Evaluación in vivo de la sustantividad de la clorhexidina al 0,2% en diferentes ecosistemas orales

La placa dental se considera un modelo especializado de biofilm microbiano, que se forma sobre todos los tejidos intraorales duros y blandos, y representa el principal agente etiológico de la caries y de la enfermedad periodontal. La idea de aplicar un antiséptico oral con fines profilácticos exige analizar su eficacia antimicrobiana en diferentes ecosistemas orales, particularmente en los que presentan características estructurales y fisiológicas diferentes a la saliva, como es el caso de la placa dental. El estudio in vivo de la actividad antibacteriana de un antiséptico supone el análisis de su efecto inmediato y de su sustantividad. Se ha demostrado que la clorhexidina tiene un efecto antibacteriano inmediato y una mayor sustantividad in vivo que otros antisépticos empleados en la cavidad oral. En la mayoría de las series publicadas, la cuantificación de la actividad antimicrobiana de la clorhexidina en saliva se realizó empleando técnicas microbiológicas de cultivo en placa. Sin embargo, algunos autores cuestionaron la fiabilidad de estas técnicas y, como alternativa, propusieron el uso de ensayos fluorescentes que utilizan fluorocromos específicos para marcar bacterias viables y no viables, en base a la integridad de su membrana citoplasmática

Induced martensitic transformation during tensile test in nanostructured bainitic steels

Retained austenite in nanostructured bainite is able to undergo mechanically induced martensitic transformation. However, the link between transformation and deformation mechanisms involved makes difficult the understanding of the process. In this work, a model has been developed to assess the effect of the external stress itself on the martensite phase transformation. In addition, after a detailed initial microstructural characterization, the martensite fraction evolution during tensile deformation has been obtained by means of X-ray diffraction analyses after interrupted tensile tests in several nanostructured bainitic steels. Experimental results have been compared to the outputs of the model, as a reference. They suggests that stress partitioning between phases upon tensile deformation is promoted by isothermal transformation at lower temperatures.The authors gratefully acknowledge the support of the European Research Fund for Coal and Steel, the Spanish Ministry of Economy and Competitiveness and the Fondo Europeo de Desarrollo Regional (FEDER) for partially funding this research under the contracts RFSR-CT-2012-00017, RFSR-CT-2014-00016 and MAT2013-47460-C5-1−P respectively. LM-R also acknowledges this same Ministry for financial support with ref. FPI: BES-2011-044186.Peer Reviewe

Modelos de enseñanza-aprendizaje. Un modelo de aplicación del Aprendizaje Basado en Problemas (ABP) en odontología infantil

Entre las diferentes técnicas de Enseñanza-Aprendizaje utilizadas en las ciencias biomédicas, una de las que mayor popularidad ha adquirido en las últimas décadas es el “Aprendizaje Basado en Problemas” (ABP), considerado un hito en la educación médica. Como ocurre en otros sistemas, el ABP está centrado en el alumno y pretende fomentar un tipo de aprendizaje auto-dirigido. De sus principales virtudes se destaca que favorece el desarrollo de cierto tipo de competencias como la toma de decisiones, el razonamiento crítico, o el trabajo en equipo. Buena parte del el éxito de una actividad basada en el ABP radica en la planificación de la misma. Los principales factores que deben tenerse en cuenta y detallar son: - la delimitación de los objetivos a alcanzar - la selección del/los problemas sobre los que se trabajará - la definición de las reglas de la actividad - determinar el tiempo en el que deberá darse solución al problema A lo largo del siguiente capítulo se detallan cada uno de estos aspectos y se relata una modelo de experiencia educativa inspirada en el ABP. El objetivo de la actividad es poner al alumno frente a situaciones clínicas infrecuentes en la consulta de Odontología Infantil en la Licenciatura/Grado de Odontología pero que son situaciones relativamente cotidianas para un odontólogo general/odontopediatra. Se pretende fomentar la integración de conocimientos de odontología infantil, la responsabilidad colectiva y la toma de decisiones clínicas simulando las condiciones a las que los alumnos se van a enfrentar una vez graduados. Para ello se diseñaron una serie de situaciones clínicas en un paciente virtual. A lo largo de todo el curso académico se realizaron distintas sesiones en las que se facilitaba a los alumnos una serie de datos clínicos (historia clínica, fotos, radiografías) y se les planteaban una serie de preguntas: diagnóstico, plan de tratamiento justificado, etc. que deberían responder en 15 minutos. Los alumnos participaron por equipos en base a los boxes en los que realizaban sus prácticas clínicas pero sólo uno del equipo respondía a las preguntas en cada jornada. A medida que transcurrían las diferentes sesiones clínicas se fue haciendo pública las respectivas calificaciones y el acumulado hasta ese momento de forma que los alumnos podían ir viendo sus progresos en relación al resto de la clase. Para fomentar la implicación en la actividad se estableció un “pódium” con los boxes que obtuvieron una mejor puntuación al acabar el curso académico, que además vieron recompensado su buen hacer con un incremento en su calificación final en la asignatura. La opinión de los alumnos respecto a la actividad fue muy positiva, y un buen complemento para la formación teórico-práctica recibida respecto a Odontología Infantil

Propiedades psicométricas de la Escala de Asertividad Sexual: SAS en universitarios de Chimbote

El estudio de diseño instrumental, concibió determinar las evidencias psicométricas de la escala de Asertividad sexual (SAS), en una muestra aleatoria de 384 participantes, de ambos sexos, de 16 a 40 años de edad, que cursan estudios de formación profesional dentro de cuatro universidades de Chimbote. Los resultados en la validez basada en la estructura interna por el análisis factorial confirmatorio, reporta índices de ajuste absoluto χ2/gl=4.25, AGFI=.978, RMSEA=.052, asimismo índices de ajuste comparativo TLI=.953, CFI=.912, además de cargas factoriales estandarizadas de .25 a .97, y covarianzas de .85 a .88, como segunda propiedad, la confiabilidad de las puntuaciones se obtuvo mediante el método de consistencia interna con el reporte del coeficiente omega corregido, para los factores, Iniciativa se obtuvo un valor de .72, en Rechazo de .71, y para Embarazo-ETS de .79, de aporte metodológico-teórico-práctico

Pseudoepitheliomatous hyperplasia after diode laser oral surgery: an experimen tal study

Background : To examine the process of epithelial reparation in a surgical wound caused by diode laser. Material and Methods : A n experimental study with 27 Sprage-Dawley rats was undertaken. The animals were randomly allocated to two experimental groups, whose individuals underwent glossectomy by means of a diode laser at different wattages, and a control group treated using a number 15 scalpel blade. The animals were slaughtered at the 2nd, 7th, and 14th day after glossectomy. The specimens were independently studied by two pathologists (blinded for the specimens’ group). Results: At the 7th day, re-epithelisation was slightly faster for the control group (conventional scalpel) ( p =0.011). At the 14th day, complete re-epithelization was observed for all groups. The experimental groups displayed a pseudoepitheliomatous hyperplasia. Conclusions: It is concluded that, considering the limitations of this kind of experimental studies, early re-epithelisation occurs slightly faster when a conventional scalpel is used for incision, although re-epithelisation is completed in two weeks no matter the instrument used. In addition, pseudoepitheliomatous hyperplasia is a potential event after oral mucosa surgery with diode laser. Knowledge about this phenomenon (not previously described) may prevent diagnostic mistakes and inadequate treatment approaches, particularly when dealing with potentially malignant oral lesions

Biomarkers in ocular chronic graft versus host disease: tear cytokine- and chemokine-based predictive model.

Producción CientíficaPurpose: To develop a tear molecule level-based predictive model based on a panel of tear cytokines and their correlation with clinical features in ocular chronic graft versus host disease (cGVHD). Methods: Twenty-two ocular cGVHD patients and 21 healthy subjects were evaluated in a controlled environmental research laboratory (CERLab). Clinical parameters were recorded, and tears were collected. Levels of 15 molecules (epidermal growth factor [EGF], IL receptor antagonist [IL-1Ra], IL-1β, IL-2, IL-6, IL-8/CXCL8, IL-10, IL-12p70, IL-17A, interferon inducible protein [IP]-10/CXCL10, IFN-γ, VEGF, TNF-α, eotaxin 1, and regulated on activation normal T cell expressed and secreted [RANTES]) were measured by multiplex-bead assay and correlated with clinical parameters. Logistic regression was used to develop a predictive model. Leave-one-out cross-validation was applied. Classification capacity was evaluated in a cohort of individuals with dry eye (DE) of other etiologies different from GVHD. Results: Epidermal growth factor and IP-10/CXCL10 levels were significantly decreased in ocular cGVHD, positively correlating with tear production and stability and negatively correlating with symptoms, hyperemia, and vital staining. Interleukin-1Ra, IL-8/CXCL8, and IL-10 were significantly increased in ocular cGVHD, and the first two correlated positively with symptoms, hyperemia, and ocular surface integrity while negatively correlating with tear production and stability. Predictive models were generated, and the best panel was based on IL-8/CXCL8 and IP-10/CXCL10 tear levels along with age and sex, with an area under the receiving operating curve of 0.9004, sensitivity of 86.36%, and specificity of 95.24%. Conclusions: A predictive model based on tear levels of IL-8/CXCL8 and IP-10/CXCL10 resulted in optimal sensitivity and specificity. These results add further knowledge to the search for potential biomarkers in this devastating ocular inflammatory disease.Ministry of Economy and Competitiveness, Madrid, Spain, SAF-2010 15631 (AES)

Antibiotic Prophylactic Regimens for Infective Endocarditis in Patients Undergoing Dental Procedures

Up to date causal relationship has been demonstrated between dental manipulations and the onset of infective endocarditis (IE). However, since 1955, numerous expert committees have proposed antibiotic prophylaxis (AP) to prevent bacteraemia of oral origin. Controversy regarding the efficacy of AP prior to the dental procedures has intensified in recent years because of the lack of conclusive evidence on its efficacy for the prevention of IE and on its cost-effectiveness, as well as the possibility of allergic reactions and the emergence of antibiotic resistance. Accordingly, AP is now maintained exclusively for patients at highest risk and who require the manipulation of the gingival or periapical regions of the teeth or perforation of the oral mucosa. In the context of a restrictive policy, the National Institute for Health and Clinical Excellence (NICE) of the United Kingdom published a new guideline in 2008 stating that “AP against IE is not recommended for persons undergoing dental procedures”, regardless of risk status and of the nature of the procedure to be performed. The NICE guideline has generated further controversy, and expert committees in other countries continue to publish prophylactic regimens for the prevention of IE secondary to dental procedures. In this chapter, we discuss the principal guidelines currently applicable in Europe, the USA and Australia, and we draw particular attention to the need for randomised clinical trials

Oral mucosal peeling related to dentifrices and mouthwashes : a systematic review

The aim of this systematic review was to summarise the clinical information available about oral mucosal peeling (OMP) and to explore its aetiopathogenic association with dentifrices and mouthwashes. PICOS outline: Population: subjects diagnosed clinically and/or pathologically. Intervention: exposition to oral hygiene products. Comparisons: patients using products at different concentrations. Outcomes: clinicopathological outcomes (primary) and oral epithelial desquamation (secondary) after use. Study design: any. Exclusion criteria: reports on secondary or unpublished data, in vitro studies. Data were independently extracted by two reviewers. Fifteen reports were selected from 410 identified. Descriptive studies mainly showed low bias risk, experimental studies mostly an ?unclear risk?. Dentifrices or mouthwashes were linked to OMP, with an unknown origin in 5 subjects. Sodium lauryl-sulphate (SLS) was behind this disorder in 21 subjects, tartar-control dentifrices in 2, and flavouring agents in 1 case. Desquamation extension was linked to SLS concentration. Most cases were painless, leaving normal mucosa after desquamation. Tartar-control dentifrices caused ulcerations more frequently. OMP management should consider differential diagnosis with oral desquamative lesions, particularly desquamative gingivitis, with a guided clinical interview together with pathological confirmation while discouraging the use of the product responsible for OMP

In Vivo Antiplaque Effect of Three Edible Toothpastes

Objectives: The objective of this study was to analyse the antibacterial and antiplaque activity of three edible toothpastes with the widest worldwide distribution: KidScents™, which contains essential oils; Browning B&B™,, with medicinal plants; and Wysong Probiodent™, which contains probiotics. Study Design: The study group was formed of twenty healthy volunteers (dental students) with a good oral health status. Using a balanced randomisation system, all volunteers performed toothbrushing with four products (the three edible toothpastes and water) at intervals of one week. Bacterial vitality in the saliva was analysed by epifluorescence microscopy and plaque regrowth was evaluated using the Turesky-Quigley-Hein plaque index. Results: Bacterial vitality in the saliva was significantly higher after toothbrushing with water (positive control) than with the three toothpastes (P=0.002, P=0.003 and P<0.001, respectively). The plaque index was significantly higher after using these three toothpastes than after toothbrushing with water (P=0.047, P=0.032 and P<0.001, respectively). Conclusions: The three edible toothpastes analysed have some antimicrobial activity but favour plaque regrowth