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959 Publications visible to you, out of a total of 959
Biomechanical properties of polymer-infiltrated ceramic crowns on one-piece zirconia implants after long-term chewing simulation
Genetical Statistics and Systems Biology

Abstract (Expand)

BACKGROUND Implant and superstructure provide a complex system, which has to withstand oral conditions. Concerning the brittleness of many ceramics, fractures are a greatly feared issue. Therefore, …, polymer-infiltrated ceramic networks (PICNs) were developed. Because of its low Young’s modulus and high elastic modulus, the PICN crown on a one-piece zirconia implant might absorb forces to prevent the system from fracturing in order to sustain oral forces. Recommendations for the material of superstructure on zirconia implants are lacking, and only one study investigates PICN crowns on these types of implants. Accordingly, this study aimed to examine PICN crowns on one-piece zirconia implants regarding bond strength and surface wear after long-term chewing simulation (CS). METHODS Twenty-five hybrid ceramic crowns (Vita Enamic, Vita Zahnfabrik) were produced using computer-aided design/computer-aided manufacturing (CAD/CAM) technology and adhesively bonded (RelyX™ Ultimate, 3M ESPE) to zirconia implants. Twenty of the specimens underwent simultaneous mechanical loading and thermocycling simulating a 5-year clinical situation (SD Mechatronik GmbH). Wear depth and wear volume, based on X-ray micro-computed tomography volume scans (Skyscan 1172-100-50, Bruker) before and after CS, were evaluated. All crowns were removed from the implants using a universal testing machine (Z010, Zwick GmbH&Co.KG). Subsequently, luting agent was light microscopically localized (Stemi 2000-C, Zeiss). With a scanning electron microscope (SEM, Phenom™ G2 pro, Phenom World), the area of abrasion was assessed. RESULTS 1. After CS, none of the tested crowns were fractured or loosened. 2. The maximum vertical wear after CS was M = 0.31 \pm 0.04 mm (mean \pm standard deviation), and the surface wear was M = 0.74 \pm 0.23 mm3. 3. The pull-off tests revealed a 1.8 times higher bond strength of the control group compared to the experimental group (t(23) = 8.69, p \textless 0.001). 4. Luting agent was mostly located in the crowns, not on the implants. 5. The area of abrasion showed avulsion and a rough surface. CONCLUSIONS PICN on one-piece zirconia implants showed high bond strength and high wear after CS.

Authors: Pia Baumgart, Holger Kirsten, Rainer Haak, Constanze Olms

Date Published: 1st Dec 2018

Publication Type: Journal article

Intra-individual alterations of serum markers routinely used in forensic pathology depending on increasing post-mortem interval
Genetical Statistics and Systems Biology

Abstract (Expand)

Post-mortem biochemistry of serum markers has been the subject of numerous studies, but in-situ marker stability after death has not been sufficiently evaluated yet. Such laboratory analyses are … especially necessary in the cases of functional deaths without morphological evidence of the death causes and also in cardiac death cases with only very short survival times. The aim of the study was to determine the post-mortem stability of commonly-used serum markers at predefined time points. In 20 cases, peripheral venous samples were taken starting immediately after circulatory arrest and ending 48 hours after death. Serum creatinine, urea, 3-\textgreekb-hydroxybutyrate, tryptase, myoglobin, troponin T, creatin kinase and creatin kinase-MB have been included. For all markers, we observed increasing marker levels for longer post-mortem intervals. Significant marker level changes began two hours after death. Excessive increases were observed for cardiac and muscle markers. Marker levels showed high intra-assay precision. Furthermore, the markers were robust enough to withstand freeze-thaw cycles. Potential contamination of arteriovenous blood did not influence the post-mortem marker levels. Post-mortem blood should be sampled as soon as possible, as increased post-mortem intervals may heavily change marker levels in-situ in individual cases, whereas the markers are mostly unaffected by laboratory conditions.

Authors: Lina Woydt, Michael Bernhard, Holger Kirsten, Ralph Burkhardt, Niels Hammer, André Gries, Jan Dreßler, Benjamin Ondruschka

Date Published: 1st Dec 2018

Publication Type: Journal article

Olfactory dysfunction: properties of the Sniffin' Sticks Screening 12 test and associations with quality of life.
LIFE Adult

Abstract (Expand)

PURPOSE: The Sniffin' Sticks Screening 12 test is a test of olfactory performance based on pen-like odor dispensing devices. The aims of this study were to analyze the performance of this test in … a general population sample and to explore associations between olfactory dysfunction and quality of life. METHODS: A large community sample (n = 7267) completed the Sniffin' Sticks Screening 12 test and several questionnaires measuring quality of life, anxiety, dispositional optimism, social support, and satisfaction with life. RESULTS: According to the criteria recommended by the test manufacturer, 5.1% of the participants were anosmic (score </= 6), 52.4% were dysosmic (7 </= score </= 10), and 42.5% were normosmic (score >/= 11). While frequencies of correct identification differed between the 12 sticks, all sticks contributed positively to the test results. The associations between olfactory functioning and quality of life variables were negligible. In the multivariate analyses, none of the associations reached the 1% significance level. CONCLUSIONS: While studies with patients in otorhinolaryngological clinics often report substantial detriments to their quality of life in relation to olfactory dysfunction, the present epidemiological study cannot confirm this association for the general population.

Authors: A. Hinz, T. Luck, S. G. Riedel-Heller, P. Y. Herzberg, C. Rolffs, K. Wirkner, C. Engel

Date Published: 21st Nov 2018

Publication Type: Not specified

Commentary: Arguing for Adaptive Clinical Trials in Sepsis.
SMITH - Smart Medical Information Technology for Healthcare

Abstract

Not specified

Authors: M. Kesselmeier, A. Scherag

Date Published: 15th Nov 2018

Publication Type: Journal article

Parameters of pulse wave velocity: determinants and reference values assessed in the population-based study LIFE-Adult
Genetical Statistics and Systems Biology

Abstract (Expand)

AIMS AND BACKGROUND Parameters of arterial stiffness such as pulse wave velocity (PWV) were recently proposed as independent risk factors of cardiovascular events. We analyse three PWV parameters in …n the large population-based study LIFE-Adult to identify risk factors, normal and reference values. METHODS AND RESULTS Brachial-ankle (ba), brachial-femoral (bf) and carotid-femoral (cf) PWV assessment was performed using Vicorder device. 8509 participants aged 19-80 were analysed. PWV parameters were moderately correlated (r(ba/bf) = 0.6, r(ba/cf) = 0.46, r(bf/cf) = 0.59). Age and blood pressure are the dominant determinants of PWV parameters explaining \textgreater 18% of variability. Sex was only relevant for bfPWV and cfPWV. All further analysed cardiovascular and other risk factors are of minor importance. We provide age-dependent percentiles for the population (reference values) and for the subgroup of normotonic individuals. All percentiles show a strong increase with age. The difference between normotonic and all individuals is small for younger age groups but increases up to 1 m/s for elderly subjects. CONCLUSION Our study confirms and further underpins the strong impact of age and blood pressure on arterial stiffness and the relatively weak contribution of other factors, supporting an independent role of arterial stiffness in cardiovascular disease development. Age-dependent reference and normal values were provided on the basis of the so far largest study sample facilitating the implementation of PWV assessment in clinical practice. Due to better compliance, handling and stronger association with age and blood pressure, baPWV could serve as an alternative to cfPWV. Follow-up data are required to estimate the clinical significance of specified PWV cut-offs.

Authors: Daniel Baier, Andrej Teren, Kerstin Wirkner, Markus Loeffler, Markus Scholz

Date Published: 1st Nov 2018

Publication Type: Journal article

Commentary: Arguing for Adaptive Clinical Trials in Sepsis
SMITH - Smart Medical Information Technology for Healthcare

Abstract

Not specified

Authors: Miriam Kesselmeier, André Scherag

Date Published: 30th Oct 2018

Publication Type: Journal article

Human Diseases: disease by infectious agent

The Influence of Number and Timing of Pregnancies on Breast Cancer Risk for Women With BRCA1 or BRCA2 Mutations
GC-HBOC - German Consortium for Hereditary Breast and Ovarian Cancer

Abstract (Expand)

Background Full-term pregnancy (FTP) is associated with a reduced breast cancer (BC) risk over time, but women are at increased BC risk in the immediate years following an FTP. No large prospective …e studies, however, have examined whether the number and timing of pregnancies are associated with BC risk for BRCA1 and BRCA2 mutation carriers. Methods Using weighted and time-varying Cox proportional hazards models, we investigated whether reproductive events are associated with BC risk for mutation carriers using a retrospective cohort (5707 BRCA1 and 3525 BRCA2 mutation carriers) and a prospective cohort (2276 BRCA1 and 1610 BRCA2 mutation carriers), separately for each cohort and the combined prospective and retrospective cohort. Results For BRCA1 mutation carriers, there was no overall association with parity compared with nulliparity (combined hazard ratio [HRc] = 0.99, 95% confidence interval [CI] = 0.83 to 1.18). Relative to being uniparous, an increased number of FTPs was associated with decreased BC risk (HRc = 0.79, 95% CI = 0.69 to 0.91; HRc = 0.70, 95% CI = 0.59 to 0.82; HRc = 0.50, 95% CI = 0.40 to 0.63, for 2, 3, and \geq4 FTPs, respectively, Ptrend \textless .0001) and increasing duration of breastfeeding was associated with decreased BC risk (combined cohort Ptrend = .0003). Relative to being nulliparous, uniparous BRCA1 mutation carriers were at increased BC risk in the prospective analysis (prospective hazard ration [HRp] = 1.69, 95% CI = 1.09 to 2.62). For BRCA2 mutation carriers, being parous was associated with a 30% increase in BC risk (HRc = 1.33, 95% CI = 1.05 to 1.69), and there was no apparent decrease in risk associated with multiparity except for having at least 4 FTPs vs. 1 FTP (HRc = 0.72, 95% CI = 0.54 to 0.98). Conclusions These findings suggest differential associations with parity between BRCA1 and BRCA2 mutation carriers with higher risk for uniparous BRCA1 carriers and parous BRCA2 carriers.

Authors: Mary Beth Terry, Yuyan Liao, Karin Kast, Antonis C. Antoniou, Jasmine A. McDonald, Thea M. Mooij, Christoph Engel, Catherine Nogues, Bruno Buecher, Véronique Mari, Jessica Moretta-Serra, Laurence Gladieff, Elisabeth Luporsi, Daniel Barrowdale, Debra Frost, Alex Henderson, Carole Brewer, D. Gareth Evans, Diana Eccles, Jackie Cook, Kai-Ren Ong, Louise Izatt, Munaza Ahmed, Patrick J. Morrison, Charlotte J. Dommering, Jan C. Oosterwijk, Margreet G. E. M. Ausems, Mieke Kriege, Saundra S. Buys, Irene L. Andrulis, Esther M. John, Mary Daly, Michael Friedlander, Sue Anne McLachlan, Ana Osorio, Trinidad Caldes, Anna Jakubowska, Jacques Simard, Christian F. Singer, Yen Tan, Edith Olah, Marie Navratilova, Lenka Foretova, Anne-Marie Gerdes, Marie-José Roos-Blom, Brita Arver, Håkan Olsson, Rita K. Schmutzler, John L. Hopper, Flora E. van Leeuwen, David Goldgar, Roger L. Milne, Douglas F. Easton, Matti A. Rookus, Nadine Andrieu

Date Published: 1st Oct 2018

Publication Type: Journal article

Human Diseases: hereditary breast ovarian cancer syndrome

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