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Background: Increased time from symptom onset to puncture (TSOP) and time from puncture to reperfusion (TPTR) are associated with worse outcome in ischemic stroke patients treated with endovascular therapy (EVT) in the early time window (<6 h). However, these associations are less described in the late window (>6 h), where patients may benefit from EVT because of a more favorable imaging profile (late window paradox). We sought to compare the effect of these timeframes between these two periods on efficacy and safety outcomes., Methods: The ETIS (Endovascular Treatment in Ischemic Stroke) registry is an ongoing, prospective, observational study in 21 centers that perform EVT in France. We included adult patients with an anterior occlusion, successfully treated by EVT (modified treatment in cerebral ischemia (mTICI) 2b-3) between January 2015 and June 2023, with a known time of stroke onset. The cohort was divided into two groups according to the TSOP (⩽6 h vs >6 h). Primary outcome was favorable outcome (modified Rankin Scale 0-2 at 90 days)., Results: In total, 7516 patients were included, with 5936 patients being treated ⩽6 h and 1580 >6 h. In the early window, TSOP and TPTR were associated with worse outcomes at 90 days (adjusted odds ratio (aOR) = 0.68 per hour; 95% confidence interval (CI) = 0.64-0.73; p  < 0.001 and aOR = 0.92 per 10-min increment; 95% CI = 0.90-0.94, p  < 0.001, respectively). TSOP was not associated with worse outcomes at 90 days in the late window ( p  = 0.955), but TPTR was associated with worse outcomes (aOR = 0.91 per 10-min increment; 95% CI = 0.86-0.96, p  = 0.001), every 10 additional minutes in TPTR being associated with a 1.7% (95% CI = 0.6-2.7) decreased probability of favorable outcome., Conclusion: Only EVT procedural time is associated with unfavorable outcomes at 90 days in late window patients. These results highlight how the late window paradox may end at the start of EVT and underscore the need for timely management, particularly for the EVT, even for late window patients with a presumed more favorable imaging profile., Competing Interests: Declaration of conflicting interestThe author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: J.-M.O. declares consulting activities with Abbvie, Acticor, and Bioxodes; speaking fees from BMS, Boerhinger Ingelheim; S.F. is the author of a patent (US20200085454A1). B.G. has received grants from the French Ministry of Health and is the primary investigator of the TITAN, DIRECT ANGIO, and IA-RESCUE trial, and consulting fees from Air Liquide, MIVI, Medtronic, Microvention, and Penumbra. M.M. declares consulting fees from Boerhinger Ingelheim, Air Liquide, Acticor Biotech, and Amgen. S.R. declares contracts from Boerhinger Ingelheim France, Bristol-Myers Squibb, and Pfizer SAS.

Background: The purpose of this work is to evaluation of contact-wear behavior of lithium disilicate glass ceramic materials under in vitro chewing tests. Methods: Eight specimens of each ceramic materials were exposed contact-wear tests using a computer-controlled chewing simulator (1.2 Hz 50 N bite force loads, 120.000 mechanical cycles, constantly 37 °C temperature immersed in distill water. Al2O3 balls of 6 mm in diameter were used for each chewing test. The mean volume loss of all ceramic specimens after the contact-wear tests was determined with use 3D profilometer. In addition to a random specimen was selected from each test group and scanning electron microscopy (SEM) images were taken for analysis of wear tracks. Results: As a result, the ceramic materials tested in this study showed similar wear behaviors after 120.000 chewing tests. Conclusions: However, it was observed that more particles were carried on the wear surface and occurred micro cracks of the IPS e.max ceramic material. These micro cracks can be the continuation of cracks that occur subsurface of ceramic material.

Background: The thermal changes in environments that composite materials are exposed to has a great effect on fatigue and wear behavior. Aim: Micro-cracks and interfacial deformations occur in the composite material structure because of heating and cooling environments occurring on material surfaces. Considering the environment to which bio-composite materials used in the human body are exposed, it is inevitable that they are exposed to a thermal change cycle environment. Material and Method: In this study, the mechanical behaviors of Silorane, X-Trafil and Valux-Plus bio-composite materials were examined after being exposed to thermal cycles in an artificial mouth environment in the temperature range of minimum 5 °C and maximum 65 °C. Micro-tensile strengths of bio-composite materials after thermal cycle test procedures were determined using a universal micro tensile tester device. In addition, microstructural analyzes of bio-composite materials were evaluated using scanning electron microscopy (SEM). Results: Within the scope of the data obtained as a result of this study, it was concluded that the thermal changes in environments significantly affects the micro-shrinkage behavior of bio-composite materials. Conclusion: The behavior of the matrix structure of the composite material significantly affected the formation of micro cracks.

Background: The purpose of the present study was to investigate effects of contact-stress on direct-contact wear behavior of zirconia reinforced lithium silicate glass-ceramic; in vitro off-axis sliding contact chewing simulation. Methods: In this study, 12 mm diameter X 2 mm thickness in size of lithium disilicate, Vita Suprinity; zirconia-reinforced lithium silicate was used. The test specimens were subjected to 100.000 mechanical loading, 3000 thermal cycles, 1.2 Hz wear frequency, 30° angle 0.7 mm lower jaw movement and different size Al2O3 antagonist material in artificial saliva. The average wear volume loss of the test specimens was obtained after wear test procedure using non-contact 3D profilometer. Furthermore, micro-structure analyzes of the wear surfaces of the test specimens were performed using scanning electron microscopy (SEM) and atomic force microscopy (AFM). Results: As a result of this study, ceramic material showed better abrasion resistance with increasing contact surface of abrasive material. Conclusion: However, microstructure analysis has shown that micro cracks occur on the wear surfaces both wear test procedures. These micro cracks may have occurred under the wear surface of the ceramic material.

In this study, the impact wear behaviour of Al-5Mg, used as a corrosion protective coating was investigated in seawater and air environments. Tests were conducted for up to 105 cycles on the plane surface of Al-5Mg coated AISI 316L samples. Wear at the frequency of 2.5 Hz kept the coating thickness at a reliable level. However, the wear that occurred under the frequency of 5Hz reached the substrate surface. In the experiments conducted in seawater, smoother wear scars were formed compared to those in the air environment tests. The coating particles separated by the wear effect were compressed by the impactor on the wear surface with repetitive impacts, causing delamination. Friction oxidation was formed on wear scars. The hydrodynamic effect of seawater reduced the delamination by removing the separated coating particles from the surface. Thus, in seawater, 70% more wear occurred compared to in the air environment. [ABSTRACT FROM AUTHOR]