ABSTRACT
@#Studies on parasite populations in Antarctic soils are scarce and thus little is known about the threat of these parasites towards either the natural fauna or human visitors. However, human presence in Antarctica, mainly through research and tourism, keeps increasing over time, potentially exposing visitors to zoonotic infections from Antarctic wildlife and environment. Most available literature to date has focused on faecal samples from Antarctic vertebrates. Therefore, this study addressed the possible presence of parasites in Antarctic soil that may be infectious to humans. Soil samples were obtained from five locations on Signy Island (South Orkney Islands, maritime Antarctic), namely North Point and Gourlay Peninsula (penguin rookeries), Pumphouse (relic coal-powered pump house), Jane Col (barren high altitude fellfield) and Berntsen Point (low altitude vegetated fellfield close to current research station). Approximately 10% of the soil samples (14/135) from 3 out of the 5 study sites had parasites which included Diphyllobotridae spp. eggs, Cryptosporidium sp., an apicomplexan protozoa (gregarine), Toxoplasma gondii, helminths (a cestode, Tetrabothrius sp., and a nematode larva) and mites. The presence of parasites in the 3 sites are most likely due to the presence of animal and human activities as two of these sites are penguin rookeries (North Point and Gourlay Peninsula) while the third site (Pumphouse Lake) has human activity. While some of the parasite species found in the soil samples appear to be distinctive, there were also parasites such as Cryptosporidium and Toxoplasma gondii that have a global distribution and are potentially pathogenic.
ABSTRACT
Toda función del sistema estomatognático involucra la acción sinérgica de la musculatura paraprotética, representada por estructuras complejas tales como lengua, labios, mejillas y piso de boca. Al rehabilitar a través de prótesis completas no siempre se considera la influencia de la dinámica muscular, y menos aún cuando alguna de estas estructuras presenten alguna patología, por ejemplo, el compromiso del nervio facial que genera espasmos musculares involuntarios. En tal situación, la ubicación de los dientes y la forma de las superficies pulidas pueden llegar a ser decisivos entre éxito o fracaso de la rehabilitación. Se sabe que los implantes oseointegrados proveen retención, soporte y estabilidad, sin embargo existen situaciones especiales en que no es posible acceder a este tipo de tratamiento, tanto por razones médico quirúrgicas o costos asociados. En este estudio se ha utilizado un registro Piezográfico de la Zona Neutra en un paciente con compromiso del nervio facial que genera espasmos musculares involuntarios del lado afectado, obteniéndose una rehabilitación protésica basada en la apropiada relación entre superficie protésica externa y tejidos circundantes, mejorando requisitos funcionales tales como retención y estabilidad. Se ha utilizado el sistema de tomografía computarizada Cone Beam, con el objetivo de evidenciar el registro piezográfico. Los resultados obtenidos con estas prótesis piezográficas demuestran ser superior en factores como comodidad y fonoarticulación pero inferior en eficiencia masticatoria comparada con la técnica convencional.
Every function of the stomatognathic system involves the synergistic action of the musculature around the prosthesis, consisting of complex and individual structures such as tongue, lips, cheeks and mouth floor. When planning and making complete prostheses, the muscular dynamic is not always considered. This can generate instability of the device during function, the location of the artificial teeth is made arbitrarily on the top and middle parts of the flange, and the configuration of the polished areas is made according to mechanistic concepts. This factor takes more relevance in patients with severe atrophy of their residual flanges, where the prosthetic stability can be a decisive factor between the success or failure of the rehabilitation. It is known that the osseointegrated implants provide retention, support and stability. However, there are special situations in which it is not possible to access to this type of treatment, both for medical surgical reasons or associated costs. In this study, a Piezographyc record of the Neutral Zone was used in a patient with facial nerve involvement generating involuntary muscle spasms of the affected side. A prosthetic rehabilitation based on the appropriate relation between external prosthetic surface and surrounding tissues was obtained, improving functional requirements such as retention and stability. The computerized tomographic Cone Beam system was used, with the objective to show the piezographic record. The results obtained with these piezographic prostheses prove to be superior in factors like comfort and speech articulation, but inferior in masticatory efficiency, where the conventional technique is still better.