“Valores DIAGNOdent en Esmalte Temporal Acondicionado con Láser Er: YAG VS. Autograbado Después de la Disolución Ácida

Se determinaron los valores DIAGNOdent del esmalte de dientes temporales acondicionados con láser Er: YAG vs. autograbado después de la disolución ácidaLas resinas para restauración dental requieren de un acondicionamiento previo del esmalte para una adhesión adecuada, ya sea con ácido, autograbado, y más recientemente con láser. Dentro de las ventajas de la aplicación del láser esta, por una parte la simplificación del procedimiento y por otra la posibilidad de incrementar la resistencia a la disolución ácida. O: Determinar los valores DIAGNOdent del esmalte de dientes temporales acondicionados con láser Er: YAG vs. autograbado después de la disolución ácida. M: Estudio experimental, cuya muestra incluyó 30 piezas dentarias temporales extraídas por razones terapéuticas, divididas aleatoriamente en 3 grupos (n=10); Grupo I Control (sin acondicionamiento), Grupo II Irradiado con láser Er: YAG, Grupo III Autograbado. Después del acondicionamiento, las muestras fueron colocadas en una solución ácida e incubadas, posteriormente se retiraron de la solución, se lavaron, secaron y se procedió al análisis con DIAGNOdent. Para determinar las diferencias entre los grupos se aplicó la prueba de Kruskal-Wallis (p ≤ 0.05). R: El 100% de las muestras del grupo I, III y el 80% del II mostraron valores DIAGNOdent de 0-13, sin diferencias estadísticamente significativas. D: Los reportes en la literatura indican que a pesar de que el acondicionamiento con láser Er: YAG proporciona alta resistencia, provoca un daño considerable a la superficie de los órganos dentales y se considera que la técnica de autograbado es más segura. Sin embargo en el presente estudio aun cuando los datos muestran mayor desmineralización esto únicamente se presenta en un bajo porcentaje de muestras lo cual se puede deber a otros factores. C: Los valores DIAGNOdent del grupo II mostraron en mayor cantidad una ligera desmineralización del esmalte temporal a la disolución ácida, pero no es estadísticamente significativo.Universidad Autónoma del Estado de Méxic

Mechanical, antibacterial and bond strength properties of nano-titanium-enriched glass ionomer cement

The use of nanoparticles (NPs) has become a significant area of research in Dentistry. Objective The aim of this study was to investigate the physical, antibacterial activity and bond strength properties of conventional base, core build and restorative of glass ionomer cement (GIC) compared to GIC supplemented with titanium dioxide (TiO2) nanopowder at 3% and 5% (w/w). Material and Methods Vickers microhardness was estimated with diamond indenter. Compressive and flexural strengths were analyzed in a universal testing machine. Specimens were bonded to enamel and dentine, and tested for shear bond strength in a universal testing machine. Specimens were incubated with S. mutans suspension for evaluating antibacterial activity. Surface analysis of restorative conventional and modified GIC was performed with SEM and EDS. The analyses were carried out with Kolmogorov-Smirnov, ANOVA (post-hoc), Tukey test, Kruskal-Wallis, and Mann Whitney. Results Conventional GIC and GIC modified with TiO2 nanopowder for the base/liner cement and core build showed no differences for mechanical, antibacterial, and shear bond properties (p>;0.05). In contrast, the supplementation of TiO2 NPs to restorative GIC significantly improved Vickers microhardness (

Stability to technological processes of antihypertensive peptides

Trabajo presentado al "EFFoST Annual Meeting: Food Health & Safety" celebrado en Dublin (Irlanda) del 10 al 12 de noviembre de 2010.AGL2007-65035; AGL2008-01713; CENIT-DEV-MET-FUN; CONSOLIDER INGENIO 2010 FUN-C-FOOD CSD 2007-063; P2009/AGR-1469. M. M. Contreras was the recipient of a fellowship of Danone Institute.Peer reviewe

Suicide attempts in mexican teenagers: a cultural consensus theory perspective

El suicidio es un problema de salud pública mundial y los adolescentes son los que presentan con mayor frecuencia esta problemática. El estudio realizado identifica la estructura semántica del dominio cultural, el promedio de conocimiento y el grado de consenso cultural que sobre el suicidio tienen adolescentes con tentativa suicida. El trabajo es un estudio cualitativo mediante la técnica de listas libres. Participaron 29 adolescentes (13 a 18 años). Las listas libres fueron sobre: las causas; los signos y los síntomas; lo que siente, piensa y hace un adolescente antes de cometer suicidio y las estrategias de prevención de éste. Los resultados muestran para cada pregunta un único modelo semántico en el dominio cultural. En lo estructural se identifican los problemas familiares como la causa del intento suicida; la depresión y la tristeza son síntomas previos al intento suicida. La tristeza y la soledad, salir del problema y suicidarse es lo que considera que siente, piensa y hace un adolescente previo al intento de suicidio. Como estrategias de prevención, se identifican le ponga más atención y hablar con él. Los resultados ponderan la importancia de la familia para los programas de prevención de las conductas suicidas en adolescentes. The suicide is a problem of public world health and the adolescents are those who present with more frequency this problem. Nevertheless, the studies of the suicide phenomenon from a cultural perspective are limited. Cultural research in suicidology is important to develop the understanding of the meanings of suicidal behavior in different contexts. The cultural consensus theory would contribute to the cultural perspective of the knowledge of suicidal behaviors in terms of its internal elements and their functioning (emic) and this theory allows knowing if there exists a knowledge shared by a social group regarding an issue and allows to recognize its organization. The aim of this study was to identify the semantic structure of the cultural domain, as well as the average of knowledge and the degree of cultural consensus regarding suicide among adolescent suicide attempters. It was a qualitative study, using the free-listing technique, with a non-random sample made up of 29 adolescents between the ages of 13 and 18 years. The free lists were on: the causes; the signs and the symptoms; what he/she feels, thinks and does before attempting suicide and the strategies of suicide prevention at adolescence. The results showed for every question a single semantic model in the cultural domain suicide attempt. In such structure, the family problems were identified as the cause of suicidal attempt; the depression and the sadness were symptoms before suicidal attempt. The sadness, the loneliness and the anger were what an adolescent feels before the suicide attempt. Furthermore, to get out of the problem and to end his/her life were what an adolescent thinks before attempting suicide and to commit suicide was what an adolescent does before to suicide attempt. To pay more attention, to talk with the adolescent, to improve the communication with the parents and to attend a psychotherapy were identified as strategies for suicide prevention. The results highlight the importance of the family of suicide prevention programs for adolescents based on cultural knowledge.ITESO, A.C.Universidad de GuadalajaraInstituto Mexicano del Seguro SocialPsicólogos Especializados Jalisc

Evaluation of Self-Etching Adhesive and Er:YAG Laser Conditioning on the Shear Bond Strength of Orthodontic Brackets

The purpose of this study was to evaluate the shear bond strength, the adhesive remnant index scores, and etch surface of teeth prepared for orthodontic bracket bonding with self-etching primer and Er:YAG laser conditioning. One hundred and twenty bovine incisors were randomly divided into four groups. In Group I (Control), the teeth were conditioned with 35% phosphoric acid for 15 seconds. In Group II the teeth were conditioned with Transbond Plus SEP (5 sec); III and IV were irradiated with the Er:YAG 150 mJ (11.0 J/cm2), 150 mJ (19.1 J/cm2), respectively, at 7–12 Hz with water spray. After surface preparation, upper central incisor stainless steel brackets were bonded with Transbond Plus Color Change Adhesive. The teeth were stored in water at 37°C for 24 hours and shear bond strengths were measured, and adhesive remnant index (ARI) was determined. The conditioned surface was observed under a scanning electron microscope. One-way ANOVA and chi-square test were used. Group I showed the significantly highest values of bond strength with a mean value of 8.2 megapascals (MPa). The lesser amount of adhesive remnant was found in Group III. The results of this study suggest that Er:YAG laser irradiation could not be an option for enamel conditioning