchanged in all animal groups. In conclusion, these data demonstrated the presence and functional role of local RAS in GT, exacerbating the inflammatory response, periodontal bone loss, and wound healing processes in both N and D animal groups. In addition, Alisk was able to significantly reduce gingival inflammation, excessive wound healing processes, and periodontal bone loss.

Adhesion and invasion of gingival epithelial cells by Porphyromonas gulae

Porphyromonas gulae, an animal periodontal pathogen, possess fimbriae classified into three genotypes (A-C) based on the diversity of fimA genes encoding FimA. Accumulating evidence suggests that P. gulae strains with type C fimbriae are more virulent as compared to those with other types. The ability of these organisms to adhere to and invade gingival epithelial cells has yet to be examined. P. gulae showed the greatest levels of adhesion and invasion at a multiplicity of infection of 100 for 90 min. P. gulae type C and some type B strains invaded gingival epithelial cells at significantly greater levels than the other strains, at the same level of efficiency as P. gingivalis with type II fimbriae. Adhesion and invasion of gingival epithelial cells by P. gulae were inhibited by cytochalasin D and sodium azide, indicating the requirements of actin polymerization and energy metabolism for those activities. Invasion within gingival epithelial cells was blocked by staurosporine, whereas those inhibitors showed little effects on adhesion, while nocodazole and cycloheximide had negligible effects on either adhesion or invasion. P. gulae proteases were found to be essential for adhesion and invasion of gingival epithelial cells, while its DNA and RNA, and protein synthesis were unnecessary for those activities. Additionally, α5β1 integrin antibodies significantly inhibited adhesion and invasion by P. gulae. This is the first report to characterize P. gulae adhesion and invasion of human gingival epithelial cells.

Gingival Crevicular Fluid: An Overview

Gingival crevicular fluid is an inflammatory exudate derived from the periodontal tissues. It is composed of serum and locally generated materials such as tissue breakdown products, inflammatory mediators, and antibodies directed against dental plaque bacteria. It plays a special part in maintaining the structure of junctional epithelium and the antimicrobial defense of periodontium. Some of the suspected periodontal pathogens such as Porphyromonas gingivalis and Treponema denticola produce broad-spectrum neutral proteinases as part of their virulence arsenal. These proteinases may be detected in plaque and gingival crevicular fluid samples of patients with periodontitis. The potential diagnostic importance of gingival fluid was recognized more than six decades ago. The fluid component of gingival crevicular fluid is derived primarily from microvascular (postcapillary venule) leakage. There are number of distinct advantages and challenges of using gingival crevicular fluid as a diagnostic test for periodontal disease.

Evaluation of chemokine CXCL10 in human gingival crevicular fluid, saliva, and serum as periodontitis biomarker

Purpose

The aim of this study was to evaluate CXCL10 as a biomarker for periodontitis by determining the CXCL10 levels in saliva, serum, and gingival crevicular fluid (GCF) samples from periodontally healthy control subjects and adult subjects with chronic periodontitis.

Patients and methods

Adult patients seeking dental treatment at Umm Al-Qura University dental clinic underwent a complete periodontal examination, and saliva, serum, and GCF samples were collected. Subjects were classified as chronic periodontitis patients (n=31) if they have a periodontal probing depth (PD) of ≥4 mm and/or clinical attachment level (CAL) of ≥3 mm in >30% of the teeth. The control group (n=25) had PD ≤3 mm and/or CAL ≤2 mm. ELISA was performed to determine the concentration of CXCL10 in saliva, serum, and GCF samples. Student’s t-test was carried out to evaluate the significant difference between different groups. Spearman’s correlation test was used to analyze the relationship between the levels of CXCL10 and the clinical periodontal parameters. P-value of ≤0.05 was considered significant.

Results

Significantly higher concentrations of CXCL10 were found in saliva and serum in chronic periodontitis patients as compared with the controls (272±60.4 pg/mL and 72±13.4 pg/mL vs 130±22.2 pg/mL and 44.08±4.5 pg/mL, P≤0.05). The CXCL10 levels in GCF were higher in the periodontitis group as compared with the control group (66.36±32.0 pg/mL and 44.56±17.5 pg/mL, respectively); the difference did not reach statistical significance (P≥0.05). Moreover, serum CXCL10 level was significantly higher in periodontitis patients with moderate to severe bone loss as compared with those with mild bone loss (71.05±4.7 pg/mL vs 54.8±7.7 pg/mL, P≤0.05). The serum CXCL10 levels were found to be related to CAL measurements (r=0.3, P=0.026), while the saliva CXCL10 levels were related to PD measurements (r=0.8, P=0.0007).

Conclusion

CXCL10 is significantly increased in periodontitis subjects as compared with controls and could be used as a marker for periodontal disease.

Comparative Evaluation of Cytokines in Gingival Crevicular Fluid and Saliva of Patients with Aggressive Periodontitis

Objectives

This study aims to evaluate and compare cytokines in gingival crevicular fluid (GCF) and saliva of patients with aggressive periodontitis (AP) before and after treatment.

Methods

Forty AP patients and 40 healthy volunteers were enrolled in this study. Clinical parameters included probing depth and sulcus bleeding index. GCF and saliva were collected from both groups. The levels of IL-1β, IL-2, IL-4, IL-6, IFN-γ and TNF-α were measured using ELISA.

Results

The probing depth in AP patients was significantly deeper before treatment than after treatment. The concentrations of cytokines in GCF and saliva were significantly higher in AP patients than in the control group and decreased after periodontal treatment. Positive relationships were found between cytokine levels in GCF and clinical parameters. The reliability of cytokines in GCF and saliva was assessed by Cronbach's alpha analysis, which could be considered satisfactory.

Conclusion

Cytokine levels in GCF and saliva correlated well with clinical parameters and AP. Measurements of cytokines in saliva may be regarded as a noninvasive and quick method for monitoring periodontal disease activity.

A systematic review of biomarkers of gingival crevicular fluid: Their predictive role in diagnosis of periodontal disease status

The objective of the study was to conduct a systematic review of the literature so as to evaluate and summarize the diagnostic and prognostic potential of GCF. Included studies were systematically analyzed based on PRISMA (Preferred Reporting Items For Systematic Reviews and Meta Analyses) and studies were identified based on the-PICO (Glossary of evidence based terms 2007): 1)Patients with chronic periodontitis.2)Intervention- NSPT (Non-SurgicalPeriodontal therapy); NSPT + Chemotherapeutics.3)Comparison between treated v/s non treated sites.4)Outcomes measured: Analysis of variation in constituents of GCF. Electronic database search of Pubmed, Medline, Google Scholar and Scopus was performed using (MeSH) terms- Gingival Crevicular fluid and Cytokines, MMP's, NE, PGE-2, A2M, B2M, ALP, AST, Osteocalcin and Calprotectin. Articles published between year 2000-2016 were reviewed and were included based on inclusion and exclusion criteria. Based on this systematic review of literature, it can be concluded that analysis of constituents of GCF can be used as an effective and efficient diagnostic tool of periodontal diseases. These biomarkers in turn with their prognostic significance could act as a valuable tool in the combat of periodontal disease.

Tissue-Specific Immunity at the Oral Mucosal Barrier

The oral mucosal barrier is constantly exposed to a plethora of triggers requiring immune control, including a diverse commensal microbiome, ongoing damage from mastication, and dietary and airborne antigens. However, how these tissue-specific cues participate in the training of immune responsiveness at this site is minimally understood. Moreover, the mechanisms mediating homeostatic immunity at this interface are not yet fully defined. Here we present basic aspects of the oral mucosal barrier and discuss local cues that may modulate and train local immune responsiveness. We particularly focus on the immune cell network mediating immune surveillance at a specific oral barrier, the gingiva - a constantly stimulated and dynamic environment where homeostasis is often disrupted, resulting in the common inflammatory disease periodontitis.

MMP-8 and TIMP-1 are associated to periodontal inflammation in patients with rheumatoid arthritis under methotrexate immunosuppression - First results of a cross-sectional study

BACKGROUND

Aim of this cross-sectional study was the investigation of associations between different rheumatoid arthritis (RA)-related blood parameters and periodontal condition as well as selected periodontal pathogenic bacteria in RA patients under methotrexate (MTX) immunosuppression.

METHODS

Periodontal probing depth (PPD), bleeding on probing (BOP) and clinical attachment loss (CAL) were assessed. Periodontal condition was classified into: no/mild and moderate or severe periodontitis (P). Prevalence of selected periodontal pathogenic bacteria and concentration of matrix metalloproteinase 8 (MMP-8) was assessed from the gingival crevicular fluid (GCF) using PCR and ELISA, respectively. Blood samples were analyzed for the concentration of selected rheumatoid parameters.

STATISTICAL ANALYSIS

t-test, Mann-Whitney-U-Test, exact Fisher tests or chi square test (p < 0.05).

RESULTS

Fifty-six patients (mean age 55.07 years, 34 P, 22 no P) were included. While prevalence of periodontal pathogenic bacteria was higher in P patients, no substantial association of bacteria with blood parameters was found. In periodontal diseased participants, MMP-8 concentration in GCF (6.22 ± 7.01 vs. 15.99 ± 13.49; p < 0.01) and blood (2.60 ± 3.57 vs. 5.52 ± 5.92; p < 0.01) was increased, while no correlation between GCF and blood was found (Spearman's rho: 0.175; p = 0.23). Furthermore, higher blood concentrations of MMP-8 and tissue inhibitor of MMP (TIMP-1) were detected in patients with increased periodontal inflammation (BOP positive, p < 0.01).

CONCLUSION

Periodontal inflammation appears associated to MMP-8 and TIMP-1 in blood. Thereby, clinical interaction between periodontal conditions, periodontal pathogenic bacteria and RA-related cytokines remain unclear.

Effect of Different Crown Materials on the InterLeukin-One Beta Content of Gingival Crevicular Fluid in Endodontically Treated Molars: An Original Research

INTRODUCTION

Crown materials used in fixed prosthodontics come into close and prolonged contact with the gingiva.

OBJECTIVE

The purpose of this study was to evaluate the effect of different crown materials on the interleukin-one beta (IL-1β) content of the gingival crevicular fluid and to study which crown material causes the highest inflammation on the marginal gingiva on a biochemical basis.

MATERIALS AND METHODS

Twenty patients with single endodontically treated tooth were examined. Contralateral teeth were taken as controls. The crown materials in contact with the marginal gingiva were divided into three groups: Group 1- metal, Group2- ceramic, Group 3-zirconia. The collected data were analyzed with International Bibliography of the Social Sciences (IBSS). Statistical Package for the Social Sciences (SPSS) Statistics software 23.0 (IBM Corp, Armonk, New York). All assay procedures were carried out and the results of the collected samples were calculated using the ELISA-AIDTM technique.

RESULTS

Multiple comparisons using one-way analysis of variance (ANOVA) between the materials on day zero, 45th and 90th day was highly significant with p=0.0005. Pairwise comparison using Tukey's honest significant difference (HSD) posthoc test was also highly statistically significant with p= 0.0005 except for ceramic & zirconia which were significant at p=0.04 on the 90th day. Multiple comparison using repeated measure of ANOVA with Bonferroni correction between day zero, 45th and 90th day was found to be statistically significant only for zirconia (p=0.002).

CONCLUSION

This study was conducted to evaluate the effect of different crown materials on the amount of marginal gingival inflammation by measuring the IL-1β content in gingival crevicular fluid (GCF). At the end of the three-month analysis, it was seen that the zirconia crowns exhibited the least marginal gingival inflammation.

The Effect of Platform Switching on Periimplant Crevicular Fluid Content During Early Wound Healing

PURPOSE

The objective of this study was to investigate the soft tissue response and periimplant crevicular fluid (PICF) content around platform-switched (PS) and platform-matched (PM) implants during early healing.

MATERIALS AND METHODS

Nonsmokers treatment planned to receive a single implant in 2 quadrants were recruited. Two-stage implant placement protocol with 1 PM and 1 PS implant was implemented. Periimplant probing depths (PDs), modified sulcus bleeding index, and plaque indices were recorded, and PICF was collected at 1, 2, 4, and 6 weeks after abutment connection.

RESULTS

PD readings were higher at week 1 than at week 6 for both groups (P = 0.0005). PD was statistically deeper in PM than in PS at week 1 (P = 0.03). There was a time-dependent decrease in total PICF volume for both groups. This decrease was statistically significant for PS (P = 0.0005), with no differences between the 2 groups at any time (P > 0.05). The decrease observed in both PM and PS for PICF interleukin 6 and macrophage inflammatory protein-1β, and in PS for tumor necrosis factor-α (TNF-α) was statistically significant (P ≤ 0.03). TNF-α was statistically higher in PS than in PM at week 1 (P = 0.005).

CONCLUSION

Within the limits of this study, it seems that periimplant soft tissue response around PM and PS implants is mostly similar during the early healing period.

Salivary Diagnostics in Pediatrics: Applicability, Translatability, and Limitations

In the last decade, technological advances, combined with an improved appreciation of the ability of saliva to inform caregivers about both oral health and systemic disease, have led to the emergence of salivary diagnostic platforms. However, the majority of these assays have targeted diseases that more commonly affect the adult population, largely neglecting infants and children who arguably could benefit the most from non-invasive assessment tools for health monitoring. Gaining access into development, infection, and disease through comprehensive "omic" analyses of saliva could significantly improve care and enhance health access. In this review, we will highlight novel applications of salivary diagnostics in pediatrics across the "omic" spectrum, including at the genomic, transcriptomic, proteomic, microbiomic, and metabolomic level. The challenges to implementing salivary platforms into care, including the effects of age, diet, and developmental stage on salivary components, will be reviewed. Ultimately, large-scale, multicenter trials must be performed to establish normative biomarker values across the age spectrum to accurately discriminate between health and disease. Only then can salivary diagnostics truly translate into pediatric care.

Human Gingival Crevicular Fluids (GCF) Proteomics: An Overview

Like other fluids of the human body, a gingival crevicular fluid (GCF) contains proteins, a diverse population of cells, desquamated epithelial cells, and bacteria from adjacent plaque. Proteomic tools have revolutionized the characterization of proteins and peptides and the detection of early disease changes in the human body. Gingival crevicular fluids (GCFs) are a very specific oral cavity fluid that represents periodontal health. Due to their non-invasive sampling, they have attracted proteome research and are used as diagnostic fluids for periodontal diseases and drug analysis. The aim of this review is to explore the proteomic science of gingival crevicular fluids (GCFs), their physiology, and their role in disease detection.

Advances of Proteomic Sciences in Dentistry

Applications of proteomics tools revolutionized various biomedical disciplines such as genetics, molecular biology, medicine, and dentistry. The aim of this review is to highlight the major milestones in proteomics in dentistry during the last fifteen years. Human oral cavity contains hard and soft tissues and various biofluids including saliva and crevicular fluid. Proteomics has brought revolution in dentistry by helping in the early diagnosis of various diseases identified by the detection of numerous biomarkers present in the oral fluids. This paper covers the role of proteomics tools for the analysis of oral tissues. In addition, dental materials proteomics and their future directions are discussed.

Alpha-2-Macroglobulin Levels in Gingival Crevicular Fluid Pre- and Post-scaling and Root Planing with Adjunctive Tetracycline Fibers in Chronic Periodontitis: A Randomized Controlled Trial

BACKGROUND

This split-mouth clinical study aimed to investigate levels of alpha-2-macroglobulin (a2M) in gingival crevicular fluid (GCF) of chronic periodontitis patients pre- and post-scaling and root planing (SRP) with or without adjunctive use of tetracycline fibers.

MATERIALS AND METHODS

In 30 patients of chronic periodontitis, samples of GCF were collected from the gingival sulcus before SRP. Recording of clinical parameters was conducted. This was followed by local drug delivery (LDD) of tetracycline fibers in test sites. In control sites, no LDD was done. Second samples of GCF were taken 90 days after treatment. Samples of crevicular fluid were analyzed to determine the levels of a2m.

RESULTS

A gain of clinical attachment (CAL) of 3.30 mm for SRP and LDD and for SRP alone was 1.62 mm (p < 0.001). The pocket probing depth was significantly decreased by 2.43 mm for SRP and LDD and for SRP alone was 1.61 mm (p < 0.001) after 90 days. Alpha-2-macroglobulin was significantly reduced in GCF by SRP and SRP and LDD after 90 days (p < 0.001).

CONCLUSION

Clinical and biochemical variables showed a more favorable outcome when SRP was combined with LDD of tetracycline fibers in management of patients suffering from chronic periodontitis.

A cross-sectional assessment of biomarker levels around implants versus natural teeth in periodontal maintenance patients

BACKGROUND

Recent studies point to the clinical utility of using peri-implant sulcular fluid (PISF) as a valuable diagnostic aid for monitoring peri-implant tissue health. The objectives of this study are to determine the levels of key biomarkers in PISF in periodontal maintenance participants and compare them with their corresponding levels in gingival crevicular fluid (GCF) obtained from the same participants.

METHODS

PISF and GCF were collected from an implant and a contralateral natural tooth after the clinical examination of 73 participants. The levels of interleukin (IL)-1α, IL-1β, IL-6, IL-8, IL-10, IL-12, IL-17A, tumor necrosis factor (TNF)-α, C-reactive protein, osteoprotegerin, leptin, and adiponectin were determined using multiplex proteomic immunoassays. The correlation of biomarker concentrations between GCF versus PISF, within GCF or PISF, and with several covariates (age, brushing frequency, days since professional cleaning, probing depth [PD], and plaque index) were also determined.

RESULTS

Significantly higher levels of IL-17A (P = 0.02) and TNF-α (P = 0.03) were noted in PISF when compared with their levels in GCF. Significant positive correlations were noted between the concentrations of cytokines in PISF versus their levels in GCF. Among the covariates, a significant positive correlation was noted between mean PDs around implants and levels of IL-1β (P <0.05) and IL-8 (P <0.05) in PISF.

CONCLUSION

The results of this study point to the differential expression of specific biomarkers in GCF versus their levels in PISF in periodontal maintenance patients, which is critical information before establishing PISF as a diagnostic fluid to monitor peri-implant health.

Periodontal proteomics: wonders never cease!

Proteins are vital parts of living organisms, as they are integral components of the physiological metabolic pathways of cells. Periodontal tissues comprise multicompartmental groups of interacting cells and matrices that provide continuous support, attachment, proprioception, and physical protection for the teeth. The proteome map, that is, complete catalogue of the matrix and cellular proteins expressed in alveolar bone, cementum, periodontal ligament, and gingiva, is to be explored for more in-depth understanding of periodontium. The ongoing research to understand the signalling pathways that allow cells to divide, differentiate, and die in controlled manner has brought us to the era of proteomics. Proteomics is defined as the study of all proteins including their relative abundance, distribution, posttranslational modifications, functions, and interactions with other macromolecules, in a given cell or organism within a given environment and at a specific stage in the cell cycle. Its application to periodontal science can be used to monitor health status, disease onset, treatment response, and outcome. Proteomics can offer answers to critical, unresolved questions such as the biological basis for the heterogeneity in gingival, alveolar bone, and cemental cell populations.

Salivary pH: A diagnostic biomarker

OBJECTIVES

Saliva contains a variety of host defense factors. It influences calculus formation and periodontal disease. Different studies have been done to find exact correlation of salivary biomarkers with periodontal disease. With a multitude of biomarkers and complexities in their determination, the salivary pH may be tried to be used as a quick chairside test. The aim of this study was to analyze the pH of saliva and determine its relevance to the severity of periodontal disease.

STUDY DESIGN

The study population consisted of 300 patients. They were divided into three groups of 100 patients each: Group A had clinically healthy gingiva, Group B who had generalized chronic gingivitis and Group C who had generalized chronic periodontitis. The randomized unstimulated saliva from each patient was collected and pH was tested. Data was analyzed statistically using analysis of variance technique.

RESULTS

The salivary pH was more alkaline for patients with generalized chronic gingivitis as compared with the control group (P = 0.001) whereas patients with generalized chronic periodontitis had more acidic pH as compared with the control group (P = 0.001).

CONCLUSION

These results indicate a significant change in the pH depending on the severity of the periodontal condition. The salivary pH shows significant changes and thus relevance to the severity of periodontal disease. Salivary pH may thus be used as a quick chairside diagnostic biomarker.

Predictive, preventive, personalised and participatory periodontology: 'the 5Ps age' has already started

An impressive progress in dentistry has been recorded in the last decades. In order to reconsider guidelines in dentistry, it is required to introduce new concepts of personalised patient treatments: the wave of predictive, preventive and personalised medicine is rapidly incoming in dentistry. Worldwide dentists have to make a big cultural effort in changing the actual 'reactive' therapeutic point of view, belonging to the last century, into a futuristic 'predictive' one. The first cause of tooth loss in industrialised world is periodontitis, a Gram-negative anaerobic infection whose pathogenesis is genetically determined and characterised by complex immune reactions. Chairside diagnostic tests based on saliva, gingival crevicular fluid and cell sampling are going to be routinely used by periodontists for a new approach to the diagnosis, monitoring, prognosis and management of periodontal patients. The futuristic '5Ps' (predictive, preventive, personalised and participatory periodontology) focuses on early integrated diagnosis (genetic, microbiology, host-derived biomarker detection) and on the active role of the patient in which networked patients will shift from being mere passengers to responsible drivers of their health. In this paper, we intend to propose five diagnostic levels (high-tech diagnostic tools, genetic susceptibility, bacterial infection, host response factors and tissue breakdown-derived products) to be evaluated with the intention to obtain a clear picture of the vulnerability of a single individual to periodontitis in order to organise patient stratification in different categories of risk. Lab-on-a-chip (LOC) technology may soon become an important part of efforts to improve worldwide periodontal health in developed nations as well as in the underserved communities, resource-poor areas and poor countries. The use of LOC devices for periodontal inspection will allow patients to be screened for periodontal diseases in settings other than the periodontist practice, such as at general practitioners, general dentists or dental hygienists. Personalised therapy tailored with respect to the particular medical reality of the specific stratified patient will be the ultimate target to be realised by the 5Ps approach. A long distance has to be covered to reach the above targets, but the pathway has already been clearly outlined.

Gingival crevicular fluid a marker of the periodontal disease activity

Gingival crevicular fluid (GCF) is an inflammatory exudate that can be collected at the gingival margin or within the gingival crevice. The biochemical analysis of the fluid offers a non invasive means of assessing the host response in periodontal disease. Active phase of periodontal disease process can be measured or assessed by the constituents of gingival fluid. Bacterial enzymes, bacterial degradation products, connective tissue degradation products, host mediated enzymes, inflammatory mediators, extracellular matrix proteins either together or individually can be detected in higher levels in gingival crevicular fluid during active phase of periodontitis.

Cytokines expression in saliva and peri-implant crevicular fluid of patients with peri-implant disease

OBJECTIVE

This study aimed to measure the levels of GM-CSF, IL-1β, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12, IFN-γ and TNF-α in peri-implant crevicular fluid (PICF) and saliva from patients with peri-implant disease.

METHODS

Twenty two total edentulous patients were divided into two groups: Mucositis (MU) patients with bone loss around the implants until the first thread and pocket depth ≤3 mm, and Peri-implantitis (PI) patients with at least one implant with bone loss around two or more threads and pocket depth ≥4 mm. The clinical parameters evaluated were probing pocket depth, bleeding on probing, and percentage of plaque. PICF samples were collected from MU sites, and from shallow (SPI) and deep (DPI) sites in PI. Unstimulated whole and parotid duct saliva was collected from all patients. The cytokines were measured by a multiplexed immunoassay.

RESULTS

PI patients had a higher percentage of plaque compared with MU (P = 0.02). MU sites had lower pocket depth compared to SPI (P = 0.001) and to DPI (P ≤ 0.001). In PICF, the levels of IL-1β were significantly higher in SPI sites compared to MU (P = 0.03). In the saliva from parotid, IL-8 and IL-12 were significantly higher in patients with PI (P = 0.04).

CONCLUSION

Elevated levels of IL-1β in PICF seem to be a characteristic trait of patients with peri-implantitis. The parotid duct saliva showed a significant increase in expression of IL-8, which might be related to a systemic response.