scholarly journals Evaluation of the surface properties of modified Ni-Ti arch wires

2021 ◽  
Vol 11 (Suppl. 1) ◽  
pp. 167-175
Author(s):  
Hakkı Yılmaz ◽  
Fundagül Bilgiç Zortuk ◽  
Ali Tuncay Özyılmaz

Aim: Materials used in orthodontic treatment can cause corrosion and metal ion release to the mouth. This study was aimed to examine the changes in the friction coefficients and corrosion resistance of the modified Ni-Ti arch wires. Methodology: Our sample consisted of 16 Ni-Ti arch wires (0.016 × 0.022 inches). Coating bathes involving Ni-Ti, Ni-Ti-Mo, and Ni-Ti-Cr were prepared for arch wires coating. New surfaces were analyzed by SEM, and the crystallographic structure was determined by X-rays. The friction coefficient of the coated wires was determined by nanoindentation. Artificial saliva was prepared as a corrosive condition. Impedance measurements were performed with an electrochemical analyzer. The AC impedance spectroscopy measurements were performed after four hours, seven, 15, 30, 45, and 60 days. Results: All groups were more resistant than the control group (-447 mV) [group 1 (-388 mV), group 2 (-328 mV), group 3 (-327 mV), group 4 (-427 mV), group 5 (-395 mV), group 6 (-366 mV), and group 7 (-380 mV)]. Friction coefficients of group 5 (0.252) and group 6 (0.265) were observed to be lower than those of the control group (0.288). Conclusion: In the results of our study, it was shown that the surface properties of Ni-Ti wires could be electrochemically improved. The coated wires (group 5 and group 6) had a remarkable corrosion resistance and reduced friction. The protocols that we used should help provide better-quality surfaces.   How to cite this article: Özyılmaz AT, Bilgiç Zortuk F, Yılmaz H. Evaluation of the surface properties of modified ni-ti arch wires. Int Dent Res 2021;11(Suppl.1):167-176. https://doi.org/10.5577/intdentres.2021.vol11.suppl1.25   Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.  

2018 ◽  
Vol 2 ◽  
pp. 39
Author(s):  
Shahinur Nahar Moury ◽  
Md. Touhiduzzaman Sarker ◽  
Adhita Sri Prabakusuma ◽  
Md. Imrul Hasan Russel ◽  
Md. Shahidul Islam

The main purpose of this study was to explore the effects of Spirulina (Spirulina platensis) as a feed supplement by replacing Vitamin-Mineral Premix on the performance of broiler. The study explored that final body weight was 1039, 1070, 1044, 1065, 1117 and 893 g/bird in group 1, 2, 3, 4, 5 and 6 where significantly (p<0.5) higher weight observed in Spirulina group (5) but lower in negative control group (6). Feed intake observed more or less similar in all groups (1483±24g; p>0.5). Feed conversion ratio (kg FI/kg LWG) observed significantly different like 1.72, 1.65, 1.69, 1.62, 1.61 and 1.99 in group 1, 2, 3, 4, 5 and 6 respectively (p<0.5) where higher in negative group (6) and control group (1), but is lowest and similar in 75% Spirulina group (4) and highest (100%) Spirulina group (5). %Ash of different dietary groups were 46.35, 46.54, 48.93, 49.93, 55.07 and 46.92 of group 1, 2, 3, 4, 5 and 6 respectively. The %ash of bone was gradually increased among dietary groups and the best result was obtained in 100% Spirulina group 5 (55.07). It also revealed that diets containing no vitamin-mineral premix with 100% Spirulina improve the performance of broiler. The findings suggest that poultry farmer can use spirulina as a feed item for broiler for more yield.


Author(s):  
Auwal Balarabe Bello ◽  
Mudassir Lawal ◽  
A. Muhammad Hisbullahi

Aim: The aim of this study is to compare the protective effect of zinc nanoparticle and zinc supplement against carbamazepine induced reproductive changes in male Albino rats. Study Design: In this experiment, 60 Male albino rats were used which are divided into six groups of 10 rats each. The first group was used as the control for the experiment and they were given distilled water. The second Group, Group 2 were administered with 20 mg/kg body weight of carbamazepine, group 3 were administered with 20 mg/kg of carbamazepine plus 10 mg/kg of zinc nanoparticle and Group 4 were administered with 20 mg/kg of carbamazepine plus 10 mg/kg of zinc supplement while group 5 were administered with 10 mg/kg of zinc nanoparticle and also group 6 were administered with 10 mg/kg of zinc supplement only. Place and Duration of Study: Department of Biochemistry, Bells University of technology, Ota, Ogun State Nigeria, the research was carried out from February to June, 2018. Methodology: Zinc nanoparticle extraction was carried out to obtained Zinc nanoparticle. A 60 male albino rats with weight ranging from 140 g - 230 g were used. They were fed with normal rat chow and were allowed to acclimatize for a period of two weeks. They were then divided into six groups according to their body weight which contained the test groups and the control group. The rats were sacrificed after two weeks of test administration. They were allowed an overnight fast (24 hours). The cervical dislocation was done, and the blood was collected from the heart, in to a lithium heparinized bottle. The testes of the rats were also collected and stored in a sample bottle containing buffer and stored, the liver, kidney and the brain were collected too. The rats liver and testes were weight and macerated in 5 times the volume of the actual organ weight using homogenate buffer (phosphate buffer). The resulting homogenate was centrifuge at 10000 rmp speed for 15 mins then it was removed from the centrifuge and the supernatant was decanted and stored below 4°C. Result: The group administered with carbamazepine only show significant decreased in the level of follicle stimulating hormone, luteinizing hormone and testosterone when compared with control group, followed by the group administered with zinc nanoparticle only. However, group 6 and group 4 that were administered with zinc supplement and zinc supplement plus carbamazepine showed a significant increase in the level of these hormones when compared with control group, while group 6 which were administered with carbamazepine and zinc nanoparticle showed no significant different when compared with control group. In addition carbamazepine alone significantly increased the level of alanine transaminase (ALT) in the liver and also the group administered with zinc nanoparticle alone significantly increased the level of aspartate transaminase (AST) with decrease in the level of ALT. However, the groups administered with zinc supplement alone and in combination with carbamazepine reduced ALT and AST levels in the liver. Conclusion: Therefore, this study suggest that, carbamazepine induced toxicity by affecting the level of sex hormones and activities of the kidney in the male albino rats, and also zinc nanoparticle have more protective effect than zinc supplement against carbamazepine toxicity.


Author(s):  
Huseyin Gungor ◽  
Haki Kara

AbstractBackgroundThe aim of this study was to investigate the effects of selenium, zinc, insulin, and metallothionein on oxidative damage and metallothionein (MT) gene expression levels in streptozotocin (STZ)-induced type 1 diabetic rats exposed to Cd.MethodsRats were categorized under eight groups (control, STZ, Cd, STZ + Cd, Group 5, Group 6, Group 7, and STZ + Cd + MT [n:8/group]) were used. After diabetes was induced by STZ (55 mg/kg, i.p.), Cd was administered (1 mg/kg CdCl, orally) for 4 weeks. In cadmium-treated groups selenium (Na2SeO3 1.5 mg/kg, i.p.), zinc (ZnSO4 10 mg/kg via oral gavage), insulin (insulin glargine, 2U/day, s.c.), and MT (1mg/kg, every other 10 days, s.c.) were administered. MT gene expression levels, MDA levels, GPx, SOD, and CAT activity levels were determined in liver and kidney tissues.ResultsMT gene expression and MDA levels increased (p < 0.05) while GPx and SOD activity levels decreased (p < 0.05) in STZ, Cd, and STZ + Cd groups. In Group 5, Group 6, Group 7, and Group 8 groups MT gene expression and MDA levels were decreased while GPx and SOD activity levels were increased (p < 0.05). CAT activity significantly increased (p < 0.05) in STZ + Cd group while there were no significance in other groups (p > 0.05). Compared to the control, Group 5, Group 6, Group 7, and Group 8 groups provided no difference for alanine aminotransferase, aspartate aminotransferase, blood urea nitrogen and creatinine levels (p > 0.05).ConclusionsOur results suggest that Se, insulin, Zn and MT may have protective effects against hepatotoxicity and nephrotoxicity caused by Cd exposure in diabetic rats by reducing oxidative stress and MT gene expression levels.


2017 ◽  
Vol 20 (2) ◽  
pp. 67-72 ◽  
Author(s):  
Jennifer E Thomas ◽  
Cameon M Ohmes ◽  
Mark E Payton ◽  
Joseph A Hostetler ◽  
Mason V Reichard

Objectives The objectives of the present study were to determine the duration of infestation by Amblyomma americanum necessary for transmission of Cytauxzoon felis to domestic cats and to determine if ingestion of C felis-infected A americanum by cats is a route of transmission. Methods Forty-nine cats were assigned to one of seven groups, with seven cats per group. Cats were infested with A americanum adults, acquisition fed as nymphs on a cytauxzoonosis survivor cat, for 12 h (group 1), 18 h (group 2), 24 h (group 3), 36 h (group 4), 48 h (group 5) and to repletion (group 7; control). Cats in group 6 were fed C felis-infected ticks. Thumb counts were performed at the end of the duration of infestation for groups 1–5 and at 48 h for the control group. For group 6, 50 live C felis-infected adult A americanum were mixed with food and fed to each of the cats. Transmission of C felis was determined by examining blood of cats by DNA extraction followed by PCR. Results Of 50 ticks placed on each cat (groups 1–5 and 7), the arithmetic mean attachment ± SEM ranged from 46.9 ± 1.9 in group 3 to 49.3 ± 0.3 in group 1. In group 6, the average number ± SEM of ticks ingested was 46.5 ± 2.3. One cat in group 5 that had been infested for 48 h became infected with C felis. None of the cats in group 6 (ingestion) became infected with C felis. Six of 7 (85.7%) cats in group 7, the control group, became infected with C felis. Conclusions and relevance Our results indicate that transmission of C felis to domestic cats can happen as quickly as >36 h but ⩽48 h of exposure to A americanum infected with C felis and that ingestion of C felis-infected A americanum is not a likely route of transmission.


2020 ◽  
Vol 17 (36) ◽  
pp. 128-139
Author(s):  
Ekhlas A ALANI ◽  
Mustafa S ALMUSAWI ◽  
Amar H MAHDI

An interesting feature of ionizing radiation, especially Gamma and X-rays as a DNA damaging factor is the range of lesions it induces. γ-H2AX foci are documented to represent DNA double-strand breaks (DSBs) as a biomarker for radiation-induced damage. Study design 42 adult male mice Albino BALB/c, had been divided randomly into 6 groups of seven mice each. Group 1 received a standard saline solution untreated also, do not expose to radiation. Group 2 mice received vitamin C (VC) (200 mg/kg.day) intra-peritoneal (i.p.) injected for 8 days without radiation. Group 3 control was exposed to γ-radiation. Group 4 control was exposed to X-ray radiation. Group 5 mice had been administrated with vitamin C in the identical dose of group 2 for 8 days, then exposed to (4 Gy) of γ-ray. Group 6 was administrated with vitamin dose in the same above and the same period, then exposed to (4 Gy) of X-ray. All groups had been sacrificed by cervical dislocation at (1, 3, and 24 h). Post radiation testis mice tissues were collected. A significant difference (P 0.05) between the group of vitamin C and with a control group exposed to both (γ, X-rays) in foci forming, but there is no significant difference (P 0.05) between γ and X- rays for the control and vitamin C groups. The results demonstrate that vitamin C is a good radioprotective agent for testis mice tissues; the effect of (γ and X-rays) had almost the same results on the mice testicle tissues with the same dose.


2011 ◽  
Vol 36 (3) ◽  
pp. 318-325 ◽  
Author(s):  
M Özcan ◽  
C Koolman ◽  
A Aladag ◽  
M Dündar

SUMMARY Repairing amalgam restorations with composite resins using surface conditioning methods is a conservative treatment approach. This study investigated the effects of different conditioning methods that could be used for repair of amalgam fractures. Amalgam (N=96) was condensed into cavities within autopolymerizing polymethylmethacrylate (PMMA), and the exposed surface of each specimen (diameter, 6 mm; thickness, 2 mm) was ground finished. The specimens were randomly divided into nine experimental groups (n=12 per group), depending on the conditioning method used. The control group had natural central incisors with amalgam (n=12). The combination of the following conditioning methods was tested: silicacoating (Sc), sandblasting (Sb), metal primers, coupling agents, fiber (Fb) application, and opaquers (O). Five types of silanes, metal primers, or adhesives (Visiobond [V], Porcelain Photobond [PP], Alloy Primer [AP], Unibond sealer [Us], ESPE-Sil [ES]), and four opaquers, namely, Clearfil St Opaquer (CstO), Sinfony (S), Miris (M), and an experimental Opaquer (EO-Cavex), were used. The groups were as follows: group 1, Sc+ES+S+V; group 2, Sc+ES+CstO+V; group 3, Sc+ES+M+V; group 4, Sc+ES+EO+V; group 5, Sb+AP+S; group 6, Sb+AP+PP+CstO; group 7, Sc+ES+S+Fb+V+Fb; group 8-control, SC+ES+V; and group 9, Etch+Sc+ES+S+Us. One repair composite was used for all groups (Clearfil Photo Bond Posterior, Kuraray, Tokyo, Japan). Shear bond strengths (SBSs) (MPa ± SD) were evaluated after 5 weeks of water storage (analysis of variance [ANOVA], Tukey honestly significant differences [HSD], α=0.05). Group 1 exhibited significantly higher values (35.5 ± 4.1) than were seen in group 4 (19.4 ± 8.9), group 6 (19.1 ± 7.8), and group 8 (20.1 ± 4.1) (p&lt;0.05). Group 9 exhibited significantly lower values (8.3 ± 3.4) than were noted in groups 1 to 3 (35.5 ± 4.1; 27 ± 12.5; 24.4 ± 5.1, respectively) (p&lt;0.05). Group 7 (16.4 ± 5.9) showed significantly lower values than were observed in group 1 (35.5 ± 4.1) (p&lt;0.05). Surface conditioning techniques affected the bond strengths of composite adhesion to amalgam. Experimental opaquer exhibited lower values. Leaving a small border of enamel around the restoration decreased the bond strength.


2017 ◽  
Vol 87 (3-4) ◽  
pp. 179-190
Author(s):  
Amel Kanane ◽  
Fayrouz Rouaki ◽  
Mohamed Brahim Errahmani ◽  
Abdenour Laraba ◽  
Hayet Mesbah ◽  
...  

Abstract. The aim of this study is to evaluate the effect of α-tocopherol supplementation at two doses (600 and 1200 mg × kg–1) on kidney antioxidant status and the histopathological changes in Wistar rats after 12 weeks of exposure at different diets. Forty rats has been divided into 4 groups of 10 rats each, the control group received basal diet with 5 % fresh sunflower oil (FSO), the second group: 5 % oxidized sunflower oil (OSO), the third group: 5 % OSO supplemented with 600 mg × kg–1 α-tocopherol and the fourth group: 5 % OSO supplemented with 1200 mg × kg–1 α-tocopherol. In OSO groups, the results showed highly significant increases of LPO (from 31.3 ± 0.9 to 53.8 ± 1.2 nmol of MDA formed/min/mg protein, p < 0.0001) with a significant decrease (p < = 0.001) of the antioxidant enzymatic activities (CAT, SOD, GPX, GR and G6PDH), body weight (339 ± 9 to 290 ± 3 g) and α-tocopherol levels (13.6 ± 0.6 to 6.5 ± 0.4 μg/mg protein). In OSO groups with 600 mg × kg–1 α-tocopherol, an antioxidant effect was found, reflected by a return of the parameters to values similar to those of the control group. However, higher doses of α-tocopherol (1200 mg × kg–1) induced a depletion of antioxidant status, α-tocopherol levels (6.0 ± 0.3 μg/mg protein, p < 0.001) and a very highly significant rise (p < 0.0001) of LPO content (54.86 ± 0.01 nmol of MDA formed/min/mg protein). The kidney tissues also showed changes in glomerular, severe inflammatory cells infiltration, and formation of novel vessels. So, we can conclude that the oxidative stress is attenuated by a moderate administration of 600 mg × kg–1 α-tocopherol, while a pro-oxidant effect occurs at 1200 mg × kg–1 α-tocopherol.


Author(s):  
Vicente Jesús León-Muñoz ◽  
Mirian López-López ◽  
Alonso José Lisón-Almagro ◽  
Francisco Martínez-Martínez ◽  
Fernando Santonja-Medina

AbstractPatient-specific instrumentation (PSI) has been introduced to simplify and make total knee arthroplasty (TKA) surgery more precise, effective, and efficient. We performed this study to determine whether the postoperative coronal alignment is related to preoperative deformity when computed tomography (CT)-based PSI is used for TKA surgery, and how the PSI approach compares with deformity correction obtained with conventional instrumentation. We analyzed pre-and post-operative full length standing hip-knee-ankle (HKA) X-rays of the lower limb in both groups using a convention > 180 degrees for valgus alignment and < 180 degrees for varus alignment. For the PSI group, the mean (± SD) pre-operative HKA angle was 172.09 degrees varus (± 6.69 degrees) with a maximum varus alignment of 21.5 degrees (HKA 158.5) and a maximum valgus alignment of 14.0 degrees. The mean post-operative HKA was 179.43 degrees varus (± 2.32 degrees) with a maximum varus alignment of seven degrees and a maximum valgus alignment of six degrees. There has been a weak correlation among the values of the pre- and postoperative HKA angle. The adjusted odds ratio (aOR) of postoperative alignment outside the range of 180 ± 3 degrees was significantly higher with a preoperative varus misalignment of 15 degrees or more (aOR: 4.18; 95% confidence interval: 1.35–12.96; p = 0.013). In the control group (conventional instrumentation), this loss of accuracy occurs with preoperative misalignment of 10 degrees. Preoperative misalignment below 15 degrees appears to present minimal influence on postoperative alignment when a CT-based PSI system is used. The CT-based PSI tends to lose accuracy with preoperative varus misalignment over 15 degrees.


Author(s):  
Mustafa Salah Hasan ◽  
Ayman Barzan Abdulgafor ◽  
Maher Saber Owain ◽  
Mohammed Ali Hussein ◽  
Qusay Mohammed Aboud ◽  
...  

This study aimed to evaluate the liver, kidney damage caused by S. typhimurium and to estimate the oxidative damage in association with this bacteria. A highly virulent isolates of S. typhimurium were obtained from the department of internal and preventive medicine/ College of Veterinary Medicine/ University of Baghdad. A twenty five local rabbits of both genders with age range (2-4 months) weeks old were used for this study, the rabbits were divided randomly into five groups each group contains 5 rabbits :- group 1: drenched orally with 5 ml of normal saline and consider as control group, group 2: were drenched orally with (5 ml) suspension which contain (5��109 CFU) of Salmonella typhimurium and regarded as infected group, group 3 were drenched orally with (5 ml) suspension which have (5��109 CFU) of Salmonella typhimurium then treated with a single dose of gentamicin alone at 0.05ml/kg (5mg/ml) orally after presence of signs (after 24hrs. post inoculation), group 4 were drenched (5 ml) suspension having (5��109 CFU) of Salmonella typhimurium then treated with a single dose of Ca-EDTA alone at 40mg/kg orally after presence of signs (after 24hrs. post inoculation) and group 5 were drenched (5 ml) suspension that contain (5��109 CFU) of Salmonella typhimurium then treated with a single dose of combined gentamicin at 0.05ml/kg (5mg/ml) orally after presence of signs (after 24hrs. post inoculation) and Ca-EDTA 40mg/kg after presence of signs (after 24hrs. post inoculation).The results of biochemical profile showed a significant increase (p less than 0.05) in ALT, creatinine and urea levels in infected group as compared with control group, while, the treated groups especially group 5 showed a significant improvement in ALT, Urea and creatinine levels which returned to relative normal levels as compared with infected group after 96hrs. post treatment. Also, the results of oxidative stress showed a significant increase in the levels of MDA in G2, G3, G4 and G5 after 48 hrs. post treatment, while the level of GSH showed a significant decrease in the level at 48hrs., both were returned to relative normal levels after 96hrs.post treatment especially in group 5.In conclusion, S. typhimurium can causing liver and kidney damage which is manifested by increase ALT, Urea and Creatinine. Also, MDA and GSH is increased due to salmonellosis.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yu Liu ◽  
Jing Li ◽  
Wanyu Zhang ◽  
Yihong Guo

AbstractOestradiol, an important hormone in follicular development and endometrial receptivity, is closely related to clinical outcomes of fresh in vitro fertilization-embryo transfer (IVF-ET) cycles. A supraphysiologic E2 level is inevitable during controlled ovarian hyper-stimulation (COH), and its effect on the outcome of IVF-ET is controversial. The aim of this retrospective study is to evaluate the association between elevated serum oestradiol (E2) levels on the day of human chorionic gonadotrophin (hCG) administration and neonatal birthweight after IVF-ET cycles. The data of 3659 infertile patients with fresh IVF-ET cycles were analysed retrospectively between August 2009 and February 2017 in First Hospital of Zhengzhou University. Patients were categorized by serum E2 levels on the day of hCG administration into six groups: group 1 (serum E2 levels ≤ 1000 pg/mL, n = 230), group 2 (serum E2 levels between 1001 and 2000 pg/mL, n = 524), group 3 (serum E2 levels between 2001 and 3000 pg/mL, n = 783), group 4 (serum E2 levels between 3001 and 4000 pg/mL, n = 721), group 5 (serum E2 levels between 4001 and 5000 pg/mL, n = 548 ), and group 6 (serum E2 levels > 5000 pg/mL, n = 852). Univariate linear regression was used to evaluate the independent correlation between each factor and outcome index. Multiple logistic regression was used to adjust for confounding factors. The LBW rates were as follows: 3.0% (group 1), 2.9% (group 2), 1.9% (group 3), 2.9% (group 4), 2.9% (group 5), and 2.0% (group 6) (P = 0.629), respectively. There were no statistically significant differences in the incidences of neonatal LBW among the six groups. We did not detect an association between peak serum E2 level during ovarian stimulation and neonatal birthweight after IVF-ET. The results of this retrospective cohort study showed that serum E2 peak levels during ovarian stimulation were not associated with birth weight during IVF cycles. In addition, no association was found between higher E2 levels and increased LBW risk. Our observations suggest that the hyper-oestrogenic milieu during COS does not seem to have adverse effects on the birthweight of offspring after IVF. Although this study provides some reference, the obstetric-related factors were not included due to historical reasons. The impact of the high estrogen environment during COS on the birth weight of IVF offspring still needs future research.


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