Smoking affects diagnostic salivary periodontal disease biomarker levels in adolescents

Diagnostic performance of a point-of-care test device for periodontitis using human saliva: a single-center, single-blinded, confirmatory study

OBJECTIVE

Recently, matrix metalloproteinase-8 (MMP-8) has been used to diagnose periodontal disease in a point-of-care (POC) test in order to save time and cost relative to the traditional diagnostic workflow. This study aimed to investigate the diagnostic performance of INCLIX TRF MMP-8, a POC testing device for periodontitis using the area under the receiver operating characteristic curve, sensitivity, specificity, and predictive values.

MATERIALS AND METHODS

Full-mouth periodontal examination and radiographic analysis were used for evaluating periodontal condition based on the 2018 classification of periodontal disease. A dichotomous diagnosis of clinical periodontal condition was performed using the POC device. The relationships among periodontal condition and the concentration of MMP-8, tooth loss (TL), gingival index (GI), plaque index (PI), and alveolar bone loss (ABL) were assessed by the Spearman rank correlations (rs).

RESULTS

In all, 108 cases of non-periodontitis (NP) and 191 cases of periodontitis (P), including 38 cases of periodontitis stage I, 42 cases of periodontitis stage II, 99 cases of periodontitis stage III, and 11 cases of periodontitis stage IV, were enrolled in this study. Diagnostic accuracy in assessing periodontal condition with the POC device improved when it was used with participants aged ≥ 40 years. There were weak positive correlations between periodontal condition and MMP-8 and between periodontal condition and GI (rs2 = 0.1124 and rs2 = 0.0906, respectively), whereas a strong positive correlation between periodontal condition and alveolar bone loss (rs2 = 0.6877) was observed.

CONCLUSION

The POC device investigated in this study is a potential tool to distinguish between NP and P in individuals ≥ 40 years of age.

Salivary E-cadherin as a biomarker for diagnosis and predicting grade of periodontitis

OBJECTIVES

To determine the abilities of salivary E-cadherin to differentiate between periodontal health and periodontitis and to discriminate grades of periodontitis.

BACKGROUND

E-cadherin is the main protein responsible for maintaining the integrity of epithelial-barrier function. Disintegration of this protein is one of the events associated with the destructive forms of periodontal disease leading to increase concentration of E-cadherin in the oral biofluids.

MATERIALS AND METHODS

A total of 63 patients with periodontitis (case) and 35 periodontally healthy subjects (control) were included. For each patient, periodontal parameters including bleeding on probing (BOP), probing pocket depth (PPD), and clinical attachment level (CAL) were recorded. Concentration of salivary E-cadherin was determined by ELISA. Receiver operating characteristic (ROC) curve and area under the curve (AUC) were used to determine the diagnostic potentials of E-cadherin.

RESULTS

Level of salivary E-cadherin was significantly higher in periodontitis cases than controls. The ROC analysis showed that salivary E-cadherin exhibits excellent sensitivity and specificity (AUC 1.000) to differentiate periodontal health from periodontitis with a cutoff concentration equal to 1.325 ng/mL. The AUCs of E-cadherin to differentiate grade A from grade B and C periodontitis were 0.731 (cutoff point = 1.754 ng/mL) and 0.746 (cutoff point = 1.722 ng/mL), respectively. However, the AUC of salivary E-cadherin to differentiate grade B from grade C periodontitis was lower (0.541). Additionally, BOP and PPD were significantly and positively correlated with the concentration of salivary E-cadherin.

CONCLUSION

Salivary E-cadherin exhibited excellent sensitivity and specificity to differentiate periodontitis from a healthy periodontium. The level of accuracy of E-cadherin was also sufficient to recognize grade A periodontitis from grade B and C periodontitis.

Accuracy of aMMP-8 point-of-care test in indicating periodontal treatment outcomes in stage III/IV periodontitis: A 24-week follow-up study

OBJECTIVE

To analyse the correspondence between aMMP-8 PoC test results and the clinical endpoints of non-surgical periodontal treatment in stage III/IV periodontitis.

BACKGROUND

The diagnostic success of the active-matrix metalloproteinase-8 (aMMP-8) point-of-care (PoC) test has been demonstrated in various studies, but the evidence of its accuracy following periodontal treatment is limited.

MATERIALS AND METHODS

Altogether 42 stage III/IV grade C periodontitis patients were included in this prospective diagnostic study. Clinical periodontal indices were recorded, aMMP-8 PoC test was applied and mouthrinse was collected before and at 6, 12 and 24 weeks after non-surgical periodontal treatment. Quantitative aMMP-8 levels were determined with immunofluorometric assay (IFMA) for the verification of the PoC test results. The accuracy of the aMMP-8 PoC test was assessed using previously established clinical endpoints as references.

RESULTS

Sensitivity and specificity of aMMP-8 PoC test to indicate clinical endpoints were ranged as follows: Sensitivity 71.4% at baseline, 39.3%-42.4% at week 6, 28.6%-32.4% at week 12 and 35.3%-42.9% at week 24; specificity 64.3%-80% at week 6, 40%-57.1% at week 12 and 56%-64.3% at week 24.

CONCLUSIONS

The accuracy of aMMP-8 PoC test in identifying clinical endpoints after non-surgical periodontal treatment is reduced in relation to baseline. Individual healing patterns of each diseased pocket eventually limit the accuracy of the dichotomous aMMP-8 oral rinse test during the post-treatment period.

The Role of Matrix Metalloproteinases (MMP-8, MMP-9, MMP-13) in Periodontal and Peri-Implant Pathological Processes

Severe periodontitis, a destructive inflammatory disease of the supporting tissues of the teeth, ranks sixth in terms of global spread, affecting about 11% of the population. Metalloproteinases (MMPs) are extracellular matrix (ECM) macromolecules that are important in cellular development and morphogenesis, and they are capable of activating growth factors in their proximity, cell surface receptors, and adhesion molecules. MMPs are part of a major family of zinc-dependent endopeptidases, and their activity is modulated and regulated by certain inhibitors known as tissue metalloproteinase inhibitors (TIMPs). Because type I collagen is the major component of the periodontal extracellular matrix, special attention has been paid to the role of collagenases, especially MMP-8 and MMP-13 and gelatinases, MMP-2 and MMP-9, in periodontal diseases. In fact, MMP-8 (or collagenase 2) is currently one of the most promising biomarkers for periodontitis in oral fluids. Among them, salivary MMP-9 has been shown to be a more sensitive marker for periodontal inflammation during orthodontic treatment, which opens new perspectives in reducing periodontal hazards during such treatments. Both MMP-8 and MMP-9 are extremely valuable diagnostic tools in treating periodontitis, and future studies and healthcare policies should focus on implementing more accessible methods of chairside testing in order to reduce the prevalence of this disease.

Cigarette smoking and its consequences on periodontal health in teenagers: a cross-sectional study

OBJECTIVES

Smoking has been extensively investigated as a risk factor for periodontal disease and many studies have confirmed it. The aim of this study was to show data from Croatia on periodontal health among high school students, with the focus on association of tobacco use and oral hygiene habits, and the periodontal parameters.

METHODS

Pocket probing depth (PPD), bleeding on probing, supragingival calculus, and oral hygiene habits were recorded for each examinee out of 517 high school students. PPD was measured at 4 interproximal sites on all first molars and central incisors (index teeth).

RESULTS

There were 34.6% smokers among subjects, who started smoking on average at the age of 14. More than half of the smokers (55.3%) smoked 1-10 cigarettes per day and intensity of smoking increased with age. PPD was significantly greater (p = 0.012) in smokers (1.69 mm) than in non-smokers (1.59 mm). In non-smoking subjects, increased values of PPD were in direct proportion to the reduced frequency of brushing, while there was no difference in smokers. The number of cigarettes smoked and duration of smoking had a great influence on PPD. Smokers had on average more teeth with supragingival calculus than non-smokers, while non-smokers had more bleeding on probing, and the difference was statistically significant (p < 0.001).

CONCLUSIONS

This study indicated that cigarette smoking was associated with decreased periodontal health even in this young population. Irregular oral hygiene was associated with decreased periodontal health only in non-smokers. Therefore, it should be important to inform young smokers about the negative effects of cigarette smoking on periodontal health, to provide consultations and reinforce smoking prevention measures.

Human leukocyte antigens are associated with salivary level of active MMP-8

Objectives

This case control study examined the associations of HLA antigens and periodontitis with the salivary level of active MMP‐8 (aMMP‐8).

Materials and Methods

A total of 202 subjects, registered as Swiss bone marrow donors, participated in the study. HLA‐A, ‐B, and ‐C types were determined by serology or PCR. Saliva samples were collected from subjects, followed by a periodontal examination. The salivary level of aMMP‐8 was determined with immunofluorometric assay.

Results

The mean salivary level of aMMP‐8 was directly comparable to the grade of periodontitis and increased from healthy to mild/moderate to severe (125.0 ± 132.1, 200.6 ± 170.2, 290.1 ± 202.3 ng/ml; p < 0.001 between each group, respectively). The only association between the HLA types and the salivary level of aMMP‐8 was observed in subjects with HLA‐A11. Subjects with healthy periodontium and HLA‐A11 had a lower level of aMMP‐8 (49.2 ± 32.5 ng/ml) compared with subjects without HLA‐A11 (123.6 ± 119.2; p = 0.048). Among subjects with periodontitis, a higher level of aMMP‐8 (394.2 ± 255.6 ng/ml) was observed in subjects with HLA‐A11 compared with subjects without HLA‐A11 (201.1 ± 146.1 ng/ml; p < 0.002). This finding was statistically significant also after adjusting for sex, age, smoking, tooth brushing and the number of medications (p < 0.05).

Conclusions

HLA‐A11 is associated with the salivary level of aMMP‐8 which contributes to the subject's immune and inflammatory response in periodontium.

Saliva as a Source of Biomarkers for Periodontitis and Periimplantitis

Saliva has the potential to be used as a diagnostic and monitoring tool for various diseases if biomarkers of an adequate sensitivity and specificity could be identified. Several reviews and even meta-analyses have been performed in recent years, which have found some candidate biomarkers for periodontitis, like macrophage inflammatory protein-1 alpha, interleukin-1ß, interleukin-6, matrix metalloproteinase-8, or hemoglobin. However, none of those are currently in use to replace conventional periodontal diagnostics with a periodontal probe. For periimplantitis, to date, heterogeneity of different study protocols and implant types did not permit to discover clear biomarkers, which were able to distinguish between healthy and diseased implants. Few proinflammatory cytokines, similar to periodontitis, have been characterized as adjunct tools to clinical diagnosis. The additional determination of antimicrobial peptides, bone turnover markers, and bacteria could help to enhance sensitivity and specificity in a combined model for periodontitis and periimplantitis. Furthermore, proteomic approaches might be preferred over single biomarker determinations. A global consensus is also needed to harmonize salivary sampling methods as well as procedures of biomarker analysis to ensure future comparability.

Low association between bleeding on probing propensity and the salivary aMMP-8 levels in adolescents with gingivitis and stage I periodontitis

BACKGROUND AND OBJECTIVE

Bleeding on probing (BOP) is a widely accepted measure used in periodontal diagnostics. Previous studies suggest that several factors can affect BOP propensity. The aim of this study was to investigate the relative impact of different local and modifying factors on BOP levels.

MATERIALS AND METHODS

The oral health of five hundred and forty-four adolescents (two birth cohorts) aged 15-17 years living in Kotka, Finland, was examined including periodontal probing depth, visible plaque index, root calculus, and BOP. Whole saliva samples were collected and measured for active matrix metalloproteinase-8 (aMMP-8) by time-resolved immunofluorometric assay (IFMA).

RESULTS

Bacterial plaque/calculus accumulation (oral hygiene) had a major influence on BOP levels. The relative impact was several times greater compared with the extent of periodontal pocketing, aMMP-8 levels, smoking, toothbrushing, or gender. Furthermore, BOP levels were significantly elevated among adolescents with poor oral hygiene than good oral hygiene even if adjusted for the extent of periodontal pocketing (P < .001). BOP levels could be low even if several ≥ 4 mm deep periodontal pockets existed. The difference in the extent of periodontal pocketing was not significant between the two birth cohorts of adolescents (P = .731).

CONCLUSIONS

BOP levels can be regarded as an important indicator of the extent of bacterial challenge and its adverse effects on the gingival inflammation. However, the level of oral hygiene may mask the association between the extent of gingival bleeding and the severity of the periodontal inflammatory condition. Thus, relying on BOP levels (below 10% or 20%) may provide insufficient information about the periodontal treatment need of an adolescent depending on his/her level of oral hygiene. Yet, more research is needed to confirm the results, also in adult populations.

Diagnostic Accuracy of Oral Fluids Biomarker Profile to Determine the Current and Future Status of Periodontal and Peri-Implant Diseases

Severe periodontitis is ranked as the sixth most prevalent disease affecting humankind, with an estimated 740 million people affected worldwide. The diagnosis of periodontal diseases mainly relies upon assessment of conventional clinical parameters. However, these parameters reflect past, rather than current, clinical status or future disease progression and, likely, outcome of periodontal treatment. Specific and sensitive biomarkers for periodontal diseases have been examined widely to address these issues and some biomarkers have been translated as point-of-care (PoC) tests. The aim of this review was to provide an update on PoC tests for use in the diagnosis and management of periodontal diseases. Among the PoC tests developed so far, active matrix metalloproteinase-8 has shown promising results in terms of diagnostic and prognostic values. However, further studies are required to increase the sensitivity and specificity via combining more than one biomarker and merging these test kits with periodontal risk assessment tools. Furthermore, the validity of these test kits needs to be investigated by applying the results in further independent studies and the impact on these test kits', together with the results of risk factors for periodontal diseases, such as diabetes and smoking, also needs to be examined.

Potential Effect of Tobacco Consumption through Smoking and Chewing Tobacco on IL1beta Protein Expression in Chronic Periodontitis Patients: In Silico Molecular Docking Study

Detrimental effect of bad oral habits, such as smoking and chewing tobacco, on chronic periodontitis (CP) manifest chronic inflammation of gingival tissues which majorly results in gum bleeding, and teeth loss. A genetic association study of Interleukin 1 beta (IL1β) has been conducted in CP patients having smoking and chewing tobacco habits in regular life style. A molecular docking study has been consequently done to analyze the effect of tobacco on CP progression in depth. All statistical evaluation has been done by using SPSS v16.0. The findings of the study show the significant association of IL1β gene polymorphisms with CP increased susceptibility in combination of oral habits as mentioned earlier. The docking profile has showed the highest binding affinity of IL1β protein with the Nicotine derived Nitrosamine Ketone (NNK), one of the derivatives of nicotine which is in-taken through the habits associated with smoking and chewing tobacco. Nicotine, N-nitrosoanabasine, and N-nitrosonornicotine, the other derivatives, have also demonstrated significant impact over the IL1β protein-caused altered expression. Thus, this study concluded that the harmful effect of tobacco may increase the inflammation in periodontia by inducing the inflammatory active site of the IL1β protein in the CP patients.

Regulation of Salivary Peptidoglycan Recognition Protein 1 in Adolescents

INTRODUCTION

Peptidoglycan recognition protein 1 (PGLYRP1), a member of peptidoglycan recognition proteins, is known to be involved in the proinflammatory response toward bacterial infections. Recently, PGLYRP1 was identified as a ligand for triggering receptor expressed on myeloid cells 1 (TREM-1). Although PGLYRP1 is involved in immune and inflammatory responses, its levels in initial stages of periodontal disease in adolescents are currently unknown.

OBJECTIVES

We aimed to investigate salivary levels of PGLYRP1 and its correlation with TREM-1, polymorphonuclear leukocyte elastase (PMN elastase), and an active matrix metalloproteinase 8 (aMMP-8) in adolescents.

METHODS

Whole saliva samples (n = 537) were collected from 15- to 16-y-old adolescents at Kotka Health Center, Finland, prior to periodontal examination, including measurement of periodontal pocket depth (PPD), visible plaque index (VPI), and bleeding on probing (BOP). Adolescents, clustered as periodontally healthy, gingivitis, or subclinical periodontitis, were tested for salivary levels of TREM-1, PGLYRP1, and PMN elastase by enzyme-linked immunosorbent assay and aMMP-8 by a time-resolved immunofluorometric assay (IFMA).

RESULTS

Salivary levels of PGLYRP1 and aMMP-8 were significantly higher in adolescents with subclinical periodontitis and gingivitis compared to individuals with healthy periodontium. TREM-1 and PMN elastase levels were higher in adolescents with subclinical periodontitis compared to healthy individuals but did not reach significance. PGLYRP1 correlated positively with BOP, PPD, VPI, aMMP-8, and TREM-1.

CONCLUSIONS

Elevated PGLYRP1 levels in adolescents with gingivitis and subclinical periodontitis and its positive correlation with TREM-1 and aMMP-8 may indicate an association of PGLYRP1 with initial stages of periodontal disease. Sex and poor oral hygiene but not smoking are also associated with higher levels of PGLYRP1. However, PGLYRP1 has a lower discriminating capacity and is therefore a less reliable marker alone in the diagnosis of initial stages of periodontal disease in adolescents.

KNOWLEDGE TRANSFER STATEMENT

PGLYRP1, a member of peptidoglycan recognition proteins, is a ligand for TREM-1. Elevated PGLYRP1 levels in adolescents with gingivitis and subclinical periodontitis and its positive correlation with TREM-1 and aMMP-8 may indicate an association of PGLYRP1 with initial stages of periodontal disease. However, it has a lower discriminating capacity and is therefore a less reliable marker alone in the diagnosis of periodontal disease in adolescents.

The Connection of Periodontal Disease and Diabetes Mellitus: The Role of Matrix Metalloproteinases and Oxidative Stress

Diabetes mellitus, a chronic disease considered by the World Health Organization to be an epidemic, is now recognized as one of the factors behind the onset of periodontal disease. The connection between periodontal disease, which is an irreversible inflammatory disease of the supporting tissue of the teeth, and systemic diseases is reflected in the existence of common risk factors, subgingival dental biofilm, as a constant source of proinflamma-tory cytokines synthesized intensely in inflammatory periodontium. Diabetes mellitus leads to increased oxidative stress in periodontal tissues causing worsening of the disease and periodontopathy exacerbates deficiency of pancreatic β-cells. The most important role in primary inflammatory response in the pathogenesis of periodontopathy is played by neutrophils. Neutrophils cause periodontium destruction by the release of enzymes (matrix metalloproteinases), cytotoxic substances (free radicals, reactive oxygen and nitrogen species) and the expression of membrane receptors. Matrix metalloproteinases within the “protease network” are critical to many physiological and pathological processes, including immunity, inflammation, bone resorption and wound healing. Matrix metalloproteinases levels are elevated in patients with metabolic syndrome and diabetes mellitus, which may contribute to more frequent complications. In this paper, the review of available literature data shows the correlation between periodontal disease and diabetes mellitus, as well as the role of matrix metalloproteinases and oxidative stress in these. In this regard, determining the value of matrix metalloproteinases may be helpful in the diagnosis of periodontal disease complicated by diabetes mellitus. Also, the parameters of oxidative stress could help to clarify the mechanisms of pathogenesis and etiology of periodontal disease, or indicate the potential benefit of antioxidant supplementation in these individuals. As the role of matrix metalloproteinases has not been fully clarified in the pathogenesis of periodontopathy, additional studies will be needed to indicate their importance.

Global Prevalence of Tobacco Use in Adolescents and Its Adverse Oral Health Consequences

BACKGROUND:

Smoking is associated with various systemic conditions and contributes to a huge financial burden to economies around the world.

AIM:

The study aimed to evaluate global data about the prevalence of tobacco use among male and female adolescents and to discuss smoking-related oral complications.

METHODS:

The prevalence data of tobacco use among adolescents (13-15 years) was retrieved from the World Health Organization (Global Health Observatory). The World Bank’s statistics about gross national income (GNI) per capita were used to categorise low-income, lower-middle-income, upper-middle-income, and high-income countries. PubMed, Web of Science, Scopus, and Embase databases were searched to gather updated evidence about the adverse consequences of smoking on oral health among adolescents.

RESULTS:

The prevalence of tobacco use was 19.33%, and there were 23.29% of male and 15.35% female smoker adolescents in 133 countries (p < 0.001). The highest prevalence of tobacco use in male (24.76%) and female (19.4) adolescents was found in high-income countries. Significantly higher proportions of male adolescents were smokers than female counterparts in low-income, lower-middle-income, and upper-middle-income (p < 0.001). However, there were no statistically significant differences in tobacco use between male and female adolescents in high-income countries. Low-income countries had the lowest prevalence (14.95%) of tobacco use, while high-income countries had the highest prevalence estimates (22.08). Gingivitis (72.8%), gingival bleeding (51.2%), oral malodor or halitosis (39.6%) is common oral conditions among smoker adolescents. Smoking habit is significantly associated with dental caries, periodontal disease, hairy tongue, smoking-related melanosis, and hyperkeratosis among adolescents.

CONCLUSION:

There was a high prevalence of tobacco use among male and female adolescents around the globe. Available evidence suggests a strong association between smoking and compromised oral health among adolescents. Globally, measures should be taken to prevent and control the menace of tobacco use to reduce systemic and oral complications.

Curcumin inhibits the expression of proinflammatory mediators and MMP-9 in gingival epithelial cells stimulated for a prolonged period with lipopolysaccharides derived from Porphyromonas gingivalis

Curcumin, a yellow phytochemical found in the rhizomes of Curcuma longa, has various biological effects, including anti-oxidant and anti-inflammatory activities. In the present study, we examined the effect of curcumin on the expression of inflammatory cytokines in human gingival epithelial progenitor cells (HGEPs) stimulated for a prolonged period with lipopolysaccharide (LPS) derived from Porphyromonas gingivalis. The cells were alternately cultured with LPS and/or curcumin every 3 days for 18 days. The expression levels of TNF-α, IL-1β, IL-6, TIMP-1, and MMP-9 in the HGEPs were evaluated by quantitative real-time polymerase chain reaction. Enzyme-linked immunosorbent assay was used to measure the concentrations of these five proteins in the supernatant and nuclear factor (NF)-κB in the nuclear extracts. Curcumin inhibited the mRNA expression levels of TNF-α, IL-1β, IL-6, and MMP-9 in HGEPs treated with curcumin over a prolonged period. Similarly, the expression levels of IL-1β, IL-6, and MMP-9 were decreased in the culture supernatants. NF-κB activity was also inhibited in the cells cultured with curcumin. In conclusion, these findings indicate that curcumin inhibits the expression of inflammatory cytokines and MMP-9 in primary gingival epithelial cells stimulated with P. gingivalis-derived LPS via NF-κB activation.

Quantile-based fecal hemoglobin concentration for assessing colorectal neoplasms with 1,263,717 Taiwanese screenees

Background

Although fecal hemoglobin concentration (f-Hb) was highly associated with the risk of colorectal neoplasms, current studies on this subject are hampered by skewedness of the data and the ordinal property of f-Hb has not been well studied yet. Our aim was to develop a quantile-based method to estimate adjusted percentiles (median) of fecal hemoglobin concentration and their derived prediction for the risk of multistage outcomes of colorectal disease.

Methods

We used a 6-year follow-up cohort of Taiwanese nationwide colorectal screening program with fecal immunochemical testing (FIT) to obtain fecal hemoglobin concentration and applied accelerated failure time multi-variable analyses to make the comparison of adjusted median and other percentitles of fecal hemoglobin across four categories of colorectal carcinogenesis. We then predicted the risk of colorectal neoplasms on the basis of the corresponding percentile values by using accelerated failure time model with Bayesian inversion method.

Results

The adjusted median fecal hemoglobin concentration of nonadvanced adenoma, advanced adenoma, and colorectal cancer were 57, 82, and 163 μg/g feces as opposed to 0 μg/g feces for the normal group. At 90 μg/g of f-Hb, the highly suspected cut-off for colorectal disease, the risks were 17% for non-advanced adenoma, 6% for advanced adenoma, and 9% for CRC. Life-time risks of each colorectal neoplasm were derived by percentiles of fecal hemoglobin concentration.

Conclusion

Covariate-adjusted risk stratification for multistage outcomes of colorectal neoplasia were provided by using the quantiles of fecal hemoglobin concentration, yielding the estimated life-time risks of 25th to 75th quantitles, ranging from 0.5 to 44% for colorectal cancer, 0.2 to 46% for non-advanced adenoma, and 0.1 to 20% for advanced adenoma.

Electronic supplementary material

The online version of this article (10.1186/s12911-019-0812-1) contains supplementary material, which is available to authorized users.

Smoking confounds the periodontal diagnostics using saliva biomarkers

BACKGROUND

Smoking is a risk factor for periodontal disease because of its complex impact on the inflammatory response in the periodontium. We investigated the effect of smoking on salivary periodontal biomarkers, matrix metalloproteinase (MMP)-8, MMP-9, tissue inhibitor of metalloproteinase (TIMP)-1 and myeloperoxidase (MPO).

METHODS

Saliva biomarkers were analyzed in the Parogene population (n = 480) comprising a random cohort of patients that have undergone coronary angiography and oral examination. The effect of time since cessation and pack years of smoking on biomarkers were investigated.

RESULTS

Saliva MMP-8, MMP-9, TIMP-1, and MPO concentrations distinguished periodontitis patients significantly from patients without periodontitis. When the time since cessation was considered, the area-under-the-curve values (p-value) for periodontitis were 0.76 (<0.001), 0.74 (<0.001), 0.70 (<0.001), and 0.76 (<0.001), respectively. Adding information about smoking habits in the models improved slightly the sensitivities of all biomarkers. In logistic regression model saliva, MMP-8 was mainly affected by pack years of smoking, whereas saliva MMP-9, TIMP-1, and MPO were mostly affected by time since cessation, especially if smoking currently or quit recently (<1 year ago).

CONCLUSION

Smoking confounds the salivary diagnostics of periodontitis and should be considered when interpreting the results obtained by potential diagnostic tests.

Cross-sectional analysis of risk factors for subclinical periodontitis; active matrix metalloproteinase-8 as a potential indicator in initial periodontitis in adolescents

BACKGROUND

The aim of this study was to investigate how different patient-related risk indicators might be associated with the odds of developing subclinical periodontitis in adolescents.

METHODS

This cross-sectional study included 252 Finnish individuals aged 15 to 16 years, of whom 141 were boys and 111 girls. A specially trained dentist performed clinical examinations: measurements included periodontal indexes (bleeding on probing, visible plaque index, root calculus, and probing depth, smoking by pack-years, periodontal bacteria (Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Prevotella intermedia, Prevotella nigrescens, and Treponema denticola) and the potential salivary periodontal biomarkers (active matrix metalloproteinase-8 [aMMP-8], polymorphonuclear leukocyte elastase [PMN elastase], and total protein, albumin, immunoglobulin A, immunoglobulin G, and immunoglobulin M). Results were analyzed by ordinal logistic regression, one-way analysis of variance, Fisher exact test, and Kruskal-Wallis H test.

RESULTS

The main finding of this study was that subclinical periodontitis in adolescents was statistically significantly associated with elevated salivary aMMP-8 but not with PMN elastase. Also, adolescents with subclinical periodontitis had statistically significantly higher levels of bleeding on probing, root calculus, and dental plaque than adolescents without subclinical periodontitis.

CONCLUSIONS

We suggest that the main risk factor for subclinical periodontitis in adolescents is the partly calcified, dysbiotic bacterial biofilm, which interacts with the immune defenses of the host; this leads to gingival inflammation and eventually to deepening periodontal pockets. This proinflammatory subclinical periodontitis stage, which represents stage I periodontitis in the new classification, is reflected as elevated salivary aMMP-8 levels in oral fluids.

Matrix Metalloproteinase-8 as an Inflammatory and Prevention Biomarker in Periodontal and Peri-Implant Diseases

Levels of and especially the degree of activation of matrix metalloproteinase (MMP-8) in oral fluids (i.e., saliva, mouth rinse, gingival crevicular fluid (GCF) and peri-implantitis sulcular fluid (PISF)) increase to pathologically elevated levels in the periodontal and peri-implant diseases. This study aimed at collecting and collating data from previously published studies and determining whether active MMP-8 (aMMP-8) could serve as a biomarker for the diagnosis and prevention of periodontal and peri-implant diseases. The literature search identified a total of 284 articles. Out of 284 articles, 61 articles were found to be relevant. Data obtained from the selected studies were combined, and it indicated that aMMP-8 in oral fluids exerts the strong potential to serve as a useful adjunctive diagnostic and preventive biotechnological tool in periodontal and peri-implant diseases. aMMP-8 can be used alone or in combination with other proinflammatory and/or microbiological biomarkers.

Stress-related hormones in association with periodontal condition in adolescents-results of the epidemiologic LIFE Child study

OBJECTIVES

The aim of this study was to investigate the associations between blood levels of stress-related hormones and early signs of periodontal disease in children and adolescents.

MATERIALS AND METHODS

Within the LIFE (Leipzig research center for civilization diseases) Child study, 498 adolescents (10 to 18 years) were included. Early signs of periodontal inflammation were measured by probing depth (PD) at six index teeth (16, 11, 26, 36, 31, 46). Blood levels of stress-related hormones (cortisol, dehydroepiandosterone-sulfate [DHEA-S]) and, additionally interleukine-6 (IL-6) were measured. Socioeconomic status, oral hygiene, orthodontic appliances, and nutritional status, recorded by body-mass-index-standard-deviation-score (BMI-SDS), were considered as confounding factors. Additionally, in 98 participants, an oral chairside active matrix metalloproteinase-8 (aMMP-8) test was performed. Statistical tests are the Mann-Whitney U tests, chi-squared tests and multivariate logistic regression model.

RESULTS

IL-6, BMI-SDS as well as positive aMMP-8 test result were significantly associated with maximum PD > 3 mm (p < 0.05). However, no statistically significant associations between stress-related hormones (cortisol and DHEA-S) and presence of maximum PD > 3 mm were found (p > 0.05). Higher DHEA-S and BMI were associated with positive aMMP-8 result, even after adjusting for age and gender (p = 0.027, p_adj = 0.026).

CONCLUSION

The results reveal no associations between PD and stress-related hormones cortisol and DHEA-S. aMMP-8 test result might be associated with DHEA-S level. Nutritional status seems to influence periodontal disease in adolescents.

CLINICAL RELEVANCE

DHEA-S and BMI-SDS show associations with early signs of periodontal disease in adolescents aged 10 to 18 years. This association should be confirmed by the investigation of high-risk groups.

Matrix metalloproteinase-8 analysis in patients with periodontal disease with prediabetes or type 2 diabetes mellitus: A systematic review

OBJECTIVES

The objective of this systematic review was to evaluate information on the levels of MMP-8 in patients diagnosed with prediabetes or type 2 diabetes mellitus with periodontal disease, analyzing its validity as a possible biomarker for the diagnosis and progression of periodontal disease (PD).

METHODS

A systematic search of the following databases was performed: PubMed/Medline, CENTRAL (The Cochrane Library), EMBASE and Web of Science. Studies involving the evaluation of MMP-8 in patients with prediabetes or patients presenting type 2 diabetes mellitus concomitantly with PD were selected. The evaluation of the methodological quality of the selected studies was based on the methodological bias risk analysis (QUADAS-2).

RESULTS

Eight of the initially identified 2683 articles were selected. In all the selected studies, evaluator calibration and the use of clear methods for patient diagnosis with periodontal disease were present. Studies have demonstrated significantly higher MMP-8 concentrations in PD patients compared to controls, as well as in patients presenting more advanced stages of PD. However, controversies regarding MMP-8 levels in prediabetes/diabetes type 2 patients with PD.

CONCLUSIONS

Higher MMP-8 levels in patients with PD compared to controls imply the potential use of MMP-8 in the diagnosis of PD. The influence of patient glycemic state, as well as medications these patients make use of, are factors that possibly contribute to the modulation of MMP-8 concentrations in patients with diabetes and should be analyzed, aiming at a better understanding of the relationship between glycemic state and MMP-8 levels in patients with PD.

Associations of oral fluid MMP-8 with periodontitis in Swiss adult subjects

OBJECTIVE

MMP-8 is a prominent collagenase in periodontal disease. This cross-sectional study examined whether MMP-8 levels in saliva and gingival crevicular fluid (GCF) are associated with periodontitis in a Swiss population.

SUBJECTS AND METHODS

A total of 258 subjects (107 m, 151 f, mean age: 43.5 yr; range: 21-58 yr) acquired from the Swiss bone marrow donor registry participated in the study. Saliva and GCF samples were collected from subjects followed by a thorough dental and periodontal examination. MMP-8 levels were determined with immunofluorometric assay. Associations of MMP-8 levels with periodontal diagnosis, probing pocket depth (PPD) and bleeding on probing were statistically analysed with Pearson chi-square test, Spearman's rho and logistic regression analysis.

RESULTS

MMP-8 in GCF correlated with MMP-8 in saliva (p < .001). Periodontitis was more common (p < .001) among subjects with high levels of MMP-8 in saliva and/or GCF compared with subjects with low levels of MMP-8. Higher MMP-8 levels in GCF and saliva were associated with any periodontal diagnosis (mild, moderate or severe), greater PPD, and bleeding on probing (p < .05). When age, gender, smoking, body mass index, number of medications and decayed, missing and filled teeth were adjusted for, all observed associations remained statistically significant. The area under curve of receiver-operating characteristic was 0.67 for saliva and 0.71 for GCF.

CONCLUSION

Elevated MMP-8 levels both in saliva and GCF are associated with periodontitis in a normal adult population.

Matrix metalloproteinase-8 levels in periodontal disease patients: A systematic review

Periodontal disease is characterized as a disorder of the oral microbiota resulting in an immune response which, in turn, leads to the destruction of periodontal tissue. Matrix metalloproteinase-8 (MMP-8) has been reported as the major metalloproteinase involved in periodontal disease, being present at high levels in gingival crevicular fluid and salivary fluid (SF). The aim of this systematic review was to evaluate the scientific literature regarding the expression of MMP-8 in gingival crevicular fluid and SF in patients with periodontal disease, analyzing its validity as a possible biomarker in the diagnosis of periodontal disease. A systematic review of the literature was performed using the PubMed/Medline, CENTRAL and Science Direct databases. Studies concerning the use of MMP-8 in the diagnosis of periodontal disease that evaluated its effectiveness as a biomarker for periodontal disease were selected. The search strategy provided a total of 6483 studies. After selection, six articles met all the inclusion criteria and were included in the present systematic review. The studies demonstrated significantly higher concentrations of MMP-8 in patients with periodontal disease compared with controls, as well as in patients presenting more advanced stages of periodontal disease. The findings on higher MMP-8 concentrations in patients with periodontal disease compared with controls imply the potential adjunctive use of MMP-8 in the diagnosis of periodontal disease.

Effect of saliva collection methods and oral hygiene on salivary biomarkers

The aim of this study was to evaluate the influence of unstimulated and stimulated saliva collection methods, as well as tooth brushing, on the secretion rate of salivary total protein, nitrite, total antioxidant capacity and alpha-amylase. Saliva of 14 healthy individuals were collected with stimulation using Salivette^®, Parafilm^® and chewing gum and without stimulation from spit with and without fluid accumulation, before and after oral hygiene. Total protein, nitrite, total antioxidant capacity and alpha-amylase concentration (sAA) were evaluated. The collection of saliva stimulated with Parafilm^® and chewing gum increased the salivary flow (1.5 ± 0.4 and 3.4 ± 0.7 mL/min, respectively) and the secretion rate of salivary total protein (1.0 ± 0.2 and 2.3 ± 0.5 mg/min, respectively). Also, chewing gum increases the salivary nitrite secretion (213 ± 58 nmol/min) and total antioxidant capacity (410 ± 47 nmol trolox eq/min). Interestingly, the unstimulated method without saliva accumulation prior to collection resulted in low sAA levels (23,531 ± 7979 pixel density). Furthermore, oral hygiene decreased salivary flow (1.3 ± 0.5 to 1.0 ± 0.4 mL/min), reduced the secretion rate of total protein (1.0 ± 0.5 to 0.6 ± 0.2 mg/min, p < .05) and increased sAA (13,159 ± 7114 to 20,075 ± 25,656 pixel density, p < .05). The type of stimulation can activate autonomous receptors responsible for the secretion and composition of saliva. Therefore, the evaluation of saliva collection methods and oral hygiene on salivary biomarkers is important for understanding and standardizing variations in salivary composition to strengthen the use of saliva as a diagnostic fluid.

aMMP-8 in correlation to caries and periodontal condition in adolescents-results of the epidemiologic LIFE child study

OBJECTIVES

The suitability of a chairside aMMP-8 test in determination of periodontal inflammation and caries in adolescents was assessed. Secondly, the influence of orthodontic treatment on aMMP-8 test result was analyzed.

MATERIALS AND METHODS

Within the LIFE Child study, 434 adolescents (10 to 18 years) were included. Clinical dental examinations comprised caries experience (DMF/T-Index), signs of periodontal inflammation (probing pocket depth, PPD; community periodontal index of treatment needs; CPITN) at six index teeth and oral hygiene (OH). Information about orthodontic appliances (OA) and socioeconomic status (SES) were obtained by validated questionnaires. Test's sensitivity and specificity to detect periodontal inflammation and carious lesions were evaluated. The influence of OA on the test result was analyzed (multivariate model).

RESULTS

No associations between age, gender, SES or OH, and test outcome were found (p > 0.05). Positive test results correlated to periodontal findings (CPITN, mean PPD; p < 0.001). However, for the detection of ≥ 1 site(s) with PPD ≥ 4 mm, the test's sensitivity and specificity were found to be 61 and 69%, respectively. Multivariate analysis revealed a higher probability for a positive test result in cases of fixed OA (odds ratio 5.02, 95% confidence interval 1.90-13.19). The test had no diagnostic value considering carious lesions.

CONCLUSIONS

The chairside aMMP-8 test does not reliably identify adolescents with periodontal inflammation. Positive test results were more frequent in case of OA.

CLINICAL RELEVANCE

The chairside aMMP-8 test is no appropriate tool to screen children and adolescents neither for periodontal inflammation nor for carious lesions.

Matrix Metalloproteinases as Regulators of Periodontal Inflammation

Periodontitis are infectious diseases characterized by immune-mediated destruction of periodontal supporting tissues and tooth loss. Matrix metalloproteinases (MMPs) are key proteases involved in destructive periodontal diseases. The study and interest in MMP has been fuelled by emerging evidence demonstrating the broad spectrum of molecules that can be cleaved by them and the myriad of biological processes that they can potentially regulate. The huge complexity of MMP functions within the 'protease web' is crucial for many physiologic and pathologic processes, including immunity, inflammation, bone resorption, and wound healing. Evidence points out that MMPs assemble in activation cascades and besides their classical extracellular matrix substrates, they cleave several signalling molecules-such as cytokines, chemokines, and growth factors, among others-regulating their biological functions and/or bioavailability during periodontal diseases. In this review, we provide an overview of emerging evidence of MMPs as regulators of periodontal inflammation.

Inflammatory mediator polymorphisms associate with initial periodontitis in adolescents

Several studies have addressed cytokine gene polymorphisms and their possible associations with periodontitis. We examined the association between salivary anti- and pro-inflammatory mediator polymorphisms and initial periodontitis in Finnish adolescents, taking into account the effect of smoking. Salivary samples of 93 clinically examined adolescents from Eastern Finland were analyzed. Their oral health and smoking habits were recorded. Periodontal probing depth (PPD), and bleeding on probing (BOP) at four sites per tooth, root calculus (RC), and visible plaque index (VPI) were recorded from the index teeth. Salivary MMP-8 median values were assessed. The sites with ≥4 mm PD were categorized as follows: PPD1 = one or more ≥4 mm pocket, PPD2 = two or more ≥4 mm pockets, and PPD3 = three or more ≥4 mm pockets. Genomic DNA was extracted from 300 μl of the saliva samples by genomic QIAamp® DNA Blood Mini Kit and genotyped for polymorphisms. Genetic variants for genotyping were selected from the following genes of interest: S100A8, FCGR2A, FCGR2B, IL10, MMP8, MMP3, MMP13, VDR, TLR4, MMP2, MPO, ELANE, IL1A, IL1B, IL1RN, CD28, MMP9, DDX39B, NFKBIL1, LTA, TNF, SOD2, IL6, TLR4, TIMP1, and SYN1. After false discovery rate control (FDR), polymorphisms in MMP3 (rs679620, rs520540, rs639752), CD28 (rs3116496), and VDR (rs2228570) associated (FDR q < 0.05) with deepened periodontal pockets. Smoking did not affect the results. Genetic polymorphisms of pro-inflammatory mediators MMP3, CD28, and VDR seem to link to initial periodontitis.

Rapid assessment of salivary MMP-8 and periodontal disease using lateral flow immunoassay

OBJECTIVE

The objective of this study was to determine the efficacy of a novel point-of-care immunoflow device (POCID) for detecting matrix metalloproteinase (MMP)-8 concentrations in oral fluids in comparison with a gold standard laboratory-based immunoassay.

METHODS

Oral rinse fluid and whole expectorated saliva samples were collected from 41 participants clinically classified as periodontally healthy or diseased. Samples were analyzed for MMP-8 by Luminex immunoassay and POCID. Photographed POCID results were assessed by optical scan and visually by two examiners. Data were analyzed by Pearson's correlation and receiver-operating characteristics.

RESULTS

MMP-8 was readily detected by the POCID, and concentrations correlated well with Luminex for both saliva and rinse fluids (r = 0.57-0.93). Thresholds that distinguished periodontitis from health were delineated from both the optical scans and visual reads of the POCID (sensitivity: 0.7-0.9, specificity: 0.5-0.7; P < 0.05).

CONCLUSIONS

Performance of this POCID for detecting MMP-8 in oral rinse fluid or saliva was excellent. These findings help demonstrate the utility of salivary biomarkers for distinguishing periodontal disease from health using a rapid point-of-care approach.

Association of Common Variants in MMPs with Periodontitis Risk

Background. Matrix metalloproteinases (MMPs) are considered to play an important role during tissue remodeling and extracellular matrix degradation. And functional polymorphisms in MMPs genes have been reported to be associated with the increased risk of periodontitis. Recently, many studies have investigated the association between MMPs polymorphisms and periodontitis risk. However, the results remain inconclusive. In order to quantify the influence of MMPs polymorphisms on the susceptibility to periodontitis, we performed a meta-analysis and systematic review. Results. Overall, this comprehensive meta-analysis included a total of 17 related studies, including 2399 cases and 2002 healthy control subjects. Our results revealed that although studies of the association between MMP-8 −799 C/T variant and the susceptibility to periodontitis have not yielded consistent results, MMP-1 (−1607 1G/2G, −519 A/G, and −422 A/T), MMP-2 (−1575 G/A, −1306 C/T, −790 T/G, and −735 C/T), MMP-3 (−1171 5A/6A), MMP-8 (−381 A/G and +17 C/G), MMP-9 (−1562 C/T and +279 R/Q), and MMP-12 (−357 Asn/Ser), as well as MMP-13 (−77 A/G, 11A/12A) SNPs are not related to periodontitis risk. Conclusions. No association of these common MMPs variants with the susceptibility to periodontitis was found; however, further larger-scale and multiethnic genetic studies on this topic are expected to be conducted to validate our results.

Host response mechanisms in periodontal diseases

Periodontal diseases usually refer to common inflammatory disorders known as gingivitis and periodontitis, which are caused by a pathogenic microbiota in the subgingival biofilm, including Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Tannerella forsythia and Treponema denticola that trigger innate, inflammatory, and adaptive immune responses. These processes result in the destruction of the tissues surrounding and supporting the teeth, and eventually in tissue, bone and finally, tooth loss. The innate immune response constitutes a homeostatic system, which is the first line of defense, and is able to recognize invading microorganisms as non-self, triggering immune responses to eliminate them. In addition to the innate immunity, adaptive immunity cells and characteristic cytokines have been described as important players in the periodontal disease pathogenesis scenario, with a special attention to CD4⁺ T-cells (T-helper cells). Interestingly, the T cell-mediated adaptive immunity development is highly dependent on innate immunity-associated antigen presenting cells, which after antigen capture undergo into a maturation process and migrate towards the lymph nodes, where they produce distinct patterns of cytokines that will contribute to the subsequent polarization and activation of specific T CD4+ lymphocytes. Skeletal homeostasis depends on a dynamic balance between the activities of the bone-forming osteoblasts (OBLs) and bone-resorbing osteoclasts (OCLs). This balance is tightly controlled by various regulatory systems, such as the endocrine system, and is influenced by the immune system, an osteoimmunological regulation depending on lymphocyte- and macrophage-derived cytokines. All these cytokines and inflammatory mediators are capable of acting alone or in concert, to stimulate periodontal breakdown and collagen destruction via tissue-derived matrix metalloproteinases, a characterization of the progression of periodontitis as a stage that presents a significantly host immune and inflammatory response to the microbial challenge that determine of susceptibility to develop the destructive/progressive periodontitis under the influence of multiple behavioral, environmental and genetic factors.

Salivary cytokines as a minimally-invasive measure of immune functioning in young children: correlates of individual differences and sensitivity to laboratory stress

There is growing interest in minimally-invasive measures of environmentally-responsive biological systems in developmental science. Contributing to that endeavor, this study explores the intercorrelations, correlates, and task-sensitivity of proinflammatory salivary cytokines in childhood. Saliva was sampled from 125 healthy five-year old children (49% male) across a series of cognitive and emotional challenge laboratory tasks. Samples were assayed for cytokines (IL-1β, IL-6, IL-8, TNFα), and markers of hypothalamic-pituitary-adrenal (HPA) and autonomic nervous system (ANS) activation (salivary cortisol and alpha-amylase [sAA]). Cytokines were positively intercorrelated and task-sensitivity varied. Except IL-8, cytokines were elevated in children with oral health issues and tobacco smoke exposure. Among boys, cytokines were positively related to sAA and negatively related to cortisol. The findings suggest that in healthy children, salivary cytokine levels reflect compartmentalized oral immune activity. Associations between ANS and HPA activity and cytokines in saliva may present opportunities for minimally-invasive methods to explore neuroendocrine-immune interactions during development.

Salivary diagnostics for periodontal diseases

BACKGROUND

and Overview The use of salivary diagnostics continues to develop and advance the field of risk determination for periodontal diseases. Researchers are investigating genetic, microbial and protein biomarkers with the objective of translating findings to such aspects of clinical care as broad patient screening, monitoring and treatment planning.

METHODS

/st> In this review, the author briefly explores currently available salivary diagnostics used to identify bacteria prevalent in periodontal disease, and focuses on the future development and use of a variety of rapid disease detection platforms, such as lab-on-a-chip, as a point-of-care device for identification of patients' risk.

CONCLUSIONS

and

CLINICAL IMPLICATIONS

/st> Several diagnostic tests are commercially available, and point-of-care tests are under development. However, challenges remain regarding the introduction of these technologies to clinical practice and adoption by dental practitioners for promotion of personalized oral health care.

Neutrophils alter epithelial response to Porphyromonas gingivalis in a gingival crevice model

A gingival crevice model (epithelial cell-Porphyromonas gingivalis-neutrophil) was established and used to profile gingipain, matrix metalloproteinase (MMP), MMP mediators [neutrophil gelatinase-associated lipocalin (NGAL) and tissue inhibitor of metalloproteinases 1 (TIMP-1)] and cytokine networks. Smoking is the primary environmental risk factor for periodontitis. Therefore, the influence of cigarette smoke extract (CSE) was also monitored in the same model. Porphyromonas gingivalis alone induced low levels of interleukin-1β and interleukin-8 from epithelial cells, but high levels of both cytokines were produced on the addition of neutrophils. Exposure to CSE (100 and 1000 ng ml(-1) nicotine equivalency) significantly compromised P. gingivalis-induced cytokine secretion (both P < 0.05). P. gingivalis induced impressive secretion of NGAL (P < 0.05) that was not influenced by CSE. The influence of CSE on gingipain production was strain-specific. Purified gingipains effectively and rapidly degraded both TIMP-1 and MMP-9. Induction of large amounts of NGAL, degradation of TIMP-1, and increased gingipain activity would each be expected to prolong collagen degradation and promote disease progression. However, gingipains also degrade MMP-9. Hence, P. gingivalis exerts a complex influence on the proteolytic balance of a gingival crevice model. Exposure to CSE reduces the proinflammatory cytokine burden, which may be expected to promote P. gingivalis survival. In addition to novel findings that provide mechanistic insight into periodontal disease progression, these results are in keeping with the recognized clinical dogma of decreased inflammation/increased disease in smokers. This straightforward gingival crevice model is established as a suitable vehicle for the elucidation of mechanisms that contribute to susceptibility to periodontitis.

Matrix metalloproteinases and inflammatory cytokines in oral fluid of patients with chronic generalized periodontitis and various construction materials

We present the results of comparative enzyme-linked immunosorbent assay of matrix metalloproteinases MMP-2, MMP-8, MMP-9; IL-1β and IL-6; tissue inhibitors of MMP (TIMP-1, TIMP-2), and TNF-α. The object of study was oral fluid of practically healthy subjects with intact periodontium and patients with chronic generalized periodontitis with various structural materials of dental restorations. It was found that MMP-9 in oral fluid could be considered as a marker of chronic generalized periodontitis irrespective of the presence or absence of metal dental restorations. The level of MMP-8 surpassed the normal only in oral fluid of patients with chronic generalized periodontitis with metal restorations. The correlations between the studied parameters in patients attest to relatively similar regulation of MMP, IL and TIMP secretion in oral fluid in practically healthy subjects with intact periodontium. In patients with inflammatory destructive periodontal diseases with and without metal dental restorations, the correlation coefficients indicate initiation of biochemical cascade accompanied by activation of cytokine production in response to etiological factors. Patients with periodontitis and metal orthodontic structures showed more pronounced reaction. Orthodontic structures made from chromium-cobalt, or chromium-nickel alloys in the oral cavity of these patients increased the levels of MMP-2, IL-1β and IL-6 in oral fluid.

Comparison of self-perceived oral health, periodontal inflammatory conditions and socioeconomic status in individuals with and without prediabetes

INTRODUCTION

The aim was to compare the self-perceived oral health, periodontal inflammatory conditions and socioeconomic status (SES) in patients with and without prediabetes.

METHODS

Thirty-nine individuals [19 patients with prediabetes (test group) and 20 control individuals (control group)], at least 20 years old were included. Plaque index, bleeding on probing, probing depth (4 to <6 mm and ≥6 mm) and number of missing teeth were recorded. Fasting blood glucose levels were recorded, and marginal bone loss was measured on radiographs. SES, education status, self-perceived oral health, family history of diabetes and tobacco habits were also investigated.

RESULTS

Mean ages of individuals in the test and control groups were 40.6 and 42.3 years, respectively. Plaque index, bleeding on probing, probing depth (4 to <6 mm and ≥6 mm) and number of missing teeth were higher in the test group as compared with the control group (P < 0.05). Premolar and molar marginal bone loss was higher in the test group as compared with the control group (P < 0.001). Self-perceived bleeding gums was more often reported by individuals in the test group as compared with the control group. A poor SES and education status was higher among individuals in the test group as compared with the control group (P < 0.001).

CONCLUSIONS

Self-perceived gingival bleeding and clinical periodontal inflammation were severe in patients with prediabetes as compared with controls. An underprivileged SES aggravated periodontal conditions in patients with prediabetes.

Translational and clinical applications of salivary diagnostics

There have been significant advances in techniques for the detection of biomarker signals in the oral cavity (e.g., ELISAs for proteins, PCR for RNA and DNA) as well as the engineering and development of microfluidic approaches to make oral-based point-of-care (POC) methods for the diagnosis for both local and systemic conditions a reality. In this section, we focus on three such approaches, namely, periodontal disease management, early markers for systemic diseases, and salivary markers useful for pharmacogenomic studies. Novel approaches using non-invasive, salivary samples and user-friendly devices offer results that are as sensitive and specific as laboratory-based analyses using blood or urine.

Salivary biomarkers of periodontal disease in response to treatment

BACKGROUND

Salivary biomarkers of periodontitis were assessed longitudinally to determine response to therapy.

METHODS

A 6-month case-controlled study of adults with chronic periodontitis was performed, with 33 participants receiving oral hygiene instructions (OHI) alone and 35 with scaling and root planing (SRP) combined with OHI. Saliva samples collected at week 0, 16 and 28 were analysed for interleukin (IL)-1β, IL-8, macrophage inflammatory protein (MIP)-1α, matrix metalloproteinase-8 (MMP-8), osteoprotegerin (OPG), and tumour necrosis factor-α (TNF)-α. Clinical measures of periodontal disease were recorded at each visit.

RESULTS

All parameters of periodontal health improved significantly in both groups by week 16 (p<0.0001) with the SRP group demonstrating greater benefit at week 16 and 28. Baseline OPG and TNF-α levels changed significantly at both follow-up visits (p<0.03), regardless of treatment group. IL-1β and MMP-8 levels decreased significantly from baseline (p<0.04) in the SRP group only. OPG, MMP-8, and MIP-1α were significantly reduced in responders compared with non-responders (p=0.04, 0.01, 0.05, respectively). In receiver-operating characteristic analyses, MMP-8 produced the highest area under the curve (0.7; p=0.01).

CONCLUSION

Salivary levels of IL-1β, MMP-8, OPG, and MIP-1α reflected disease severity and response to therapy suggesting their potential utility for monitoring periodontal disease status.

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.