Variaciones histórico-culturales de la estética dental / Historical and cultural variations of teeth aesthetics

Resumen La estética dentaria es un tema de amplia relevancia en la odontología actual, tanto en el ambiente universitario como en la práctica privada. Cuando las personas expresan que desean una sonrisa más hermosa, dentistas y pacientes piensan automáticamente en aclarar el color de los dientes como un componente importante de este proceso. ¿Cuál es la razón de esta concordancia tácita? Algunos podrían argüir que una sonrisa saludable es naturalmente más blanca, pero sabemos que la funcionalidad fisiológica no necesariamente está asociada a una estética socialmente determinada. Es más, muchas veces los procedimientos estéticos implican modificaciones corporales que no necesariamente son naturales, ni saludables. El objetivo de esta revisión, es brindar elementos de discusión acerca de aspectos históricos y culturales relacionados con el posicionamiento del color dentario como parte importante de un ideal estético. Se pretende argumentar, que el deseo de tener dientes más blancos reside eminentemente en influencias culturales. Asimismo, se invita a la reflexión de que, si los "dientes blancos" debiesen ser equiparados a "dientes saludables", con las consecuentes ramificaciones que implicaría esta suposición, en nuestro mundo profesional.

Abstract Dental aesthetics is a topic of wide relevance in current dentistry, both in dental education and in private practice. When people express that they want a beautiful smile, both dentists and patients think of whitening tooth color. What is the reason for this tacit agreement? Some might argue that a healthy smile is naturally whiter, but we know that physiological functionality is not always associated with socially determined aesthetics. Furthermore, some aesthetics procedures might involve body modifications that are not necessarily natural nor healthy. The aim of this review is to to provide elements of discussion about historical and cultural aspects related to the positioning of tooth color as an important part of an aesthetic ideal. To argue that the desire for whiter teeth resides in cultural influences. To invite reflection if "white teeth" should be equated with "healthy teeth", with the consequences this assumption would imply in our professional field.

Perception of Causes of Repetition Amongst Dentistry Students A Novel Experience with Content Analysis

ABSTRACT: To determine the perception of fourth-year dentistry students at a private Chilean university, regarding the causes of their course repetition. Open-ended questions were asked to 14 repeating students. The resulting narratives went through content analysis using QDA Miner Lite software. The category "non-fullfilment with clinical requirements" had the highest frequency of appearance (52.0 %). Codes with the highest frequency of appearance were "Lacked of time" (24.0%); "Lack of proper organization of time/patient's agenda" (18.0 %) and "Lack of knowledge of the clinical dynamics" (16.0%). The tardiness and repeated absences of the patients were mentioned as the greatest difficulty faced by the students (18.0 %). Students perceive the reasons behind their repetition, differently. However aspects associated with compliance of clinical requirements and patients management are recurring issues. Content analysis is a useful tool for acquiring and analyzing data of complex phenomena as perspectives on university repetition among higher-level dentistry students.

RESUMEN: El objetivo del estudio fue determinar la percepción de los estudiantes de cuarto año de odontología en una universidad chilena, con respecto a las causas de su repetición académica. Se realizaron preguntas abiertas a 14 estudiantes repitentes del cuarto año de la carrera de Odontología. Se desarrolló el análisis de contenido de los relatos de los participantes con el software QDA Miner Lite. La categoría "incumplimiento de requisitos clínicos" obtuvo la mayor frecuencia de aparición entre los relatos (52.0 %). Los códigos con mayor frecuencia de aparición son "faltó tiempo" (24.0 %); "mal manejo y organización de mi tiempo y el del paciente" (18.0 %) y "faltó conocimiento de la dinámica de la asignatura" (16.0 %). Como anexo, la impuntualidad y ausencias reiteradas de los pacientes, fueron mencionadas como la mayor dificultad enfrentada por los estudiantes (18.0 %). Los estudiantes perciben de manera heterogénea las razones detrás de su repetición académica, sin embargo aspectos asociados al cumplimiento de los requisitos clínicos y el trato con los pacientes, son reiterativos en los relatos. El análisis de contenido es una herramienta útil para adquirir y analizar fenómenos complejos, tal como la percepción sobre la repetición universitaria en años superiores de Odontología.

Non-Random Distribution and Ecophysiological Differentiation of Pyropia Species (Bangiales, Rhodophyta) Through Environmental Gradients.

Recently 18 Bangiales seaweed species were reported for the Chilean coast, including Pyropia orbicularis and Pyropia variabilis (large [LM] and green [GM] morphotypes). Porphyra/Pyropia spp. occur mainly in the upper intertidal where desiccation stress is triggered by tidal fluctuations. However, the influence of environmental and ecophysiological variables and seasonal differences on Porphyra/Pyropia (microhabitats) intertidal distributions is unknown. Accordingly, we determined (i) the effect of environmental variables (temperature [T], relative humidity [RH], and photosynthetically active radiation [PAR]) and season on distribution, and (ii) physiological (cellular activity and lipid peroxidation [LPX]) and molecular responses (antioxidant enzymes expression at biochemical and transcript level) to desiccation stress in both Pyropia species and morphotypes (common garden experiment, on flat rocky platforms). Multivariate analyses of coverage and abundance in relation to environmental variables revealed a significant effect of temperature on P. variabilis GM distribution, GM dominating almost exclusively on rocky walls (where lowest PAR and T values but maximum RH were registered). Conversely, Pyropia orbicularis and Pyropia variabilis LM were found in high abundance on flat rocky platforms in summer, LM and GM also dominating flat rocky platforms in winter and spring. LPX and catalase activity did not differed among species in summer, while in winter activity and transcription of cat were higher in P. orbicularis than P. variabilis. Results suggest that tolerance to environmental stresses such as temperature could regulate the occurrence of P. variabilis GM on rocky walls; conversely, abundances of P. variabilis and P. orbicularis on flat rocky platforms would be also regulated by other abiotic and/or biotic factors.