Comparative cone-beam computed tomography evaluation of the osseous morphology of the temporomandibular joint in temporomandibular dysfunction patients and asymptomatic individuals

We examined the bone components of the temporomandibular joint (TMJ) in asymptomatic individuals and patients with temporomandibular dysfunction (TMD) using cone-beam computed tomography (CBCT). Two hundred asymptomatic individuals and 200 patients with TMD were included in this study. Condyle position, eminence height, eminence inclination, condyle shape, and fossa shape were assessed on CBCT images of the 800 temporomandibular joints. The eminence inclination (P < 0.05), eminence height (P < 0.0001), mediolateral width of condyle (P < 0.0001), and anterior joint space (P < 0.0001) were significantly greater in male subjects compared with female subjects in both the asymptomatic group and TMD group. Comparisons of the asymptomatic group and TMD group revealed significant differences in the anterior joint space (P < 0.0001), ratio of anterior joint space to posterior joint space (P < 0.001), posterior joint space (P < 0.05), eminence inclination (P < 0.05), eminence height (P < 0.05), condyle shape (P < 0.0001), and fossa shape (P < 0.05). The present analyses suggest that a steeper articular eminence inclination may be risk factor for TMD. The presence of TMD was associated with the condyle position in the TMJ

Effects of flash annealing and external magnetic field on magnetic properties of relatively high Nd content (37% by weight) NdFeB alloy

Post modifications such as alloying element addition and/or heat treatment are applied to improve the magnetic properties of NdFeB permanent magnets. In this study, effects of external magnetic field and flash annealing at different temperatures (680 degrees C and 710 degrees C) and durations of 5 and 10 min on the magnetic properties of relatively high Nd content (37 wt.%) NdFeB magnet alloys were investigated. Melt spinning method was used in production of the NdFeB magnet alloys. Heat treatment was applied to various NdFeB magnet ribbons at 680 degrees C and 710 degrees C temperatures for 5 and 10 min by the flash annealing at heating and cooling rates of 300 K/s. In addition, before vibrating sample magnetometer tests, various samples were magnetized under an external magnetic field of 5 Tesla. After melt spinning, semi-amorphous structure was obtained and Nd2Fe14B hard and alpha-Fe soft magnetic phases were crystallized at nanoscale by flash annealing. These crystallizations formed between approximately 350 degrees C and 430 degrees C. After the flash annealing, residual amorphous structures were observed without complete crystallization. The highest remanence and coercivity were obtained in the sample flash annealed for 10 min at 710 degrees C, 57.64 emu/g and 10,419.07 Oe, respectively. The maximum energy product improved thanks to the high remanence and coercivity, important for the NdFeB magnets resulted in a high value of 87.79 kJ/m(3) in the same sample. This flash annealing procedure provides a cost-effective and simple platform to improve the magnetic features of NdFeB magnets

Centrifugally spun silica (SiO2) nanofibers for high-temperature air filtration

Polat, Yusuf/0000-0002-4807-7002; KILIC, ALI/0000-0001-5915-8732; Calisir, Mehmet Durmus/0000-0002-5916-9666; Akgul, Yasin/0000-0001-5643-5968WOS: 000469605000001In this study, silica-based nanofibers were produced via centrifugal spinning (C-spin) and subsequent calcination. the produced heat resistant media was challenged with NaCl nanoparticles to investigate their filtration performance. To obtain inorganic SiO2 nanofibers, C-spun organic PVP-TEOS nanofibers were calcinated at 300-600 degrees C. Effects of solution concentration and calcination temperature on crystallinity, morphology and air filtration performance of nanofibers were investigated. Scanning electron microscopy (SEM) analysis was performed to analyze fiber diameter and morphology of nanofibrous webs. Differential thermal analysis (DTA) was realized for the thermal behavior of samples. Moreover, X-ray diffraction (XRD) and Fourier transform infrared spectra (FTIR) analysis were realized for further characterization. in addition to the chemical and morphological analysis, the ductility of the samples was investigated via tensile tests. Finally, calcinated webs were challenged with 0.4 mu m salt particles to analyze their filtration performance. the calcinated 5 wt% TEOS/PVP silica nanofiber webs were more brittle due to three times lower precursor content. Therefore, flexibility (percent elongation) of 15 wt%TEOS/PVP sample was nearly five times higher than 5 wt%TEOS/PVP sample. the calcinated 15 wt%TEOS/PVP sample showed the highest filtration performance among all the silica nanofibers. the average fiber diameter of the optimized web was found to be the lowest, which is around 521 +/- 308 nm, which resulted in enhanced filtration efficiency around 75.89%. Copyright (c) 2019 American Association for Aerosol ResearchScientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [214M371]; ITU Scientific Research Fund (ITU-BAP)Istanbul Technical University [39.606, 39.128]This work was supported by the Scientific and Technological Research Council of Turkey (TUBITAK) [grant number 214M371] and the ITU Scientific Research Fund (ITU-BAP) [grant number 39.606], [grant number 39.128]

The Survival of Well-Fixed Cementless Femoral Component After Isolated Acetabular Component Revision

Background It remains controversial whether isolated acetabular component revision or both component revision surgeries should be performed in patients with stable femoral component. The present study aimed to evaluate the survival of patients with unrevised stable uncemented femoral stem who underwent isolated acetabular component revision. Material and Methods A retrospective analysis was conducted in patients who underwent isolated acetabular component revision and had stable uncemented femoral component during revision hip arthroplasty between February 1998 and December 2009. Demographic data of the patients included age, previous surgery, complications, duration between primary and revision surgery, and duration between revision and latest follow-up. Functional results were analyzed using Harris Hip Score (HHS). Results Fifteen hips of thirteen patients were included in the study with a mean age of 62.08 +/- 12.9 years. Average time from THA to the isolated acetabular revision was 9.2 +/- 3.48 years. Average follow-up time from revision to the latest follow-up was 12.39 +/- 2.68 years, and femoral components had been followed for an average of 21.6 +/- 4.06 years since the time of implantation. Average HHS of the patients were 53 before revision surgery and 81.9 at the last follow-up (p < 0.001). The 10-year survival rate of patients who underwent revision in the femoral component was 100%, whereas their 15-year survival rate was 93.3%. None of the acetabular components required revision. Conclusion Isolated revision of acetabular component may be considered if there is stable uncemented femoral component in revision THA. Acetabular reconstruction quality, acetabular and unrevised femoral component survival are not affected by retaining well-fixed femoral component