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

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

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

Cartilla socialista-republicana, 1883

El texto retoma las ideas básicas de la Cartilla socialista publicada en 1883. Se desarrolla la teoría serial de Carlos Fourier. el principio de la analogía y el concep­to de democracia. Además, presenta algunas opiniones acerca de la violencia revolucionaria, especialmente la desarrollada por anarquistas, nihilistas y la "Mano Negra" española.  This text borrows the basic ideas of the Socialist Book published in 1861. Charles Fourier's serial theory, the principle of analogy and the concept of democracy are developed. Besides, some opinions on revolutionary violence, particularly the one expressed by the anarchists, the nihilists and the "Mano negra ", are presented

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

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>30°, group B<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<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<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>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>0.05) and NCI (P>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

Efficacy of sonic and ultrasonic irrigation devices in the removal of debris from root canal irregularities in artificial root canals

Objective: to evaluate the efficacy of different sonic and ultrasonic devices in the elimination of debris from canal irregularities in artificial root canals. Materials and Methods: a resin model of a transparent radicular canal filled with dentin debris was used. Five groups were tested, namely: Group 1 - ultrasonic insert 15.02; Group 2 - ultrasonic insert 25/25 IRRI K; Group 3 - ultrasonic insert 25/25 IRRI S; Group 4 - sonic insert 20/28 Eddy on a vibrating sonic air-scaler handpiece; Group 5 - 20.02 K-file inserted on a Safety M4 handpiece. Two different irrigants (5% sodium hypochlorite and 17% EDTA) and 3 different times of activation (20, 40, and 60 seconds) were tested. Means and standard deviations were calculated and statistically analyzed with the Kruskal-Wallis and Wilcoxon tests (p0.05). Conclusions: no significant differences were found between 5% sodium hypochlorite and 17% EDTA. When the time of activation rises, the dentin debris removal increases in all groups. Both sonic and ultrasonic activation demonstrate high capacity for dentin debris removal