Point-of-Care/Chairside aMMP-8 Analytics of Periodontal Diseases' Activity and Episodic Progression

Evaluating salivary MMP-8 as a biomarker for periodontal diseases: A systematic review and meta-analysis

Objective

Periodontitis is the irreversible destructive process of the periodontium and is the major cause of tooth loss in adults worldwide. Diagnosis of early-stage periodontal disease is crucial for improving outcomes, and to this end, the application of indicator biomarkers is gaining interest. One such method involves measuring the level of matrix metalloproteinase-8 (MMP-8). This systematic review and meta-analysis aims to evaluate the salivary MMP-8 level of periodontitis and gingivitis cases compared to healthy controls.

Data

We evaluated all studies that compared different laboratory techniques for measuring salivary MMP-8 levels in periodontitis and gingivitis patients, alongside healthy controls.

Sources

The systematic search was performed on 10 October 2022 in three electronic databases.

Study selection results

Pooled mean differences (MD) were calculated with 95 % confidence intervals (CIs) between the researched groups. In addition, the correlation coefficient results between MMP-8 values and other clinical parameters were narratively summarized.Based on 20 eligible studies (n = 1725), patients with periodontitis presented significantly higher MMP-8 levels (MD = 273.26 ng/ml, CI: 194.42; 352.10). Similarly, patients with gingivitis presented significantly higher salivary MMP-8 levels than healthy individuals (MD = 122.82 ng/ml, CI: 64.19; 181.45) based on the results of 10 eligible studies (n = 704). Additionally, we found higher MMP-8 levels in periodontitis compared to gingivitis (MD = 112.04 ng/ml, CI: 56.15; 167.92). The correlation results suggest that salivary MMP-8 is associated with different clinical periodontal parameters.

Conclusion

Salivary MMP-8 level measurement may be a reliable method to distinguish between periodontal health and periodontal disease and also to distinguish between gingivitis and periodontitis.

Clinical significance

The measurement of salivary MMP-8 levels may have the potential to differentiate between periodontal health and disease reliably. Accordingly, it can be considered for integration into routine dental examinations as a quick and convenient method for the early detection and prevention of periodontitis, pending further validation.

Importance of Metalloproteinase 8 (MMP-8) in the Diagnosis of Periodontitis

Periodontitis is a complex condition. Left untreated, it leads to tooth loss and the need for prosthetic treatment. The incidence of periodontitis is steadily increasing, so new methods are being sought to aid in the diagnosis of the disease. Among the methods postulated is the determination of concentrations of bioactive compounds which include extracellular matrix metalloproteinases (MMPs). These enzymes are present in various structural elements of the stomatognathic system. The most promising enzyme of this group appears to be metalloproteinase 8 (MMP-8). MMP-8 assays are performed in gingival fluid or saliva, and MMP-8 levels have been shown to be higher in patients with periodontitis compared to healthy subjects and correlated with some clinical parameters of the condition and the severity of the disease. In addition, the preliminary usefulness of this enzyme in evaluating the effectiveness of periodontal treatment and doxycycline therapy has been demonstrated. Determination of the active form of MMP-8 (aMMP-8) in oral rinse fluid using off-the-shelf assays shows the highest potential. Despite reports about aMMP-8 and promising data on the role of MMP-8 in periodontal diagnosis, a clear determination of the usefulness of this enzyme requires further research.

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.

Validation of a noninvasive aMMP‐8 point‐of‐care diagnostic methodology in COVID‐19 patients with periodontal disease

Objectives

The aim of this study was to validate an active matrix metalloproteinase (MMP‐8) point‐of‐care diagnostic tool in COVID‐19 patients with periodontal disease.

Subjects, Materials, and Methods

Seventy‐two COVID‐19‐positive and 30 COVID‐19‐negative subjects were enrolled in the study. Demographic data were recorded, periodontal examination carried out, and chairside tests run for evaluating the expression of active MMP‐8 (aMMP‐8) in the site with maximum periodontal breakdown via gingival crevicular fluid sampling as well as via a mouth rinse‐based kit for general disease activity. In COVID‐19‐positive patients, the kits were run again once the patients turned COVID‐19 negative.

Results

The overall (n = 102) sensitivity/specificity of the mouthrinse‐based kits to detect periodontal disease was 79.41%/36.76% and that of site‐specific kits was 64.71%/55.88% while adjusting for age, gender, and smoking status increased the sensitivity and specificity (82.35%/76.47% and 73.53%/88.24, respectively). Receiver operating characteristic (ROC) analysis for the adjusted model revealed very good area under the ROC curve 0.746–0.869 (p < .001) and 0.740–0.872 (p < .001) (the aMMP‐8 mouth rinse and site‐specific kits, respectively). No statistically significant difference was observed in the distribution of results of aMMP‐8 mouth rinse test (p = .302) and aMMP‐8 site‐specific test (p = .189) once the subjects recovered from COVID‐19.

Conclusions

The findings of the present study support the aMMP‐8 point‐of‐care testing (PoCT) kits as screening tools for periodontitis in COVID‐19 patients. The overall screening accuracy can be further increased by utilizing adjunctively risk factors of periodontitis. The reported noninvasive, user‐friendly, and objective PoCT diagnostic methodology may provide a way of stratifying risk groups, deciding upon referrals, and in the institution of diligent oral hygiene regimens.

Fermented lingonberry juice's effects on active MMP-8 (aMMP-8), bleeding on probing (BOP), and visible plaque index (VPI) in dental implants-A clinical pilot mouthwash study

OBJECTIVES

We aimed to study the effects of fermented lingonberry juice (FLJ) as a mouthwash on the levels of active matrix metalloproteinase-8 (aMMP-8) in peri-implant sulcular fluid (PISF), bleeding on probing (BOP), and visible plaque index (VPI). We hypothesized that FLJ rinsing could reduce inflammation (aMMP-8 and BOP) and microbial load (VPI) in the oral cavity, especially around dental implants.

MATERIALS AND METHODS

A clinical pilot study was performed using FLJ as a mouthwash. The inclusion criteria were at least one dental implant in the anterior or posterior areas with a screw-retained crown. Ten participants used 10 ml of mouthwash twice a day for 15 days, and 10 participants served as the control group. Point-of-care tests (POCTs) were used to measure aMMP-8 levels in the PISF, and BOP and VPI were recorded at the beginning of the trial and after 15 and 30 days.

RESULTS

The FLJ mouthwash had a reductive effect on aMMP-8, VPI, and BOP in the mouthwash group; however, there was no significant difference compared to the control group. The difference in VPI and BOP levels between the groups diminished after the lingonberry regimen ended. The decrease in aMMP-8 levels appeared to continue even after discontinuation of the mouthwash regimen.

CONCLUSION

The reduction in the amount of plaque, aMMP-8, and BOP by FLJ was promising and continuous considering the relatively short study period and sample size. FLJ is a natural and safe supplement for oral and dental implant home care. Further studies are required to verify these promising results.

Discovery, validation, and diagnostic ability of multiple protein-based biomarkers in saliva and gingival crevicular fluid to distinguish between health and periodontal diseases

Aim

To discover and validate differential protein biomarker expression in saliva and gingival crevicular fluid (GCF) to discriminate objectively between periodontal health and plaque‐induced periodontal disease states.

Materials and Methods

One‐hundred and ninety participants were recruited from two centres (Birmingham and Newcastle upon Tyne, UK) comprising healthy, gingivitis, periodontitis, and edentulous donors. Samples from the Birmingham cohort were analysed by quantitative mass spectrometry proteomics for biomarker discovery. Shortlisted candidate proteins were then verified by enzyme‐linked immunosorbent assay in both cohorts. Leave‐one‐out cross validation logistic regression analysis was used to identify the best performing biomarker panels.

Results

Ninety‐five proteins were identified in both GCF and saliva samples, and 15 candidate proteins were selected based upon differences discovered between the donor groups. The best performing panels to distinguish between: health or gingivitis and periodontitis contained matrix metalloproteinase‐9 (MMP9), S100A8, alpha‐1‐acid glycoprotein (A1AGP), pyruvate kinase, and age (area under the curve [AUC] 0.970); health and gingivitis contained MMP9, S100A8, A1AGP, and pyruvate kinase, but not age (AUC 0.768); and mild to moderate and advanced periodontitis contained MMP9, S100A8, A1AGP, pyruvate kinase, and age (AUC 0.789).

Conclusions

Biomarker panels containing four proteins with and without age as a further parameter can distinguish between periodontal health and disease states.

aMMP-8 Oral Fluid PoC Test in Relation to Oral and Systemic Diseases

The manuscript uses the previously published literature and highlights the benefits of active-matrix metalloproteinase (aMMP)-8 chairside/point-of-care (PoC) diagnostic tools as adjunctive measures in oral and systemic diseases. Previous studies suggest that as a biomarker, aMMP-8 is more precise than total MMP-8, MMP-9, MMP-2, MMP-3, MMP-13, MMP-7, MMP-1, calprotectin, myeloperoxidase (MPO), human neutrophil elastase (HNE), tissue inhibitor of matrix metalloproteinase (TIMP)-1, and bleeding of probing (BOP). Therefore, aMMP-8 could be implemented as the needed key biomarker for the new disease classification for both periodontitis and peri-implantitis. With a sensitivity to the tune of 75-85% and specificity in the range of 80-90%, lateral flow aMMP-8 PoC testing is comparable to catalytic protease activity assays for aMMP-8. The test can be further applied to estimate the glycemic status of an individual, to ascertain whether a person is at risk for COVID-19, in managing the oral side effects of radiotherapy carried in head and neck cancers, and in selected cases pertaining to reproductive health. In the future, aMMP-8 could find application as a potential systemic biomarker in diseases affecting the cardiovascular system, cancers, bacteremia, sepsis, diabetes, obesity, meningitis, as well as pancreatitis. The aMMP-8 PoCT is the first practical test in the emerging new dental clinical field, that is, oral clinical chemistry representing oral medicine, clinical chemistry, peri-implantology, and periodontology.

Implementing of aMMP‐8 point‐of‐care test with a modified new disease classification in Finnish adolescent cohorts

Objectives

Material and Methods

Results

Conclusions

Repeated Home-Applied Dual-Light Antibacterial Photodynamic Therapy Can Reduce Plaque Burden, Inflammation, and aMMP-8 in Peri-Implant Disease—A Pilot Study

Until now, in clinical dentistry, antibacterial photodynamic therapy (aPDT) has been restricted to in-office treatments, which hampers repeated applications. This pilot study tested the benefit of a commercially available Lumoral^® device designed for regular periodontal dual-light aPDT treatment at home. Seven patients with peri-implant disease applied dual-light aPDT daily in addition to their normal dental hygiene for four weeks. A single Lumoral^® treatment includes an indocyanine green mouth rinse followed by 40 J/cm² radiant exposure to a combination of 810 nm and 405 nm light. A point-of-care analysis of active-matrix metalloproteinase (aMMP-8), visible plaque index (VPI), bleeding on probing (BOP), and peri-implant pocket depth (PPD) measurements was performed on day 0, day 15, and day 30. Reductions in aMMP-8 (p = 0.047), VPI (p = 0.03), and BOP (p = 0.03) were observed, and PPD was measured as being 1 mm lower in the implant (p = ns). These results suggest a benefit of regular application of dual-light aPDT in peri-implantitis. Frequently repeated application can be a promising approach to diminishing the microbial burden and to lowering the tissue destructive proteolytic and inflammatory load around dental implants. Further studies in larger populations are warranted to show the long-term benefits.

Active MMP-8 point-of-care (PoC)/chairside enzyme-test as an adjunctive tool for early and real-time diagnosis of peri-implantitis

Objective

The aim of this study was to investigate the utility of the active matrix metalloproteinase (aMMP‐8)‐point‐of‐care (PoC) test as a quantitative real‐time chair‐side diagnostic tool for peri‐implant diagnosis, as well as assess the potentially developing and ongoing risk relative to the traditional clinical methods.

Background

Current peri‐implant and periodontal disease diagnoses rely on clinical and radiological examinations. This case‐control study investigated the applicability of aMMP‐8‐PoC immunotest for quantitative real‐time diagnosis and monitoring of dental implants in health and disease.

Methods

Sixty‐eight patients visiting a specialist clinic for maintenance following dental implant placement underwent assessment of their peri‐implant health. aMMP‐8‐PoC peri‐implant sulcular fluid (PISF) lateral‐flow immunotests were performed using ImplantSafe® technology quantitated by ORALyzer®. In addition, the PISF samples were analyzed for total MMP‐8, calprotectin, and interleukin (IL)‐6 by enzyme‐linked immunosorbent assays (ELISA), aMMP‐8 by western immunoblot, and MMP‐2 and MMP‐9 by gelatin zymography.

Results

The aMMP‐8‐PoC test promptly recorded and reflected peri‐implant disease, differentiating it clearly from health. X‐ray findings (bone loss > 2 mm), peri‐implant pocket depth ≥ 3 mm, and bleeding on probing were significantly more prevalent among implants positive for the aMMP‐8‐PoC test. aMMP‐8/ORALyzer analysis was more precise in recording disease than total MMP‐8, calprotectin, IL‐6, MMP‐2, and MMP‐9.

Conclusions

The aMMP‐8‐PoC test can be conveniently implemented to alert for and detect active collagenolysis affecting peri‐implant tissues, both in the early and advanced stages of the disease. Active and fragmented MMP‐8 exhibits a strong and significant association with peri‐implantitis as compared to total MMP‐8 and other biomarkers and can be utilized as the POC/chairside biomarker of choice in the new classification of peri‐implantitis.

Active matrix metalloproteinase-8 (aMMP-8) point-of-care test (POCT) in the COVID-19 pandemic

INTRODUCTION

Active matrix metalloproteinase (aMMP)-8 utilized in point-of-care testing (POCT) is regarded as a potential biomarker for periodontal and peri-implant diseases. Various host and microbial factors eventually influence the expression, degranulation, levels and activation of aMMP-8. The type of oral fluids (saliva, mouthrinse, gingival crevicular, and peri-implant sulcular fluids [GCF/PISF], respectively) affect the analysis.

AREAS COVERED

With this background, we aimed to review here the recent studies on practical, inexpensive, noninvasive and quantitative mouthrinse and GCF/PISF chair-side POCT lateral flow aMMP-8 immunoassays (PerioSafe and ImplantSafe/ORALyzer) and how they help to detect, predict, monitor the course, treatment and prevention of periodontitis and peri-implantitis. The correlations of aMMP-8 POCT to other independent and catalytic activity assays of MMP-8 are also addressed.

EXPERT OPINION

The mouthrinse aMMP-8 POCT can also detect prediabetes/diabetes and tissue destructive oral side-effects due to the head and neck cancers' radiotherapy. Chlorhexidine and doxycycline can inhibit collagenolytic human neutrophil and GCF aMMP-8. Furthermore, by a set of case-series we demonstrate the potential of mouthrinse aMMP-8 POCT to real-time/online detect periodontitis as a potential risk disease for coronavirus disease 2019 (COVID-19). The clinical interdisciplinary utilization of aMMP-8 POCT requires additional oral, medical, and interdisciplinary studies.

Comparing periodontitis biomarkers in saliva, oral rinse and gingival crevicular fluid: A pilot study

AIM

To explore the feasibility of screening for periodontitis by measuring biomarkers, namely total proteolytic activity (TPA), matrix metalloproteinase (MMP)-8, chitinase, lysozyme or their combination, in saliva, oral rinse and gingival crevicular fluid (GCF).

MATERIAL AND METHODS

Subjects were recruited among healthy/gingivitis individuals and untreated periodontitis patients in Academic Centre for Dentistry Amsterdam (ACTA). All participants donated samples of unstimulated whole saliva, oral rinse and GCF. The protein concentrations and MMP-8 levels were determined by ELISA. Enzymatic activities were measured using appropriate fluorogenic substrates.

RESULTS

In oral rinse samples, periodontitis patients (n = 19) exhibited significantly higher concentrations of MMP-8 and TPA than controls (n = 20). MMP-8 in combination with chitinase explained 88% of the variance and assigned a subject to control or periodontitis group, with best accuracy (87.2%) in oral rinse.

CONCLUSIONS

The combination of MMP-8 and chitinase in the current oral rinse procedure has the potential to discriminate periodontitis from periodontal health/gingivitis.

Diagnostic accuracy of a point-of-care aMMP-8 test in the discrimination of periodontal health and disease

Aim

To assess the diagnostic utility of an oral rinse active matrix metalloproteinase‐8 (aMMP‐8) point‐of‐care test (POCT) for differentiating periodontal health, gingivitis, as well as different stages and grades of periodontitis.

Materials & Methods

The aMMP‐8 index test was undertaken in 408 consecutive adults, followed by a full‐mouth periodontal examination. The reference standard was the 2017 World Workshop classification of periodontal diseases. Sensitivity, specificity, and the area under the receiver operating characteristic curve (AUROC) were assessed.

Results

68.6% of the participants were diagnosed with periodontitis, including Stages I (15.9%), II (15.9%), III (29.7%) and IV (7.1%). A positive aMMP‐8 POCT was associated with periodontitis after adjusting for age, gender, tobacco smoking and systemic diseases, while it was unable to differentiate among the stages/grades of periodontitis and between gingivitis/periodontal health. This test showed a sensitivity of 33.2% and a specificity of 93.0% for detecting periodontitis (threshold level >10 ng/ml). The levels of aMMP‐8 adjusted by the number of teeth present (aMMP‐8/NTP) performed better for periodontitis (sensitivity: 67.1%; specificity: 68.8%). Notably, aMMP‐8/NTP were strongly predictive for Stage IV periodontitis (threshold level =0.4312 ng/ml) (sensitivity: 89.7%; specificity: 73.6%; and AUROC: 0.856). The test performance greatly improved in combination with age and smoking, with a sensitivity of 82.5%, a specificity of 84.4%, and an AUROC of 0.883.

Conclusion

This aMMP‐8 POCT is able to detect periodontitis with better specificity than sensitivity across the spectrum of its severity. This test may be useful for periodontal screening in conjunction with subject characteristics and/or other sensitive screening tools. Further validation studies are needed.

Diagnostic ability of salivary matrix metalloproteinase-9 lateral flow test point-of-care test for periodontitis

AIM

This cross-sectional study aimed to examine the diagnostic ability of salivary matrix metalloproteinase (MMP)-9 lateral flow test (LFT) point-of-care (POC) kit and develop an algorithm for diagnosis of periodontitis.

MATERIALS AND METHODS

Through Seoul National Dental Hospital, 137 participants (46 LFT negatives, 91 LFT positives) were recruited. For salivary diagnostics, 150 μl of the unstimulated saliva was applied to LFT-POC kit. To make a diagnosis of periodontitis, stage II-IV in modified new international classification system was used. Covariates encompassing age, sex, smoking and obesity were evaluated through face-to-face interview. Enzyme-linked immunosorbent assay was used for quantification of salivary MMP-9. To develop a diagnostic algorithm, multivariable logistic regression analysis was used. Receiver operating characteristic curve was applied for evaluating diagnostic ability.

RESULTS

Diagnostic ability of salivary MMP-9 LFT-POC test was 0.82 (sensitivity of 0.92, specificity of 0.72) in total participants. Diagnostic algorithm using POC test resulted in a response equation, that is algorithm score = -3.675 + 2.877*LFT + 0.034*age + 0.121*sex + 0.372*smoking + 0.192*obesity. Diagnostic ability of the algorithm was 0.88 (sensitivity of 0.92, specificity of 0.85) with cut-off score of 0.589.

CONCLUSIONS

Salivary MMP-9 LFT-POC kit showed appropriate diagnostic ability for periodontitis and would be an efficient tool for screening of periodontitis.

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.

Prediabetes/diabetes screening strategy at the periodontal clinic

Objective

The aim of the study was to propose an efficient chairside clinical strategy for the identification of undiagnosed hyperglycaemia in periodontal clinics.

Material and methods

Α chairside system was used for assessment of glycated hemoglobin 1c (HbA1c) and active Matrix Metalloproteinase‐8 levels (aMMP‐8) were analyzed by immunotest in patients (n = 150) who fulfilled the criteria for screening of the Centers for Disease Control and Prevention. Full‐mouth periodontal parameters were assessed and various data such as Body Mass Index (BMI), smoking and education were recorded.

Results

Thirty‐one patients out of 150 tested were found with unknown hyperglycaemia (20.7%). Regarding sex, education, parent with diabetes, normal BMI, smoking, age ≥45 years and prior testing for diabetes, no differences were observed between subjects displaying HbA1c < 5.7 and ≥5.7% (Pearson's Chi‐square test, p > .05). Subgroups differed regarding BMI (kg/m²), tooth count, percentages of 4 and 5 mm pockets (Mann–Whitney and z‐test, p < .05). The diagnostic performance for HbA1c ≥5.7 was tested by Receiving Operator Characteristic curves and Areas Under the Curve (AUC) for the following: age ≥ 45 years and BMI (AUC 0.651, p = .010), the above and aMMP‐8 (AUC 0.660, p = .006), age ≥ 45 years, BMI and Stage of Periodontitis (AUC 0.711, p < .001) and age ≥ 45 years, BMI, aMMP‐8 and stage of periodontitis (AUC 0.713, p < .001).

Conclusions

Findings of the study suggest that the combination of stage of periodontitis, increasing age, BMI and aMMP‐8, without chairside HbA1c assessment appears to be a viable screening strategy for referring dental patients for testing for prediabetes/diabetes.

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.

Periodontal disease and targeted prevention using aMMP-8 point-of-care oral fluid analytics in the COVID-19 era

Periodontal disease is a chronic multifactorial infectious and inflammatory disease associated with several chronic systemic diseases, such as diabetes, cardiovascular diseases (CVD), chronic obstructive pulmonary disease, hypertension, Alzheimer’s disease and so on. These same systemic diseases have been associated with severe COVID-19 infections. Several recent studies have suggested hypotheses for the potential association between periodontal disease and severe COVID-19. Periodontal disease is also one of the most prevalent diseases globally. All this supports the importance of good oral health, also in the COVID-19 era. Thus, new strategies and approaches to identify patients at risk of periodontal disease could be beneficial to enhance secondary prevention, especially if targeted to COVID-19 risk groups. Diagnostic biomarkers for periodontal disease have been researched extensively. Potential biomarkers in oral fluid with currently available rapid non-invasive point-of-care technology, such as aMMP-8, could help to extend screening and identification of patients at risk for periodontal disease also to situations and places where professional dental expertise and equipment are limited or unavailable. i.e., nursing and care homes, and rural and distant places. The oral fluid point-of-care technologies could also be useful in the hands of medical professionals (diabetes, CVD, etc.) to identify patients at risk for undiagnosed periodontal disease and to refer them to a dentist for examination and evaluation. Finally, if there is a causality between periodontal disease and severe COVID-19 infections, these point-of-care oral fluid biomarker technologies could possibly also help in the assessment of the risk of deterioration and complications.

An Oral Rinse Active Matrix Metalloproteinase-8 Point-of-Care Immunotest May Be Less Accurate in Patients with Crohn's Disease

The diagnostic accuracy of point-of-care (PoC) applications may be compromised in individuals with additional inflammatory conditions. This cross-sectional study examined the performance of a commercial oral rinse active matrix metalloproteinase-8 (aMMP-8) PoC immunotest in individuals with (n = 47) and without Crohn's disease (CD) (n = 41). Oral rinse collected from the participants was analyzed by the PoC immunotest. Molecular forms and fragments of salivary MMP-8 were detected by western immunoblotting. The sensitivity of the immunotest for periodontitis was 60.0% in the CD group and 90.0% in the control group. The respective specificity was 75.0% and 80.0%. In both groups, clinical diagnosis of periodontitis exhibited a significant association with the immunotest results, however, the odds ratio (OR) was more than ten-fold in controls (OR 54.3, 95% CI: 3.1-953, p = 0.006) in comparison to CD patients (OR 5.2, 95% CI: 1.3-21.6, p = 0.022). According to Western immunoblot results, the immunotest MMP-8 positivity was not related to elevated levels of molecular forms and fragments of MMP-8 in the CD group, as in the control group. The diagnostic accuracy of the aMMP-8 PoC oral rinse immunotest is reduced in CD patients, which may be related to lower levels or undetectable complexes.

Active MMP-8 (aMMP-8) as a Grading and Staging Biomarker in the Periodontitis Classification

The aim of this study was to investigate the utility of incorporating active matrix metalloproteinase-8 (aMMP-8) as a biomarker into the new periodontitis classification system (stage/grade) presented in 2018. This study included 150 Greek adults aged 25-78, of whom 74 were men and 76 women. Participants were tested with an aMMP-8 point-of-care mouthrinse test, after which a full-mouth clinical examination was performed to assess their periodontal and oral health. The aMMP-8 levels in mouthrinse were significantly lower among healthy patients compared with patients in more severe periodontitis stages and grades (Kruskal-Wallis test and Dunn-Bonferroni test for pairwise post-hoc comparisons; p < 0.01 and p < 0.05, respectively). Furthermore, aMMP-8 levels were less correlated with plaque levels than bleeding on probing (BOP) (Spearman's rho = 0.269, p < 0.001; Spearman's rho = 0.586, p < 0.001); respectively). Thus, aMMP-8 was more robust to the confounding effects of oral hygiene than traditional periodontal parameter bleeding on probing. The aMMP-8 point-of-care mouthrinse test can be utilized as an adjunctive and preventive diagnostic tool to identify periodontal disease, classified by stage and grade, and ongoing periodontal breakdown chairside in clinical practice in only 5 min. Overall, integrating aMMP-8 into the new periodontitis classification system seems beneficial.

Antimicrobial and Anti-inflammatory Lingonberry Mouthwash - A Clinical Pilot Study in the Oral Cavity

Fermented lingonberry juice was designed to be used as a mouthwash. Our aim was to study the antimicrobial and anti-inflammatory effects of the mouthwash in the oral cavity. A clinical study of 30 adult participants was performed. A total of 20 participants used 10 mL of the mouthwash twice daily for two weeks and 10 participants used 20 mL twice daily for one week. Streptococcus mutans, Candida and Lactobacilli were cultivated at the beginning, after the mouthwash period and after a washout period. At the same timepoints an additional oral mouthrinse was collected for chair-side/point-of-care (POC)-PerioSafe^®/OraLyzer^® aMMP-8 quantitative on-line evaluation, and an oral clinical investigation was performed. Mean Streptococcus mutans and Candida counts, visible plaque index (VPI) and bleeding on probing (BOP) were reduced, and Lactobacilli counts increased during the lingonberry mouthwash period. The aMMP-8 mouthrinses showed reduced values in both test groups when compared to the startpoint. The mouthrinse aMMP-8 reduction correlated with the reductions in microbial counts, VPI and BOP. Based on the results, fermented lingonberry juice seems a promising aid in oral homecare, diminishing the microbial and related proinflammatory burden by balancing the oral microbial flora and gradually lowering the inflammatory load in the oral cavity.

Matrix metalloproteinases and inhibitors in dentistry

OBJECTIVES

Matrix metalloproteinase (MMP) expression has been associated with tissue development, invasive cancer cell behavior, and inflammation. The associations of increased expression of MMPs with diseases have led to intensive research activities to develop MMP inhibitors. Here, the questions are addressed which associations between increased levels of any MMP with dental diseases may be cause or consequence, whether MMP levels may be of diagnostic value and whether and which MMP inhibitors need further investigations for use in dental diseases.

METHODS

To study the role of MMPs and to discriminate between cause or consequence, the literature about measurements of MMPs and about the use of inhibitory drugs and genetic knockout animal models in dentistry was compared.

RESULTS

The only FDA-approved treatment with MMP inhibitors is tetracyclines for periodontitis, whereas a diagnostic test for activated MMP-8 in oral fluids is valued in practical periodontology. The MMP literature in dentistry is artificially skewed to the gelatinases MMP-2 and MMP-9 and to enamelysin, alias MMP-20. The basis for this observation is, respectively, the widely used and sensitive technique of gelatin zymography and enamel proteins as substrates of MMP-20. Studies on additional MMPs are gaining interest in dentistry and MMP inhibitors may provide new applications. In addition, drugs with proven effects for the treatment of dental diseases may be found to act through MMP inhibition.

CONCLUSION AND RELEVANCE

In conclusion, research on MMPs and inhibitors may provide practical applications beyond diagnosis and treatment of periodontitis and will be, directly or indirectly, beneficial for patients with dental or periodontal diseases.

Associations of chairside salivary aMMP-8 findings with periodontal parameters, potentially periodontal pathogenic bacteria and selected blood parameters in systemically healthy adults

The aim of this cross-sectional study was to investigate associations between salivary active matrix-metalloproteinase 8 (aMMP-8) and periodontitis severity, potentially periodontal pathogenic bacteria as well as blood parameters in generally healthy participants. Therefore, 188 participants with a mean age of 48.9 ± 8 years were examined. The periodontitis severity was assessed based on periodontal probing depth and clinical attachment loss. Both, aMMP-8 and microbiological analysis were performed using a validated, commercially available test system. Blood values were utilized from regular differential blood count. The aMMP-8 findings were associated with the periodontitis severity (P < 0.01), as well as with the prevalence of Porphyromonas gingivalis, Tannerella forsythia, Prevotella intermedia, Parvimonas micra, Camphylobacter rectus and Eubacterium nodatum (P_i < 0.05). No associations between aMMP-8 and the examined blood parameters were found (P_i > 0.05). In conclusion, salivary aMMP-8 findings seem to reflect periodontal disease severity as a result of an immunoreaction, especially against bacteria with high periodontal pathogenic potential.

Active Matrix Metalloproteinase-8 Point-of-Care (PoC)/Chairside Mouthrinse Test vs. Bleeding on Probing in Diagnosing Subclinical Periodontitis in Adolescents

This cross-sectional study compares the effectiveness of an active MMP-8 (aMMP-8) point-of-care (PoC)/chairside mouthrinse test to the conventional bleeding on probing (BOP) (cutoff 20%) test in detecting subclinical periodontitis/pre-periodontitis in Finnish adolescents. The study was carried out at the Kotka Health Center, Finland. A total of 47 adolescents (30 boys/17 girls) aged 15–17 were first tested with the aMMP-8 PoC test, followed by a full-mouth evaluation of clinical parameters of oral health including periodontal, oral mucosal, and caries assessment. A periodontist performed these clinical examinations. The aMMP-8 PoC test result had much stronger association with subclinical periodontitis than the BOP 20% test (2.8–5.3 times stronger in terms of odds ratio). The aMMP-8 PoC test had ≥2 times higher sensitivity than the BOP 20% test with, generally, the same specificity. Further, the aMMP-8 PoC test had generally better accuracy and lower false negative percentages. The aMMP-8 PoC test seemed to be more effective than the conventional BOP test in detecting subclinical periodontitis/pre-periodontitis in adolescents reducing the risk of their undertreatment. However, the sample size may be a limiting factor, and more studies are needed to confirm our results for both adolescents and adults.

Salivary S100 proteins screen periodontitis among Korean adults

AIM

This study aims to evaluate the association of salivary S100A8 and A9 proteins with periodontitis and its screening ability for periodontitis cross-sectionally.

MATERIAL AND METHODS

We selected 326 participants from the Yangpyeong Cohort: 218 participants with periodontitis and 108 participants without periodontitis. Stage II-IV periodontitis according to the modification of new international classification of periodontitis was considered as periodontitis. S100A8 and A9 were assayed using enzyme-linked immunosorbent assay kit. Age, sex, education, smoking, drinking, exercise, and metabolic syndrome were factored as confounders. Analyses of covariance and logistic regression analysis were applied to evaluate the association of S100A8 and A9 with periodontitis. Receiver operating characteristic curve was applied for screening ability.

RESULTS

Those with periodontitis compared to those without periodontitis showed higher adjusted amount of S100A8 (3694 versus 6757 ng/ml, p < 0.001), but less adjusted amount of S100A9 (1341 versus 1030 ng/ml, p = 0.015). The screening ability of S100A8 and A9 on periodontitis was c-statistics of 0.69 (p < 0.001) for both S100A8 and A9, 0.67 for S100A8 and 0.63 (p < 0.001) for S100A9.

CONCLUSIONS

Overall, salivary S100A8 and S100A9 could be practical markers for periodontitis. Its screening ability for periodontitis could be beneficial in clinics and at home.

Potential Application of Ixeris dentata in the Prevention and Treatment of Aging-Induced Dry Mouth

Dry mouth is a common complaint among the elderly population. The aim of this study was to investigate the effect of Ixeris dentata (IXD) extract on aging-induced dry mouth. We used young (two months) and aged (20 months) SD rats in our study. Using water as the vehicle, IXD extract (25, 50, and 100 mg/kg) was given via oral gavage to the young and aged rats for eight weeks. We found that the salivary flow rate relative to the submandibular gland weight was differently influenced by IXD extract treatment. IXD extract augmented the submandibular gland acinar cells, which are depleted during aging. In addition, the decreased salivary alpha-amylase, inositol triphosphate receptor, and aquaporin-5 in the aging rats were upregulated by IXD treatment. Free radical-induced oxidative stress in the aging rats was also alleviated in the IXD-treated group. The formation of high molecular weight complexes of protein disulfide isomerase, decreased expression of an ER chaperone (GRP78), and increased ER stress response (ATF-4, CHOP and p-JNK) in aging rats was regulated with IXD treatment, and eventually increased salivary secretions from the aging submandibular glands. These are the first data to suggest that IXD extract might ameliorate aging-associated oral dryness by regulating the ER environment.