PLAYERS The first magazine dedicated to young female athletes and women’s college sports fans.

The involvement of women in athletics has exploded over the last 10 years. This project capitalizes on this changing dynamic by creating a prototype of a women’s college sports magazine called Players. No such magazine currently exists in the United States, but I believe there is a market for it among teenage female athletes who are interested in women’s college sports. Without Players, females have only male-dominated publications like Sports Illustrated or ESPN for general sports coverage, or they can read more female-friendly publications such as Shape and Fitness, which cater to an active lifestyle but do not cover sports. Women’s basketball fans can read Women’s Basketball, but it is a fairly obscure magazine that is hard to find, and it does only a mediocre job of covering women’s basketball and nothing more. Players, however, gives young female athletes and sports fans exactly what they are looking for in a magazine: NCAA news, player profiles, workout tips, fashion advice and entertainment. Going into this project, it was called to my attention that this generation seeks its news in short and simple messages. With that in mind, I kept the articles relatively brief and used many graphic elements and bold colors to keep my readers visually interested. I also focused--within the five broad categories mentioned previously--on topics that would grab readers’ attentions and hold them there, such as sports-themed films and issues of sexuality, for example. The goal of this magazine is to level the playing field between men’s and women’s sports coverage. Fans of men’s sports have a seemingly endless supply of magazines to reference, while women’s sports fans have only one. And no magazine provides a steady, in-depth view of women’s NCAA sports. I believe, however, the time has come for fans of women’s sports to have an equal opportunity to read and learn about their favorite teams and athletes, hence the creation of Player

Rotary fatigue testing to determine the fatigue life of NiTi alloy wires: an experimental and numerical analysis

Endodontic rotary file instruments used to treat root canals in dentistry suffered breakthrough transformations in recent years when stainless steel was replaced by Nickel-Titanium (NiTi). NiTi alloys used in Endodontics possess superelastic properties at body temperature (37C) that bring many advantages on the overall performance of the root-canal treatment. They can follow curved root canals more easily than stainless steel instruments and have been reported to be more effective in the removal of the inflamed pulp tissue and protection of the tooth structure. However, these instruments eventually fracture under cyclic bending loading due to fatigue, without any visible signals of degradation to the practitioner. This problem brought new challenges on how new Instruments should be tested, as NiTi alloys are highly non-linear and present a large hysteresis cycle in the Elastic domain. Current existing standards are only available for Stainless Steel testing. Thus, many authors have attempted to design systems that can test NiTi endodontic files under fatigue loads. However, no approach has been universally adopted by the community yet, as in most cases they are based on empirical set ups. Following a more systematic approach, this work presents the results of rotary fatigue tests for several NiTi wires from different manufacturers (Memry™ and Euroflex™ ).The formulation is presented, where the material strength reduction can be quantified from the determination of the strain and the number of cycles until failure, as well numerical FEM simulation to verify the analytical model predictions

New technologies to improve root canal disinfection

Effective irrigant delivery and agitation are prerequisites to promote root canal disinfection and debris removal and improve successful endodontic treatment. This paper presents an overview of the currently available technologies to improve the cleaning of the endodontic space and their debridement efficacy. A PubMed electronic search was conducted with appropriate key words to identify the relevant literature on this topic. After retrieving the full-text articles, all the articles were reviewed and the most appropriate were included in this review. Several different systems of mechanical activation of irrigants to improve endodontic disinfection were analysed: manual agitation with gutta-percha cones, endodontic instruments or special brushes, vibrating systems activated by low-speed hand-pieces or by sonic or subsonic energy, use of ultrasonic or laser energy to mechanically activate the irrigants and apical negative pressure irrigation systems. Furthermore, this review aims to describe systems designed to improve the intracanal bacterial decontamination by a specific chemical action, such as ozone, direct laser action or light-activated disinfection. The ultrasonic activation of root canal irrigants and of sodium hypochlorite in particular still remains the gold standard to which all other systems of mechanical agitation analyzed in this article were compared. From this overview, it is evident that the use of different irrigation systems can provide several advantages in the clinical endodontic outcome and that integration of new technologies, coupled with enhanced techniques and materials, may help everyday clinical practice

Rotary Fatigue Testing Machine to Determine the Fatigue Life of NiTi alloy Wires and Endondontic Files

Endodontic rotary file instruments used to treat root canals in dentistry suffered breakthrough transformations in recent years when stainless steel was replaced by Nickel-Titanium (NiTi). NiTi alloys used in Endodontics possess superelastic properties at body temperature (37C) that bring many advantages on the overall performance of the root-canal treatment. They can follow curved root canals more easily than stainless steel instruments and have been reported to be more effective in the removal of the inflamed pulp tissue and protection of the tooth structure. However, these instruments eventually fracture under cyclic bending loading due to fatigue, without any visible signals of degradation to the practitioner. This problem brought new challenges on how new instruments should be tested, as NiTi alloys are highly non-linear and present a large hysteresis cycle in the Elastic domain. Current existing standards are only available for Stainless Steel testing. Thus, many authors have attempted to design systems that can test NiTi endodontic files under fatigue loads. However, no approach has been universally adopted by the community yet, as in most cases they are based on empirical set ups. Following a more systematic approach, this work presents the results of rotary fatigue tests for several NiTi wires from different manufacturers (MemryTM and EuroflexTM). The tests were done on a versatile fully automatic rotary bending testing machine. The formulation is also presented, where the material strength reduction can be quantified from the determination of the strain and the number of cycles until failure

Título: Vida de Plotino

Contiene: T. I. 1.ª y 2.ª ennéadas. -- T. II. 3.ª y 4.ª ennéadas. -- T.III. 5ª y 6ª ennéadas. -- T. IV. Sexta enneada, conclusió

Determination of the rotary fatigue life of NiTi alloy wires

Nickel-Titanium (NiTi) alloys with superelastic properties have been increasingly introduced as a substitute to more conventional alloys, such as stainless steel, in a variety of applications. In Dentistry, NiTi alloys are used in tools such as Endodontic rotary files, allowing the file to follow teeth root canals more easily than their stainless steel counterparts. Nevertheless, during surgery, the file is subjected to cyclic bending loading, since it is rotating while being deformed inside the curved canals and is prone to fracture due to fatigue, without showing any visible signals of degradation. Following a systematic approach, this work presents the results of rotary fatigue tests for several NiTi wires from different manufacturers (Memry and Euroflex). The formulation is presented, where the material strength reduction can be quantified from the determination of the strain and the number of cycles until failure. Experimental tests as well as numerical Finite Element Analysis (FEA) simulations are presented to better understand the fatigue fracture mechanisms present in NiTi alloys, showing that there is good agreement between the predicted strains (difficult to measure in such small wires) and the cycles to failure

Influence of the shape of artificial canals on the fatigue resistance of NiTi rotary instruments

To investigate the influence of the trajectory of NiTi rotary instruments on the outcome of cyclic fatigue tests. Ten ProFile and Mtwo instruments tip size 20, taper 0.06 and tip size 25, taper 0.06 were tested in two simulated root canals with an angle of curvature of 60 degrees and radius of curvature of 5 mm but with different shape. Geometrical analysis of the angle and radius of the curvature that each instrument followed inside the two different artificial canals was performed on digital images. The instruments were then rotated until fracture at a constant speed of 300 rpm to calculate the number of cycles to failure (NCF) and the length of the fractured fragment. Mean values were calculated and analysed using two different multivariate linear regression models and an independent sample t-test. The shape of the artificial root canal used in cyclic fatigue studies influenced the trajectory of the instrument. This difference is reflected by the NCF measured for the same instrument in the different artificial root canals and by the impact of the type of canal on both the NCF (St.beta = 0.514) and fragment length (St.beta = -0.920). Small variations in the geometrical parameters of the curvature of an instrument subjected to flexural fatigue could have a significant influence on the results of fatigue tests

The impact of endodontic anatomy on clinical practice: a micro-CT study and tribute to Prof. Francesco Riitano

Aim: To evaluate the quality of root canal preparation using two different mechanical NiTi systems. Methodology: 40 maxillary and mandibular molars were selected. Specimens were randomly assigned to two groups and were scanned using a micro-computed tomography scanner before and after root canal preparation that was performed using ProFile instrument sequence and Reciproc single file technique. Each system was used to obtain an optimal apical size for each specimen, following common clinical guidelines. 3D models were reconstructed and evaluated for volume, areas and root canal axis. The total volume of dentine removed and the volume of the coronal, middle and apical thirds of each root canal were calculated, as well as the average deviation of the root canal axis at different levels and the values compared. Student t-test was used to determine the difference between the two experimental groups (P < 0.05). A qualitative evaluation of root canal preparation was also performed. Results: No statistically significant differences were noted between the groups in the volume of dentine removed after root canal preparation, except for the volume of the coronal third (P < 0.05) and the volume of the apical third (P < 0.05) of the disto-buccal canal of maxillary molars and in the mesial canals of mandibular molars, where ProFile instruments produced significantly less enlarged canal volume in the apical third and more enlarged canal volume in the coronal third (P < 0.05). No statistically significant differences were found in the root canal axis deviation. Conclusions: Under the conditions of this study, both the systems analyzed were able to prepare molar teeth with similar amount of dentine removal and a relatively low risk of procedural errors

Influence of Rotation Speed of Mtwo Files on Root Canal Instrumentation Time with Different Canal Curvatures

Introduction: The aim of this study was to analyze the effect of rotation speed on the instrumentation time of root canals with different curvatures using Mtwo NiTi rotary instruments. Methods and Materials: Forty root canals were selected and divided into 2 groups, according to the angle of curvature (group A&gt;30°, group B&lt;30°). Both groups were divided into 2 subgroups (n=10), according to the rotational speed used for root canal instrumentation (150 rpm: group A1 and B1; 250 rpm: group A2 and B2). The total instrumentation time and the total number of instrumentation cycles (NCI) required to complete root canal preparation were registered for each canal. The mean and standard deviation were then calculated. Data were then statistically analyzed using two-way ANOVA and interaction effect P-values (P&lt;0.05). Results: During root canal instrumentation, there were no file fractures. Total instrumentation time of the low speed groups A1 (150 rpm) and B1 (150 rpm) were significantly higher (P&lt;0.05) than that of the high speed groups, A2 (250 rpm) and B2 (250 rpm); however, there was no statistically significant difference in terms of NCI between the different groups (P&gt;0.05). Statistical difference was not found between the different angles of curvature, group A1 vs B1 and A2 vs B2 in terms of total instrumentation time (P&gt;0.05) and NCI (P&gt;0.05). Conclusions: This ex-vivo study showed that canal preparation with Mtwo rotary files could be completed safely with an increase of the instrumentation time at low rotational speed independently of the root canal curvature