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Variations in surface roughness of seven orthodontic archwires: an SEM-profilometry study
Amini, Fariborz,Rakhshan, Vahid,Pousti, Maryam,Rahimi, Hajir,Shariati, Mahsa,Aghamohamadi, Bahareh The Korean Association Of Orthodontists 2012 대한치과교정학회지 Vol.42 No.3
Objective: The purpose of this study was to evaluate the surface roughness (SR) of 2 types of orthodontic archwires made by 4 different manufacturers. Methods: This in vitro experimental study was conducted on 35 specimens of 7 different orthodontic archwires, namely, 1 nickel-titanium (NiTi) archwire each from the manufacturers American Orthodontics, OrthoTechnology, All-Star Orthodontics, and Smart Technology, and 1 stainless steel (SS) archwire each from the manufacturers American Orthodontics, OrthoTechnology, and All-Star Orthodontics. Aft er analyzing the composition of each wire by energy-dispersive X-ray analysis, the SR of each wire was determined by scanning electron microscopy (SEM) and surface profilometry. Data were analyzed using the Kruskal-Wallis and Mann-Whitney U tests (${\alpha}$ < 0.05). Results: The average SR of NiTi wires manufactured by Smart Technology, American Orthodontics, OrthoTechnology, and All-Star Orthodontics were $1,289{\pm}915A^{\circ}$, $1,378{\pm}372A^{\circ}$, $2,444{\pm}369A^{\circ}$, and $5,242{\pm}2,832A^{\circ}$, respectively. The average SR of SS wires manufactured by All-Star Orthodontics, OrthoTechnology, and American Orthodontics were $710{\pm}210A^{\circ}$, $1,831{\pm}1,156A^{\circ}$, and $4,018{\pm}2,214A^{\circ}$, respectively. Similar to the results of profilometry, the SEM images showed more defects and cracks on the SS wire made by American Orthodontics and the NiTi wire made by All-Star Orthodontics than others. Conclusions: The NiTi wire manufactured by All-Star Orthodontics and the SS wire made by American Orthodontics were the roughest wires.
Mazeyar Parvinzadeh Gashti,Izadyar Ebrahimi,Mohammad Pousti 한국물리학회 2015 Current Applied Physics Vol.15 No.9
The aim of the present work is to demonstrate the influence of corona discharge ionization on chemical and physical properties of polyethylene terephthalate (PET) fibers using computational and experimental studies. In the computational section, the vibrational frequencies of proposed models for PET before and after corona discharge treatment were predicted in the liquid phase at both the B3LYP/6-31G/COSMO and B3PW91/6-31G/COSMO level of theories using the harmonic approximation. When compared to B3LYP, the frequencies obtained for the B3PW91 show a better linear correlation with the experimental data. Furthermore, experimental studies were carried out by the use of Fourier transform infrared spectroscopy (FTIR), X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), and reflectance spectroscopy (RS). Experimental evidence indicated that the corona discharge modifies the surface of fibers and also increases the reactivity of PET toward cationic dyes. Our combined computational and experimental parametric study clearly confirms that the changes occurred on the PET surface due to corona discharge ionization.
Variations in surface roughness of seven orthodontic archwires
Fariborz Amini,Vahid Rakhshan,Maryam Pousti,Hajir Rahimi,Mahsa Shariati,Bahareh Aghamohamadi 대한치과교정학회 2012 대한치과교정학회지 Vol.42 No.3
Objective: The purpose of this study was to evaluate the surface roughness (SR) of 2 types of orthodontic archwires made by 4 different manufacturers. Methods: This in vitro experimental study was conducted on 35 specimens of 7 different orthodontic archwires, namely, 1 nickel-titanium (NiTi) archwire each from the manufacturers American Orthodontics, OrthoTechnology, All-Star Orthodontics, and Smart Technology, and 1 stainless steel (SS) archwire each from the manufacturers American Orthodontics, OrthoTechnology, and All-Star Orthodontics. After analyzing the composition of each wire by energydispersive X-ray analysis, the SR of each wire was determined by scanning electron microscopy (SEM) and surface profilometry. Data were analyzed using the Kruskal-Wallis and Mann-Whitney U tests (α < 0.05). Results: The average SR of NiTi wires manufactured by Smart Technology, American Orthodontics, OrthoTechnology, and All-Star Orthodontics were 1,289 ± 915 A˚, 1,378 ± 372 A˚, 2,444 ± 369 A˚, and 5,242 ± 2,832 A˚, respectively. The average SR of SS wires manufactured by All-Star Orthodontics, OrthoTechnology, and American Orthodontics were 710 ± 210 A˚, 1,831 ± 1,156 A˚, and 4,018 ± 2,214 A˚, respectively. Similar to the results of profilometry, the SEM images showed more defects and cracks on the SS wire made by American Orthodontics and the NiTi wire made by All-Star Orthodontics than others. Conclusions: The NiTi wire manufactured by All-Star Orthodontics and the SS wire made by American Orthodontics were the roughest wires.