Objective: Matrix metallo-proteinases play a key role in the pathogenesis of periodontitis. Specifically, active MMP-8 (aMMP-8) concentrations increase during degradation of collagenic fibers. Therefore, it was the aim of this investigation to obtain a full-mouth profile of active MMP-8 in untreated chronic periodontitis patients and to investigate the association between these biomarker values, pocket depths, bleeding and plaque. Method: In this mono-center cross-sectional study, 10 male patients who had untreated chronic periodontitis were included. Sulcus fluid was gathered at four sites of every tooth. After air drying, paper strips were inserted 2 mm into the sulcus, remained there for 30 s and were stored in tubes at -20°C. In the laboratory, aMMP-8 was extracted, linked to antibodies, and dyed. Active MMP-8 concentration was measured via optical density. Probing depths, bleeding on probing, plaque and gingival indices were documented at the same sites as aMMP-8 samples were taken. Descriptive statistics and multiple linear regression analyses for the prediction of PD or aMMP-8, espectively, were performed. Results: Participants were on average 47.1 years old (range 31-67). Mean aMMP-8 concentrations per patient ranged from .69 to 29.03ng/ml. Only one patient had a concentration lower than 10 ng/ml and four patients had values higher than 24ng/ml. Three of the four patients who had the highest aMMP-8 concentrations were smokers. Standard deviations were high between patients and within the dentition of a patient. Mean pocket depths ranged between 3.56 and 5.01mm, mean BOP between 42% and 89%. Plaque index varied between 0.81 and 1.82, gingival index between 1.25 and 1.60. The multiple regression analysis did not reveal statistically significant predictions for neither PD nor aMMP-8. Conclusion: Considerable intraindividual and interindividual differences concerning aMMP-8 values existed in this sample of male periodontitis patients. No relationship between aMMP-8 and PD was proven. Schlagwörter: matrix metalloproteinase 8, periodontitis, biomarker, pocket depth