Water sorption, water solubility, degree of conversion, elastic indentation modulus, edge chipping resistance and flexural strength of 3D-printed denture base resins.

OBJECTIVES: To investigate the water sorption (wsp), water solubility (wsl), degree of conversion (DC), elastic indentation modulus (EIT), edge chipping resistance (ECR) and flexural strength (FS) of 3D-printed, milled and conventionally polymerized denture base resin materials. METHODS: Specimens (N = 540) were 3D-printed (NextDent Denture 3D+ (DEN), Fotodent Denture (FOT), Freeprint Denture (FRE), V-Print dentbase (VPR)), cut (Ivotion Base (IVO)) and molded (PalaXpress (PAL)) in three geometries. Wsp,wsl,DC, EIT, ECR and FS were tested initially (24 h, 37 °C, H20) and after additional aging (5000 thermal cycles, 5/55 °C). Data were analyzed with Kolmogorov-Smirnov, univariate ANOVA, Kruskal-Wallis, Mann-Whitney U test and Spearman's correlation (p < 0.05) RESULTS: Most 3D-printed denture base resins showed higher wsp (25.31-37.94 µg/mm3) and wsl (0.08-8.27 µg/mm3), but also higher EIT (3.11-4.09 GPa) and FS (60.81-99.57N/mm2) values than the control groups. DEN and VPR showed high DC (89.36-93.53%), EIT (3.77-4.09 GPa) and FS (79.65-99.57N/mm2), while FOT showed low wsp (25.31-27.35 µg/mm3) and wsl (1.01-3.87 µg/mm3) values. In all materials, the examined parameters were affected by aging. SIGNIFICANCE: Although 3D-printed denture base resins showed promising results with regard to the observed DC and FS, only FOT and FRE surpassed the threshold values defined by the ISO norms.

Causes of death and determinants of outcome in critically ill patients.

INTRODUCTION: Whereas most studies focus on laboratory and clinical research, little is known about the causes of death and risk factors for death in critically ill patients. METHODS: Three thousand seven hundred patients admitted to an adult intensive care unit (ICU) were prospectively evaluated. Study endpoints were to evaluate causes of death and risk factors for death in the ICU, in the hospital after discharge from ICU, and within one year after ICU admission. Causes of death in the ICU were defined according to standard ICU practice, whereas deaths in the hospital and at one year were defined and grouped according to the ICD-10 (International Statistical Classification of Diseases and Related Health Problems) score. Stepwise logistic regression analyses were separately calculated to identify independent risk factors for death during the given time periods. RESULTS: Acute, refractory multiple organ dysfunction syndrome was the most frequent cause of death in the ICU (47%), and central nervous system failure (relative risk [RR] 16.07, 95% confidence interval [CI] 8.3 to 31.4, p < 0.001) and cardiovascular failure (RR 11.83, 95% CI 5.2 to 27.1, p < 0.001) were the two most important risk factors for death in the ICU. Malignant tumour disease and exacerbation of chronic cardiovascular disease were the most frequent causes of death in the hospital (31.3% and 19.4%, respectively) and at one year (33.2% and 16.1%, respectively). CONCLUSION: In this primarily surgical critically ill patient population, acute or chronic multiple organ dysfunction syndrome prevailed over single-organ failure or unexpected cardiac arrest as a cause of death in the ICU. Malignant tumour disease and chronic cardiovascular disease were the most important causes of death after ICU discharge.