Wissenschaft

Dentognostics entscheidet über die Entwicklung oder Aufnahme von Produkten in das Perio Präventions System nach wissenschaftlichen Kriterien und messbarem Kundennutzen für Behandler und Patienten. Für alle an der Wissenschaft Interessierten haben wir wissenschaftliche Literatur zu ausgewählten Themen zusammengefasst. Die Literatur ist überwiegend in Kurzfassung verfügbar. Wenn Sie wissenschaftlich Unterstützung benötigen oder selbst Studien mit aMMP-8 oder unsern Produkten planen, kontaktieren Sie uns bitte unter km@dento.de.

At dentognostics the decision if to develop or acquire a product or system and to bring it to the market with in its Perio Prevention System, is driven by science and performance for our customers, users and patients. To introduce those interested in the science behind we have assembled and collected scientific literature by topic. Most of the literature is available as abstracts. If you need further scientific support or if you plan to do studies with aMMP-8 or one of our products, please contact us at km@dento.de.

 

MMP-8

Fifty years ago research started on Matrix Metalloproteinases (MMPs; Woessner 2002), when Gross und Lapière (1962) tried to answer the question how the disappearance of tad-pole tissue during metamorphosis works. Regarding the scientific relevance the tadpole be-came a prince: „a tail of a frog that became a prince“ (Brinckerhoff and Matrisian 2002).

Matrix metalloproteinases are zinc-dependent enzymes which are involved in any destructive or remodeling processes of `matrix molecules´ like collagen or elastin. If overexpression of MMPs occurs due to an imbalance between MMPs and their inhibitors, the `Tissue Inhibitors of Metallo-Proteinases´ (TIMPs; Woessner 2002), quite a lot of pathologies may occur. A few representative examples are shown in the following table (adapted from Potempa et al. 2000):

Pathologic consequences of enhanced activity of MMPs (from Potempa et al. 2000)

Disease The cause of unregulated proteolytic activity
Rheumatoid arthritis Overexpression of matrix metalloproteinases
Glomerulonephritis Either enhanced expression of matrix metalloproteinases, or release of neutrophil serine proteinases
Septic shock Uncontrolled activation of the zymogens of coagulation and fibrinolysis cascades, and/or neutrophil degranulation
Tumor invasion and metastasis Excessive expression of matrix metalloproteinases
Periodontitis Release of large amounts of elastase and matrix metalloproteinases by neutrophils accumulating at the site of infection

 

MMP-8 and Periodontitis

For a selection of more then 160 scientific citations regarding Periodontal Disease and MMP-8 on PubMed see here.

Periodontitis is described as chronic inflammation culminating in the destruction of tissue and/or bone. Presented schematically and extremely simplified the inflammatory process proceeds as follows:

(1) Triggering stimulus

e.g. supra- or subgingival bacteria

(2) Release of bacterial mediators

mainly lipopolysaccharide (LPS)

(3) Attraction and activation of inflammatory cells

e.g. macrophages, polymorphonuclear granulocytes (PMN)

(4a) Release of tissue (autologous) mediators

such as prostaglandins and interleukins

(4b) Activation of matrix-metalloproteinases (MMPs)

i.e. of tissue-destroying collagenases

This process is controlled or inhibited by

(5a) Regulation of MMPs by “tissue inhibitors of metalloproteinases” (TIMPs)

(5b) Suppression of MMPs with sub-dose doxycycline (SDD, LDD)

(6) Periodontal therapy by removing the triggering stimulus (1), the bacterial biofilm.

These highly complex interrelationships are described in various review articles (e.g. Reynolds 1996, Page & Kornman 1997, Birkedahl-Hansen 1993, Birkedahl-Hansen 1998, Sorsa et al. 2014 (in press).

2.1 MMP-8: The oral matrix metalloproteinase in sulcus fluid

It is undisputed that MMP-8 represents the most important detectable matrix-metalloproteinase in gingival crevicular fluid (GCF) for periodontopathic processes (Birkedahl-Hansen 1998, Sorsa et al. 2006, Sorsa et al. 2014 in Press, and others), see corresponding citations from review articles:

Reynolds et al. 1994 ”members of the family of MMPs are key enzymes in matrix degradation”
Teronen et al. 1997 ”Of the known interstitial collagenases … MMP-8 is known to be predominant in the most common form of periodontal disease, adult periodontitis (AP)…”
Sorsa et al. 1999 ”MMPs, expecially collagenase-2  (MMP-8), are key mediators of irreversible tissue destruction associated with periodontitis and peri-implantitis. MMP8 is known to exist in elevated amounts and in active form in the gingival crevicular fluid (GCF) and peri-implant sulcular fluid (PISF) from progressing periodontitis and peri-implantitis lesions and sites, respectively.”
Kinane 2000 ”matrix metalloproteinase activity is associated with inflamma-tion related to both gingivitis and periodontitis.“
Sorsa et al. 2004 ”The role of collagenase, especially MMP-8, in periodontitis and peri-implantitis is the best-known example of the unwanted tissue destruction related to increased presence and activity of MMPs at the site of disease”

2.2 Different forms of matrix-metalloproteinases

MMP-8 is stored in sub-cellular, specific granules of mature human PMNs in peripheral blood (Hanemaaijer et al. 1997). The PMN leukocytes liberate their MMPs by granule release within seconds (Birkedahl-Hansen 1993). This means that these proteinases are available in an inactive pre-form and are very quickly activated on demand. In simplified terms, MMPs are actually available in 3 different forms (Nagase 1997, Palosaari 2003, Palosaari et al. 2003, Sorsa et al. 2004):

(a) in a latent, inactive pro-enzyme or zymogene form

(b) after cleavage of a C-terminal peptide in an active form,

(c) which is deactivated by TIMPs (inactive form).

Fine tuning of the tissue destruction is therefore dependent on the relationship of MMPs to TIMPs (Nomura et al.1998, Page et al.1997, Sorsa et al. 2014), which is described as a “delicate balance”. The MMPs may be enhanced due to the inflammatory processes in relation to the TIMPs already existing in the tissue. In this respect it should be noted that only the active form of the enzyme is of significance in periodontal tissue destruction. In order to detect this singularly important form of MMP-8 monoclonal antibodies have been produced (MoAbs 8708 and 8706; Hanemaaijer et al. 1997, Sorsa et al. 1999, Sorsa et. al. 2002), which recognize mainly the active collagenase.

Concerning this digest the active form of MMP-8 will be named aMMP-8.

2.3 aMMP-8 for Differentiation of patient groups in Periodontitis

During the last decade it was proven in several independent international publications that the quantitative site-specific assessment of aMMP-8 from GCF allows the researcher and the clinician to distinguish significantly between healthy sites, sites with gingivitis and those with periodontitis (Mäntylä et al. 2003, Prescher et al. 2007, Leppilahti et al. 2014, Sorsa et al 2014). Because, in detail, different technologies and calculation regimes where used by different research groups (Sorsa et al. 2010) the mere values of aMMP-8 from GCF are not always directly comparable.

Unequivocally, however, any of the corresponding studies has shown

  • Very low aMMP-8 values at healthy sites;
  • Slightly elevated, physiological aMMP-8 levels in case of gingivitis;
  • Strongly increased pathologic aMMP-8 values in cases of (untreated) periodontitis (Prescher et al. 2007), with quite high standard deviations (Mäntylä et al. 2003);
  • and a significant decline of aMMP-8 levels after periodontal therapy (cf. paragraph 4.)

2.4 Predictive value of aMMP-8

It should be noted that GCF-derived aMMP-8 levels possess a predictive value. Sorsa et al. (2010) presented a comparison of methods to assess MMP-8, mainly the ”immune-fluorometric assay” (IFMA) used in all investigations from the Sorsa group and with the dentognostics system (for examples see Munjal et al. 2007, Prescher et al. 2007, Kraft-Neumärker et al. 2012). In this context, periodontitis patients were examined over a course of 12 months at 2 month intervals. In these patients it was possible to clearly differentiate ”stable sites” from ”unstable sites”:

  • ”Stable sites“: Improvement in pocket depth (PD) and attachments (AL: attachment loss) were continuously preserved after treatment, similarly the aMMP-8 values were and remained consistently low;
  • ”Unstable sites“: No improvement or only temporary improvement in PD and AL were found, in parallel aMMP-8 only improved shortly after treatment, followed by an immediate re-increase in the aMMP-8 values.

Moreover Reinhardt et al. (2010) state, for example, that increases in MMP-8 during the first year of periodontal maintenance are associated with increased odds of subsequent periodontal attachment loss. Thus these authors conclude that elevated biomarkers of inflammation and bone resorption identify patients vulnerable to progressive periodontitis.

 

aMMP-8 in Peri-implant Sulcular Fluid (PISF) – Peri-Implantitis

For a selection of scientific citations regarding Periodontal Disease and MMP-8 on PubMed see here.

3.1 Assessing peri-implantitis and peri-implant mucositis
Ma et al. (2000) looked for collagenases (i.e. aMMP-8) in different categories of peri-implant vertical bone loss. According to the short table of results shown below, the authors summarize: „The loosening of dental implants is associated with vertical bone loss… we measured collagenase-2 (MMP-8) (MoABs 8706, 8708)… in PISF in 49 implant sites… Gingival Index did not correlate with the category of bone loss (p > 0.05). Collagenase-2 (was) higher (p < 0.05) in the group which had lost > 3 mm of bone than in the two other groups. Gingival Index is not a clinically important marker for bone loss, but collagenase-2 … in peri-implant sulcus fluid…”

Category Bone Loss < 1 mm 1-3 mm > 3 mm
GI 0.6 0.6 1.2
MMP-8 861 1265 2021

Another study conducted by Xu et al. (2008) clearly underlines the significance of the aMMP-8 biomarker in peri-implantitis (data from the results section and discussion from Xu et al. 2008):

Patient group Gingiva Index Pocket depth Bone loss* Collagenase activity (rel. units)
Healthy
Moderate periodontitis
Severe periodontitis
0.6
1.6
2.0
3.3
5.6
5.9
none
all
all
1
80
78
Healthy implant
Peri-implantitis
1.0
2.0
2.4
5.0
none
all
1
971

*Bone loss: Radiographically visible bone loss in none (healthy) or in all (periodontitis / peri-implantitis) for determination of collagenase activity selected sites.

The difference factor of 80 between “healthy” and “periodontitis” is in line with the spectrum of values as found in diverse research groups. In the case of peri-implantitis, a further spread by an additional factor of 10 times could be calculated. The authors draw the conclusion:
„… this study… is the basis for MMP-8 based… peri-implantitis diagnostics.“

3.2 Experimental peri-implant mucositis
The purpose of the investigation of Salvi et al. (2012) was to estimate the concentrations of MMP-8 in GCF of healthy teeth and corresponding PISF at healthy implants in the same 15 patients during the course of a so called “Experimental Gingivitis” (EG), i.e. a time of 21 days of neglected mechanical tooth brushing. Because peri-implant samples were also compared, this study is also an “Experimental Mucositis” (EM) investigation. Moreover the authors measured the concentrations of MMP-8 after reestablishment of the mechanical oral hygiene.

Outcome:

Day 0 7 14 21 28 35 42

EG

72 303 507 884 282 308 158

MG

438 988 1762 1678 476 948 822

Legend: EG: Experimental Gingivitis: No mechanical oral hygiene starting day 0 until day 21, thereafter restart of oral hygiene; MG: Experimental Mucositis analogous to EG. Values are medians of MMP-8 in pg / site.

  • At day 0 the MMP-8 values in healthy (!) PISF are much higher than in healthy GCF.
  • In both “groups” the MMP-8 values increase only due to non-brushing of 21 days. Thus MMP-8 monitors even this slight challenge accordingly.
  • In case of EG this increase is reversible (according to the definition of gingivitis / Experimental Gingivitis), what holds only partly true in the case of EM.

In sum, the investigations of Salvi et al. (2012) and Xu et al. (2008) compared GCF from teeth directly with PISF from implants. In any case, peri-implant mucositis or peri-implantitis, the implant-related MMP-8 values are markedly higher than these related to teeth/ periodontitis, whereas Gingivitis and peri-implant Mucositis if regarded clinically only do not seem to differ much (Lang NP, Bosshard 2011).

3.3 Peri-implantitis and peri-implant mucositis: relating MMP-8 and clinical findings

Generally it is very important to recognize these high concentrations of aMMP-8 in PISF as a tremendous challenge. It is to deduct therefrom that inflammatory peri-implant processes should run faster than those in periodontitis. In fact that is in line with clinical findings as reviewed and reported in the “Consensus of the 7th European Workshop on Periodontology” (Lang and Berglundh 2011, Berglundh et al. 2011), where the authors state that a `self-limiting´ process exists in the tissues around teeth, resulting in a protective capsule. However, such a `self-limiting´ does not occur in peri-implant tissues, so the lesions extend to the bony crest. It is claimed furthermore that peri-implant disease, in general, progress faster than periodontitis. The action of MMP-8 offers the physiologic explanation for the clinical outcome.

 

aMMP-8 concentrations during therapeutic measures – Reaction of the aMMP-8 concentration in GCF regarding therapy

SRP (Scaling / Root Planing) is the most frequently practiced method and the general first step in initiating periodontal therapy. Hence there are several studies relating the aMMP-8 concentration to the treatment outcome. Unequivocally it was proven in all of these studies that the levels of aMMP-8 drop significantly after therapy (Chen et al. 2000, Kinane et al. 2003, Mäntylä et al. 2003, Emingil et al. 2004; for review cf. Sorsa et al. 2014). For example Chen et al. (2000) found significant reductions in the MMP-8 per sample two weeks after SRP. MMP-8 and elastase activity correlated significantly. Significant correlations of both enzymes/activities existed with the clinical parameters GI (Gingiva Index) and BI (Bleeding Index), and partly with PD (pocket depth). As well, Kinane et al. (2003) established significant reductions in the MMP-8 concentrations (p < 0.005) 6-8 weeks after SRP. Following further periodontal therapy the MMP-8 values improved even more, after 3 months highly significant (p < 0.001) differences existed to the initial findings. Last not least Mäntylä et al. (2003) reported significant reductions in MMP-8 concentrations after SRP among periodontitis patients, including a sub-group with positive BOP. Thus the quantitative aMMP-8 diagnosis represents a strong tool to monitor any treatment effect.

 

aMMP-8 concentrations in saliva and/or mouth rinse samples

The ability to discriminate healthy subjects from patients with gingivitis / periodontitis holds also true for saliva specimen and / or mouth rinse samples. However, less work was done in this research area, and most of the studies deal with saliva (e.g., Gursoy et al. 2010, 2011, 2013, Salminen et al. 2014). Ramseier et al. (2009), assessing different biomarkers in saliva, stated that salivary MMP-8 is the most relevant biomarker concerning periodontitis. As well Leppilahti et al. (2011) used different methods to quantify aMMP-8 from mouth rinse samples. Moreover they calculated a Periodontal Inflammatory Burden Index (PIBI) to categorize the tested subjects. ROC analysis clearly showed that the aMMP-8 quantification differentiated the study group with strong periodontal inflammatory burden from those with lower levels.

Just recently Nwhator et al. (2014) used a qualitative lateral flow (LF) immunoassay (Perio Marker®, identical in construction with PerioSafe®PRO, dentognostics GmbH, Jena, Germany) containing MoABs 8708 and 8706 (as already described in section 1.4) to discriminate diverse patient groups. In strong accordance with Leppilahti et al. (2011) the LF point-of-care immunoassay differentiated patients from `good´, `fair´ and `poor´ oral hygiene categories. A 96 % sensitivity was established by these authors regarding poor oral hygiene, as well as a 95 % sensitivity for chronic periodontitis (defined as at least two sites per person with periodontal pockets). From both studies it is to conclude that mouth rinse samples could be used to reveal patients in risk for acute or further ongoing periodontitis.

 

Periodontal disease and Diabetes

For a selection of scientific citations regarding
Periodontal Disease and Diabetes on PubMed see here

 

Periodontal disease in gynecology and and reproductive medicine

Please refer to the following articles retrieved:

  1. Sanu O, Lamont RF. Periodontal disease and bacterial vaginosis as genetic and environment markers for the risk of spontaneous preterm labor and preterm birth. J Matern Fetal Neonatal Med. 2011; 24:1476-85.
  2. Zabor EC, Klebanoff M, Yu K, et al. Association between periodontal disease, bacterial vaginosis, and sexual risk behaviors. J Clin Periodontol. 2010;37(10):888-93.
  3. Kavoussi SK, West BT, Taylor GW, Lebovic DI. Periodontal disease and endometriosis: analysis of the National Health and Nutrition Examination Survey. Fertil Steril. 2009;91(2):335-42.
  4. Klinger A, Hain B, Yaffe H, Schonberger O. Periodontal status of males attending an in vitro fertilization clinic. J Clin Periodontol. 2011;38(6):542-6.
  5. Balakesavan P, Gokhale SR, Deshmukh V, Wiliams RC. Periodontal disease and overall health: An update. Eur J Gen Dent. 2013;2(2):102-8.
  6. Hart R. Periodontal disease: could this be a further factor leading to subfertility and is there a case for a pregnancy dental check-up? Womens Health. 2012;8(3):229-30.
  7. Hart R, Doherty DA, Pennell CE, et al. Periodontal disease: a potential modifiable risk factor limiting conception. Hum Reprod. 2012;27(5):1332-42.
  8. Xiong X, Elkind-Hirsch KE, Vastardis S, et al. Periodontal disease is associated with gestational diabetes mellitus: a case-control study. J Periodontol. 2009;80(11):1742-9.
  9. Contreras A, Herrera JA, Soto JE, et al. Periodontitis is associated with preeclampsia in pregnant women. J Periodontol. 2006;77(2):182-8.
  10. Augustin CA, Villar J, Lindheimer M. Maternal infection and risk of preeclampsia: systematic review and metaanalysis. Am J Obstet Gynecol. 2008;198(1):7-22.
  11. Xiong X, Buekens P, Fraser WD, Beck J, Offenbacher S. Periodontal disease and adverse pregnancy outcomes: a systematic review. BJOG 2006;113:135-143.
  12. Offenbacher S, Katz V, Fertik G, et al. Periodontal infection as a possible risk factor for preterm low birth weight. J Periodontol. 1996;67(10 Suppl):1103-13.
  13. López NJ, Smith PC, Gutierrez J. Higher risk of preterm birth and low birth weight in women with periodontal disease. J Dent Res. 2002;81(1):58-63.
  14. Dasanayake AP, Russel S, Boyd D, et al. Preterm low birth weight and periodontal disease among African Americans. Dent Clin North Am. 2003;47(1):115-25, x-xi.
  15. Madianos PN, Bobetsis GA, Kinane DF. Is periodontitis associated with an increased risk of coronary heart disease and preterm and/or low birth weight births? J Clin Periodontol. 2002;29 Suppl 3:22-38.
  16. Scannapieco FA, Bush RB, Paju S. Periodontal disease as a risk factor for adverse pregnancy outcomes. A systematic review. Ann Periodontol. 2003;8(1):70-8.
  17. Khader YS, Ta’ani Q. Periodontal diseases and the risk of preterm birth and low birth weight: a meta-analysis. J Periodontol. 2005;76(2):161-5.
  18. Offenbacher S, Jared HL, O’Reilly PG, et al. Potential pathogenic mechanisms of periodontitis associated pregnancy complications. Ann Periodontol. 1998;3(1):233-50.
  19. Radnai M, Gorzó I, Urbán E, et al: Possible association between mother’s periodontal status and preterm delivery. J Clin Periodontol. 2006; 33(11):791-6.
  20. Lopez NJ, Da Silva I, Ipinza J, Gutierrez J. Periodontal therapy reduces the rate of preterm low birth weight in women with pregnancy-associated gingivitis. J Periodontol. 2005; 76(11 Suppl):2144-53.
  21. Offenbacher S, Lin D, Strauss R, et al. Effects of periodontal therapy during pregnancy on periodontal status, biologic parameters and pregnancy outcomes: a pilot study. J Periodontol. 2006;77(12):2011-24.
  22. Deimling D, Kunze M, Ratka-Krüger P. Parodontale Erkrankungen während der Schwangerschaft. Gemeinsame Stellungnahme der Deutschen Gesellschaft für Parodontologie (DGP) und der Deutschen Gesellschaft für Zahn- Mund- und Kieferkrankheiten (DGZMK). Joing statement by the German Society for Periodontology (DGP) and the German Society of Dental, Oral and Craniomandibular Sciences, DGZMK).  Deutsche Zahnärztliche Zeitschrift 2007; 62(03)
  23. Zeng XT, Tu ML, Liu DY, et al. Periodontal disease and risk of chronic obstructive pulmonary disease: a meta-analysis of observational studies. PLoS One. 2012; 7(10): e46508.
  24. Mealey BL, Ocampo GL. Diabetes mellitus and periodontal disease. Periodontol 2000. 2007; 44:127-53.
  25. Bartold PM, Marshall RI, Haynes DR. Periodontitis and rheumatoid arthritis: a review. J Periodontol 2005; 76:2066-74.
  26. Ratka-Krüger P, Horodko M, Raetzke P. Parodontitis als möglicher Risikofaktor für untergewichtige Frühgeburten (Periodontitis as a possible risk factor for low-weight preterm infants). Risikokompendium Parodontitis (publisher: Quintessenz Berlin 2002, p. 85-95.
  27. Deimling D, Kunze M, Ratka-Krüger P. Parodontale Erkrankungen während der Schwangerschaft (Periodontal Diseases During Pregnancy). Gemeinsame Stellungnahme der  Deutschen Gesellschaft fürParodontologie (DGP) und der Deutschen Gesellschaft für Zahn- Mund- und Kieferkrankheiten (DGZMK). [Joint Statement by the German Society for Periodontology (DGP) and the German Society for Dental, Oral and Craniomandibular Disorders (DGZMK).] 62(03)
  28. Parks WC, Mecham RP. Matrix Metalloproteinases. San Diego: Academic Press, 1998.
  29. Mastragelopulos N, Haraszthy VI, Zambon JJ et al. Nachweis parodontal pathogener Mikroorganismen in atheromatösen Plaques (Evidence of periodontal pathogenic micro-organisms in atheromatic plaques). Der Chirurg 2002; 73: 585-591 Chirurg 2002; 73:585-91.
  30. Marcaccini AM, Novaes AB Jr, Meschiari CA, et al. Circulating matrix metalloproteinase-8 (MMP-8) and MMP-9 are increased in chronic periodontal disease and decrease after non-surgical periodontal therapy. Clin Chim Acta. 2009; 409(1-2):117-22.