Konietschke, Frank
Permanent URI for this collectionhttps://hdl.handle.net/10735.1/4450
Frank Konietschke is an Assistant Professor of Mathematical Sciences. His areas of expertise include:
- Nonparametric statistics
- Ranking procedures in factorial designs
- Multiple testing problems
- Resampling techniques
- Biostatistics
Browse
Recent Submissions
Item Intra- and Interobserver Reliability of Glenoid Fracture Classifications by Ideberg, Euler and AO(BioMed Central Ltd) Gilbert, F.; Eden, L.; Meffert, R.; Konietschke, Frank; Lotz, J.; Bauer, L.; Staab, W.; 0000 0000 7705 0437 (Konietschke, F); 107132211 (Konietschke, F); Konietschke, FrankBackground: Representing 3%-5% of shoulder girdle injuries scapula fractures are rare. Furthermore, approximately 1% of scapula fractures are intraarticularfractures of the glenoid fossa. Because of uncertain fracture morphology and limited experience, the treatment of glenoid fossa fractures is difficult. The glenoid fracture classification by Ideberg (1984) and Euler (1996) is still commonly used in literature. In 2013 a new glenoid fracture classification was introduced by the AO. The purpose of this study was to examine the new AO classification in clinical practice in comparison with the classifications by Ideberg and Euler. Methods: In total CT images of 84 patients with glenoid fossa fractures from 2005 to 2018 were included. Parasagittal, paracoronary and axial reconstructions were examined according to the classifications of Ideberg, Euler and the AO by 3 investigators (orthopedic surgeon, radiologist, student of medicine) at three individual time settings. Inter-and intraobserver reliability of the three classification systems were ascertained by computing Interand Intraclass (ICCs) correlation coefficients using Spearman's rank correlation coefficient, 95%-confidence intervals as well as F-tests for correlation coefficients. Results: Inter-and intraobserver reliability for the AO classification showed a perspicuous coherence (R = 0.74 and R = 0.79). Low to moderate intraobserver reliability for Ideberg (R = 0.46) and Euler classification (R = 0.41) was found. Furthermore, data show a low Interobserver reliability for both Ideberg and Euler classification (R <; 0.2). Both the Inter-and Intraclass reliability using AO is significantly higher than those using Ideberg and Euler (p < 0.05). Using the new AO classification, it was possible to find a proper class for every glenoid fossa fracture. On average, according to Euler classification 10 of 84 fractures were not classifiable whereas to Ideberg classification 21 of 84 fractures were not classifiable. Conclusion: The new AO classification system introduced 2013 facilitates reliable grading of glenoid fossa fractures with high inter-and intraobserver reliability in 84 patients using CT images. It should possibly be applied in order to enable a valid, reliable and consistent academic description of glenoid fossa fractures. The established classifications by Euler and Ideberg are not capable of providing a similar reliability.Item Effect of Fiber Insertion Depth on Antibacterial Efficacy of Photodynamic Therapy against Enterococcus Faecalis in Root Canals(Springer Berlin Heidelberg, 2018-09-24) Roedig, Tina; Endres, Sarah; Konietschke, Frank; Zimmermann, Ortrud; Sydow, Hans Georg; Wiegand, Annette; 107132211 (Konietschke, F); Konietschke, FrankThis in vitro study evaluated the effect of fiber insertion depth on antimicrobial efficacy of antimicrobial photodynamic therapy (aPDT) using a photosensitizer (PS; toluidine blue) and a red light-emitting diode (LED) in root canals infected with Enterococcus faecalis. Single-rooted extracted teeth were prepared with nickel-titanium-instruments, sterilized, contaminated with E. faecalis, and incubated for 72 h. Roots were randomly divided into four experimental groups: PS only, LED only, aPDT with LED in the apical third, aPDT with LED in the coronal third, as well as into infection and sterile controls (each n = 10). Samples were taken by collecting standardized dentine shavings from the root canal walls. After serial dilution and culturing on blood agar, colony-forming units (CFU) were counted. Both aPDT groups showed a CFU reduction of 1-2 log(10) steps compared with the infection control, whereas the effect of fiber insertion depth was negligible (< 0.5 log(10) steps). CFU reduction of approximately 0.5 log(10) steps for PS alone was detected compared with the infection control, but PS alone was less effective than both aPDT groups. No antibacterial effect was detected for LED alone. aPDT reduced E. faecalis within the root canal, whereas fiber insertion depth had a negligible influence on antimicrobial effectiveness of aPDT. The insertion depth of the light-emitting diode may not influence the antibacterial efficacy of photodynamic therapy against E. faecalis in straight root canals.