Resumo: Descreve-se neste artigo a presença mediada por dispositivos de imagem. O recorte proposto situa a cena contemporânea intermedial, emergindo como estudo de destaque o espetáculo imersivo Rouge Mékong, desenvolvido pelo coletivo canadense de artistas interdisciplinares, Collectif Lebovitz. A referida experiência nos guiará como obra sistematizadora do conceito efeito de presença, desenvolvido por Josette Féral, e aqui investigado como constituinte da dramaturgia desse espetáculo. Investiga-se ainda a apresentação de discussões voltadas para a presença do ator mediada pela tecnologia da imagem virtual e as possibilidades de percepção sobre o espectador levantadas por Auslander (2008), Féral (2012) e Lehmann (2007) quando em relação à cena intermedial.

Abstract: In this paper it is described the presence mediated by imaging devices. It is focused on the contemporary intermedial scene, emerging as the highlighted study Rouge Mékong, an immersive spectacle developed by Collectif Lebovitz, a Canadian interdisciplinary collective of artists. This experience will guide us as a systematization of the presence effect concept, developed by Josette Féral, and investigated here as a constituent of the dramaturgy of this spectacle. It is also investigated the presentation of discussions focused on the presence of the actor mediated by virtual image technology and the expectations of perception on the audience raised by Auslander (2008), Féral (2012) and Lehmann (2007) when in relation to the intermedial scene.

Résumé: Nous avons l’intention de discuter dans cet article les dispositifs d’image et la présence médiée par eux. Notre accent est mis sur la scène contemporaine intermédiale, émergeant comme étude de premier plan le spectacle immersif Rouge Mékong développé par le collectif Canadien des artistes interdisciplinaires, Collectif Lebovitz. Cette expérience va nous guider comme une œuvre de systématisation du concept effet de présence développé par Josette Feral, étudié ici en tant que constituant de la dramaturgie de ce spectacle. On y étudie encore la présentation de discussions tournées vers la présence de l’acteur associé à la médiation par la technologie de l’image virtuelle et les attentes de perception de l’audience soulevées par Auslander (2008), Féral (2012) et Lehmann (2007) en ce qui concerne la scène intermédiale.

OBJECTIVES: Although individuals with Down syndrome have considerable oral disease, the prevalence of dental caries in this group is low. The present study aimed to compare known risk factors for dental caries development in children with Down syndrome and a matched population (siblings). In both populations, the number of acidogenic microorganisms, such as mutans streptococci, lactobacilli and Candida species, and the paraffin-stimulated pH, flow rate and IgA concentration in whole saliva were evaluated and compared. METHOD: Saliva was collected, and the caries index was evaluated in 45 sibling pairs aged between 6 and 18 years old. The salivary IgA concentration was determined by immunoturbidimetry. Salivary mutans streptococci, lactobacilli and Candida species were quantified on mitis salivarius agar containing bacitracin and 20% sucrose, rogosa agar supplemented with glacial acetic acid and sabouraud agar supplemented with chloramphenicol, respectively. RESULTS: Down syndrome children had a higher caries-free rate (p<0.05) and lower salivary mutans streptococci counts (p<0.03) compared to their siblings. Similar numbers of lactobacilli and Candida species were found in both groups. Salivary flow rates were 36% lower in Down syndrome children compared to their siblings (p<0.05). The salivary pH did not differ between Down syndrome children and controls. The Down syndrome children had an IgA secretion rate 29% lower than that of their siblings, but this difference was not statistically significant. CONCLUSIONS: In conclusion, the lower number of mutans streptococci in the saliva may be one of the factors contributing to the lower caries rate observed in Down syndrome children, despite evidence of hyposalivation.

OBJECTIVES: Oral health in Down syndrome children has some peculiar aspects that must be considered in the follow-up of these patients. This study focuses on characterizing the environmental and host factors associated with dental caries in Portuguese children with and without Down syndrome. METHODS: A sibling-matched, population-based, cross-sectional survey was performed. RESULTS: Down syndrome children presented a significantly greater percentage of children without caries, 78% vs. 58% of non-Down syndrome siblings. This difference in the DMFT index (number of decayed, missing and filled teeth) essentially reflects data obtained from treated teeth, for which 91% of children with Down syndrome had never had a tooth treated vs. 67% of siblings. This result was statistically significant, whereas results for decayed and lost teeth did not differ between Down syndrome children and their unaffected siblings. Additionally, in Down syndrome children, a delayed eruption of the second molar occurs. Down syndrome children and their siblings have similar oral hygiene habits, but a higher percentage of Down syndrome children visit a dentist before the age of three years, in comparison to their siblings. Bruxism was also more common in Down syndrome children compared to their siblings. CONCLUSIONS: Our results show that Portuguese children with Down syndrome have lower caries rates than children without Down syndrome. This reduced prevalence may be associated with the parents' greater concern about oral health care in Down syndrome children, resulting in their taking them sooner to visit a dentist, as well as to a higher bruxism prevalence and delayed tooth eruption.