Nomenclature

Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans)

 Characteristics

Gram-negative, facultative anaerobes, 7 serotypes with different leukotoxin expression (serotype b with a high incidence of localised aggressive periodontitis)

 Pathogenicity

Highly pathogenic

 Virulence factors

Leukotoxin A
Chemotaxis inhibitory factor
Fibroblast inhibition
Bone-reabsorbing toxin
Collagenase
Lipopolysaccharide endotoxin

 Occurrence

In localised aggressive and chronic periodontitis. The virulence factors promote the colonisation and establishment of the germ in oro-pharyngeal space.

• Can be a trigger for rheumatoid arthritis

• Possible cause of endocarditis

 Treatment

Antibiotic of choice is amoxicillin
Cannot be safely eliminated with scaling / root planing

 Literature

Maeda, H., Fujimoto, C., Haruki, Y., Maeda, T., Kokeguchi, S., Petelin, M., Arai, H., Tanimoto, I., Nishimura, F. and Takashiba, S., 2003. Quantitative real-time PCR using TaqMan and SYBR Green for Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, tetQ gene and total bacteria. FEMMS Immunol Med Microbiol., 39 (1), 81-86.

Aberg, C.H., Kelk, P. and Johannsson, A., 2015. Aggregatibacter actinomycetemcomitans: virulence of its leukotoxin and association with aggressive periodontitis. Virulence, 6 (3), 188-195.

Malik, R., Changela, R., Krishan, P., Gugnani, S. and Bali, D., 2015. Virulence factors of Aggregatibacter actinomycetemcomitans – A status update. Journal of ICDRO, 7 (2), 137-145.

Nomenclature

Filifactor alocis

Characteristics

Gram-positive, extremely difficult to cultivate anaerobes

Pathogenicity

Highly pathogenic

Virulence factors

15 different proteases, Microbial Surface Components Recognizing Adhesive Matrix (MSCRAMMs), F. Alocis Complement Inhibitor (FACIN)

Occurrence

Occurs in subgingival specimens in chronic periodontitis (CP) and generalised aggressive periodontitis (GAP) and is associated with supportive tissue loss. Fa is the cause of chronic inflammation and induces the production of proinflammatory cytokines that lead to the apoptosis of gingival epithelial cells. Compared with Pg, Td, Tf, described in the literature as "red complex" and which are most commonly associated with periodontal disease in the literature, Fa was the third largest in a group of GAP patients and the second largest in CP patients. Fa is found predominantly in the biofilm region, originating from the middle or the apical part of the pocket (Schlafer, 2014).

Fa is always closely intertwined with other periodontal germs, and has a symbiotic relationship with Pg, for example, which may result in a structural increase in biofilm.

Treatment

Antibiotic of choice: Metronidazol

Literature

Aruni, A.W., Roy, F. and Fletcher, H.M., 2011. Filifactro alocis Has Virulence Attributes That can Enhance Ist Persistence under Oxidative Stress Conditions and Mediate Invasion of Epithelial Cells by Porphyromonas gingivalis. Infection and Immunity, 79 (10), 3872-3886.

Aruni, W., Chioma, O. and Fletcher, H.M., 2014. Filifactor alocis: The Newly Discovered Kid on the Block with Special Talents. Journal of Dental Research, 93 (8), 725-732.

Schlafer, S., 2014. Filifactor alocis-der noch unterschätze Parodontitis-Keim in der Zahnfleisch-tasche. [Filifactor alocis-the still underestimated periodontitis germ in gingival pockets]. Zahnmedizin Report, 9:3.
Aruni, W., Mishra, A., Dou, Y., Chioma, O., Hamilton, B.N. and Fletcher, H.M., 2015. Filifactor alocis- a new emerging periodontal pathogen. Microbes and Infection, 17 (7), 517-530.

Jusko, M., Miedzak, B., Ermert,D., Magda, M., King, B.C., Bielecka, E., Riesbeck, K., Eick, S., Potempa, J. and Blom, A.M., 2016. FACIN, a Double-Edged Sword of the Emerging Periodontal Pathogen Filifactor alocis: A Metabolic Enzyme Moonlighting as a Complement Inhibitor. Journal of Immunology, 197, 3245-3259.

Nomenclature

Porphyromonas gingivalis

Characteristics

Gram-negative strict anaerobe

Pathogenicity

Highly pathogenic

Virulence factors

Membrane-associated proteases, which, for example, split fibrinogen, which leads to bleeding on probing (BOP), releases haemin and iron and at the same time leads to further propagation of the germ as a food source. Lipopolysaccharides, exopolysaccharides, OMP (outer membrane proteins), collagenase, trypsin-like protease, gelatinase, aminopeptidase.

Occurrence

The germ does not belong to the "normal" oral flora; the immune system is unable to completely control an infection. It occupies the periodontal area more uniformly than A. actinomycemtemcomitans, which is more likely to occur in isolated areas.

Treatment

Can usually be removed with root planing. If it is nevertheless detected after this treatment, reintervention with curettage or surgery is indicated. If Pg and Aa are present in larger quantities, antibiotics must be prescribed in addition to scaling/root planing. Antibiotics of choice are metronidazole or ornidazole + amoxicillin.

Literature

Lyons, S.R., Griffen, A.L. and Leys, E.J., 2000. Quantitative Real-Time PCR for Porphyromonas gingivalis and Total Bacteria. Journal of Clinical Microbiology, 38 (6), 2362-2365.

Mysak, J., Podzimek, S., Sommerova, P., Lyuya-Mi, Y., Bartova, J., Janatova, T., Prochazkova, J. and Duskova, Jana, 2014. Porphyromonas gingivalis: Major Periodontopathic Pathogen Overview. Journal of Immunology Research, ID 476068, 8.

How, K.Y., Song, K.P.and Chan, K.G., 2016. Phorphyromonas gingivalis: An Overview of Periodontopathic Pathogen below the Gum Line. Frontiers in Microbiology, 7 (53).

Nomenclature

Prevotella intermedia

Characteristics

Gram-negative obligate anaerobes

Pathogenicity

Strongly pathogenic

Virulence factors

Exopolysaccharides (EPS)
Cystein Protease (Interpain A)

Occurrence

It has been documented as a (co-) pathogen of mostly mixed-infection dentoalveolar infections. It is also referred to as an early marker germ, which creates the anaerobic environment necessary for the settlement of the main periodontal germs via the metabolism of residual sugar in the sulcus or in the forming periodontal pocket. Pi uses steroid hormones as growth factors, and therefore occurs more often in pregnant women.

Treatment

Pi with increased germ counts can not be treated by means of scaling/root planing. Nitromidazole preparations (e.g. metronidazole) are the antibiotics of choice. Isolated penicillinase-related penicillin resistance is known; Other than anaerobic beta-lactam antibiotics (e.g, penicillin G, ampicillin, amoxicillin). The efficacy of clindamycin (resistance) and tetracycline varies; Aminoglycosides are always ineffective.

Literature

Riggio, M.P., Lennon, A. and Roy, K.M., 1998. Detection of Prevotella intermedia in subgingival plaque of adult periodontitis patients by polymerase chain reaction. Journal Periodontal Research, 33 (6), 369-376.

Potempa, M., Potempa, J., Kantyka, T., Nguyen, KA., Wawrzonek, K., Manadhar, S.P., Popadiak, K., Riesbeck, K., Eick, S. and Blom, A.M., 2009. Interpain A, a Cysteine Protease from Prevotella intermedia, Inhibits Complement by Degrading Complement Factor 3. PLoS Pathogens, 5 (2), e1000316.

Yamanaka, T., Yamane, K., Furukawa, T., Matsumoto-Mashimo, C., Sigimori, C., Obata, N., Walker, C.B., Leung, K.P. and Fukushima, H., 2011. Comparision of the virulence of exopolysaccharide- producing Prevotella intermedia to exopolysaccharide non- producing perodontoipathic organism. BMC Infection Disease, 11, 228-237

Nomenclature

Tannerella forsythia

Characteristics

Gram-negative strict anaerobe

Pathogenicity

Highly pathogenic

Virulence factors

3 proteolytic enzymes: Cysteine protease (PrtH), karilysin (structurally similar to human matrix metalloproteases), mirolase (calcium dependent serine protease)

Occurrence

Characteristically occurs with strong bone defects. In significantly higher numbers in "active" pockets than in "inactive" pockets. Also known in cases of recurrent periodontal disease. Often associated with refractory periodontids. There is a close relationship of coexistence with Treponema denticola and Porphyromonas gingivalis.

Treatment

Can usually be removed with root planing. Metronidazole or ornidazole are considered the antibiotics of choice, especially in cases of severe inflammatory symptoms.

Literature

Sharma, A., 2000. Virulence mechansims of Tannerella forsythia. Periodontology, 54 (1), 106-116.

Saito, D., Coutinho, L.L., Borges Saito, C.P., Tsai, S.M., Höfling, J.F. and Goncalves, R.B., 2009. Real-time polymerase chain reactionquantification of Porphyromonas gingivalis and Tannerella forsythia in primary endodontic infections. Journal of Endodontics, 35 (11), 1518-1524.

Ksiazek, M., Mizgalska, D., Eick, S., Thorgersen, I.B., Enghild, J.J. and Potempa, J. 2015. KLIKK proteases of Tannerella forsythia: putative virulence factors with a unique domain structure. Frontiers in Microbiology, 6, 312.

Nomenclature

Treponema denticola

Characteristics

Short, strictly anaerobic gram-negative spirochaete

Pathogenicity

Strongly pathogenic

Virulence factors

Tissue-destroying proteases, hyaluronidases, phosphatases and phospholipases. Stimulates formation of IL-1 alpha and TNF-alpha.

Occurrence

Is associated with periodontal destruction (advanced periodontitis), necrotising ulcerative gingivitis/periodontitis.

Treatment

It is useful as a marker in the evaluation of treatment success (scaling/root planing) in therapy refractory pockets. Antibiotics of choice, if necessary, are metronidazole or ornidazole.

Literature

Sela, M.N., 2001. Role of Treponema denticola in periodontal diseases. Crit Rev Oral Biol Med, 12 (5), 399-413.

Asai, Y., Jinno, T., Igarashi, H., Ohyama, Y. and Ogawa, T., 2002. Detection and Quantification of Oral Treponemes in Subgingival Plaque by Real-Time PCR. Journal of Clinical Microbiology, 40 (9), 3334-3340.

Dashper, S.G., Seers, C.A., Tan, K.H. and Reynolds, E.C., 2011. Virulence Factros of the Oral Spirochete Treponema denticola. Journal Dent. Research, 90 (6), 691-703.

Pandit, N., Gugnani, S., Sushil, D. and Bali, D., 2016. Treponema denticola:
A teammate in periodontal progression. Journal of ICDRO, 8 (1), 58-62.