Evaluation of the filling ability of artificial lateral canals using calcium silicate-based and epoxy resin-based endodontic sealers and two gutta-percha filling techniques.

AIM: To evaluate the ability of a calcium silicate-based sealer (iRoot SP) and an epoxy resin-based sealer (Topseal) using two gutta-percha filling techniques to fill artificial lateral canals (ALCs). METHODOLOGY: Seventy single-rooted human teeth were selected. Ten of these were used to obtain pilot data. Three ALCs were produced on mesial and distal surfaces of each root, one in each third, using size 10 engine reamers. The roots were randomly assigned to four experimental groups according to the filling technique and sealer used: 1, cold gutta-percha (single-point technique) with iRoot SP (SP-iR); 2, cold gutta-percha (single-point technique) with Topseal (SP-T); 3, continuous wave of condensation technique with iRoot SP (CWC-iR); and 4, continuous wave of condensation technique with Topseal (CWC-T). Digital periapical radiographs were taken. After the sealer had set, the roots were demineralized, cleared in methyl-salicylate and examined under a stereomicroscope. The depth of penetration of sealer and/or gutta-percha into the ALC was scored using a 5-point system, conducting an analysis on four surfaces. Filling scores of 0-1 were considered not acceptable, whilst scores of 2-4 were considered acceptable. Pearson's chi-square test was used to compare the experimental groups (P < 0.05). RESULTS: CWC-T was associated with the highest acceptable filling (57.8%), followed by CWC-iR (53.3%), SP-T (48.9%) and SP-iR (36.7%). Only when SP-iR was compared to the other groups, was the difference significant (P < 0.05). The apical third was associated with the lowest acceptable filling (37.5%). It was followed, in ascending order, by the middle (51.6%) and coronal thirds (58.3%). These differences were significant only when the apical thirds were compared to the other root thirds (P < 0.05). CONCLUSION: The calcium silicate-based sealer with continuous wave of condensation was more effective in artificial filling lateral canals than the single-point technique. The epoxy resin-based sealer with both filling techniques was effective in artificial filling lateral canals.

Asociación genotipo-fenotipo en la fibrosis quistica análisis de la mutación DF508 en población Colombiana / Association between genotipe-fenotipe in cystic fibrosis, análisis of mutation DF508 in Colombian population

Se estudiaron 35 pacientes con diagnóstico confirmado de fibrosis quística (clínica y laboratorio) hasta Diciembre de 1994, las características de estos pacientes fueron: sexo masculino 22 (6208) femenino 13 (37.2) con una edad promedio de 7.2 años (4.9-904); 60 nacidos en cundinamarca y el resto de diferentes zonas del país. Ancestros de estos pacientes nacidos en cundinamarca 41.4 y en menor proporción de Boyacá, Antioquia y Caldas. Todos eran mestizos de origen hispano. Se investigo la presencia del alelo DF508 en los 70 cromosomas analizados fué del 50, 12 (34) en forma homocigotica, 11 (32) en forma heterocigotica y 12 (34) no portaban dicha mutación. No se encontraron diferencias significativas, entre los genotipos (DF508/DF508-DF508/No.-DF508), en cuanto a edad de inicio de síntomas, presencia de síntomas iniciales, edad de diagnóstico de la enfermedad , edad al momento de ingresar al estudio, presencia de insuficiencia pancreatica, existencia de complicaciones de FQ, compromiso clínico por store de Brasfield. De igual forma no se encontró relación entre ser portador de la mutación DF508 y el lugar geográfico de nacimiento.La ausencia de asociación entre la severidad de la enfermedad y el genotipo en esta población mestiza hispana, puede reflejar la presencia de mutaciones más severas no detectadas en nuestra muestra o el efecto modificante de genes en otro loci no FQ.