International Poster Journal of Dentistry and Oral Medicine



Forgotten password?


Int Poster J Dent Oral Med 12 (2010), No. 3     15. Sep. 2010

Int Poster J Dent Oral Med 2010, Vol 12 No 3, Poster 495

Comparison of two different commercially available test kits to detect periodontal pathogens

Detection of periodontal pathogens

Language: English

Dr. Raluca Cosgarea, Dr. Amelie Bäumer, Nils Zimmermann, Prof. Dr. Dr. Ti-Sun Kim,
Section of Periodontology, Department of Operative Dentistry, University of Heidelberg

June 4-6, 2009
6th Congress of the European Federation of Periodontology
Stockholm, Sweden


This study compares two different test kits for detection and quantification of 4 periodontal pathogens in samples of subgingival plaque.

Material and Methods

69 Patients with aggressive or severe chronic periodontitis participated in this study. Microbiological analysis of pooled samples from subgingival plaque was performed with two different gene probe-tests [IAI Pado Test 4.5, Institut für Angewandte Immunologie, Zuchwill, Switzerland (PADO), and the Meridol Periodiagnostics, GABA, Lörrach, Germany (MERI)]. Agreement between the two protocols was calculated with kappa statistics for a categorical dichotomous diagnosis (positive/negative test result) and with a passing bablok regression (x= PADO, y=MERI) for the continuous data of bacterial counts in mio units.

Fig 1: Inserting sterile paperpoints in the periodontal pocket Fig 2: Taking plaque samples from the periodontal pockets
Fig 3: Collection of the plaque samples in transportation vials
Fig 4: Pooled plaque samples


Aggregatibacter actinomycetemcomitans (A.a.), Tannerella forsythia (T.f.), Porphyromonas gingivalis (P.g.) and Treponema denticola (T.d.) were identified with both PADO and MERI. For all 4 periodontal pathogens under examination, MERI tended to identify more patients with a positive diagnosis than PADO. Thus, the passing bablok regression equation revealed positive slopes for all 4 pathogens between 2.974 and 8.250. Kappa-statistics exhibited fair agreement for A.a (0.295), moderate agreement for T.f. and T.d. (0.509 and 0.576) and a good agreement for P.g. (0.689).

Fig 5: Detected percentual counts for 4 periopathogens with Pado and Meridol Test  
  A.a. P.g.
  Pado Meridol Pado Meridol
Patients tested positive [n] 13 17 50 54
Arithmetic mean [106] 0.09 0.37 3.75 14.18
Standard deviation [106] 0.13 0.87 3.29 16.18
Median [106] 0.02 0.07 3.47 9.90
Wilkoxon Test p > 0.05 p < 0.0001*
Tab 1: Difference in bacterial counts between Pado and Meridol
  T.f. T.d.
  Pado Meridol Pado Meridol
Patients tested positive [n] 63 66 63 64
Arithmetic mean [106] 2.98 6.91 1.27 7.30
Standard deviation [106] 2.42 10.42 1.19 4.60
Median [106] 2.30 3.80 1.11 4.60
Wilkoxon Test p < 0.0001* p < 0.0001*
Tab 2: Difference in bacterial counts between Pado and Meridol


Identification of periodontal pathogens may be inconsistent if different commercially available test kits are used.

This Poster was submitted by Dr. Raluca Cosgarea.

Correspondence address:
Dr. Raluca Cosgarea
University of Heidelberg
Department of Operative Dentistry, Section of Periodontology
Im Neuenheimer Feld 400
69120 Heidelberg