RESUMO
El objetivo de este trabajo fue evaluar el efecto de soluciones de irrigación endodónticas solas y combinadas sobre iones calcio y fosfato de la dentina radicular ex vivo. Se emplearon 56 discos de dentina obtenidos del tercio medio radicular de premolares inferiores unirradiculares extraídos por razones ortodóncicas. Los discos se dividieron al azar en 8 grupos (n=7). Grupo I: agua destilada (AD), Grupo II: hipoclorito de sodio (NaClO) 1 %, Grupo III: EDTA 17 %, Grupo IV: ácido maleico (AM) 5 %, Grupo V: ácido acético (AA) 5 %, Grupo VI: EDTA 17 % + NaClO 1 %, Grupo VII: AM 5 % + NaClO 1 %, Grupo VIII: AA 5 % + NaClO 1 %. Los segmentos de dentina permanecieron en contacto a 37° C durante 5 min y 2,5 minutos en cada solución cuando se usaron en forma sucesiva. Se determinó la concentración de iones calcio de las soluciones mediante espectrometría de absorción atómica y la concentración de iones fosfatos mediante colorimetría (Wienner Lab.). Los resultados se expresaron en mg/ml/gr de tejido. Para el análisis estadístico se utilizó ANOVA y Test de Tukey. AA 5 % y EDTA 17 % se comportaron de manera similar utilizados solos durante 5 minutos, NaClO 1 % no mostró diferencias con el AD. AM 5 % eliminó significativamente más calcio y fosfato que todos los grupos. Todas las soluciones desmineralizaron la dentina, pero AM 5 % durante 5 min fue la solución que más afectó el componente inorgánico de la dentina.
The aim of the present study was to evaluate ex vivo irrigating solutions effect under calcium and phosphates dentin ions, using them alone and combined. In this study 56 dentin discs where used. They were obtained from middle third of mandibular single-root premolars extracted for orthodontics reasons. Discs were randomly divided into 8 groups (n:7). Group I: Distilled water (DW), Group II: 1 % sodium hypochlorite (NaOCl), Group III: 17 % EDTA, Group IV: 5 % maleic acid (MA), Group V: 5 % acetic acid (AA), Group VI: 17 % EDTA + 1 % NaOCl, Group VII: 5 % MA + 1 % NaOCl, Group VIII: 5 % AA + 1 % NaOCl. Dentin segments were kept in contact with irrigating solutions at 37°C for 5 minutes, when used alone, or for 2.5 minutes when used combined. After that, calcium ions (using absorption atomic spectrometry) and phosphorus ions (by colorimetry Wienner Lab.) were determined. Results were expressed in mg/ml/g tissue. Statistical analysis was performed by ANOVA and Tukey test. 5 % AA and 17 % EDTA eliminated similar concentrations of calcium and phosphates ions from dentin at 5 minutes exposure time, while 1 % NaOCl did not present statistical differences with control. 5 % MA eliminated significantly more calcium and phosphates ions than the rest of analyzed groups. Every tested solutions demineralized human dentin, but 5 % MA used for 5 minutes did it the most.
RESUMO
In order to know the current condition of the Echinometra lucunter population in the Colombian Caribbean, ten zones of the most representative rocky-shore were selected for sampling between November 2002 and May 2003. In each zone, four transects of 10.25 m2 were located parallel to the coast, and measured with a 0.25 m2 quadrant under the tide level. Two subsamples of 0.01 m2 were chosen from each quadrant, in order to determine the sea urchin heights and its associated fauna. This species was found in nine of the selected zones where the rocky-shore was of sedimentary origin and was absent in Punta Gloria because of the igneous origin of the rock, that the sea urchins cannot bore. The greatest average densities were obtained in Zapsurro and Inca Inca with 69 and 65 ind/m2 respectively; these are high values for the Caribbean Sea, whereas Acandi and Punta Betin had the lowest because of continental water discharges. The most frequent test diameter was between 25 and 40 mm (smaller on the western zones). The density of E. lucunter and of its associated fauna (including the endemic Ophiothrix synoecina) in the Santa Marta area decreased in the last decade