ABSTRACT
El propósito de este estudio fue comparar la exactitud dimensional de tres materiales de impresión con y sin aplicación de adhesivo. Los materiales utilizados fueron: silicona de condensación Oranwash L, Zetaplus (Zhermack), silicona de adición Elite H-D (Zhermack®) y poliéter ImpregumÕ Soft (3M ESPE). Se confeccionó un modelo maestro de acero inoxidable, el cual simulaba una hemi- arcada con preparaciones para prótesis fija. Por cada material se realizaron 20 impresiones, a 10 se les aplicó adhesivo a la cubeta. Se tomaron siete medidas a los modelos de yeso obtenidos de éstas impresiones mediante una máquina de medición por coordenadas Beyond 700 /900 Mitutoyo Corporation®, para ser comparadas con las medidas del modelo maestro. Se encontraron diferencias estadísticamente significativas con y sin aplicación de adhesivo para la silicona de condensación en la medida de la distancia bucolingual del pilar 1 (M7) y para la silicona de adición en la medida entre pilares (M6), mientras que para el poliéter no se encontraron diferencias significativas. Para todos los materiales de impresión se encontraron diferencias significativas con y sin aplicación de adhesivo y el modelo maestro, sin embargo con aplicación de adhesivo se encontró resultados más exactos. Con la silicona de adición se obtuvieron modelos más exactos tanto con como sin aplicación de adhesivo.
The purpose of this study was to compare the dimensional accuracy of three impression materials with and without application of adhesives. The materials used were: condensation silicone Oranwash L, Zetaplus (Zhermack®), addition silicone Elite H-D (Zhermack®) and Polyether ImpregumÕ Soft (3M ESPE). A master model, was made of stainless steel, which simulated one hemi-arch with preparations for fixed prosthesis. For each material, 20 impressions were made ,in which 10 of them had adhesive over the tray impression and to the other 10 had no adhesive applied. Seven measures were taken :M1, M2, M3, M4, M5, M6 y M7, of the stone cast and were evaluated by means of a machine of measurement that coordinates, Beyond 700 /900 Mitutoyo Corporation®, to compared them with the measures of a master model. Student's t - test was used to compare the measures with and without application of adhesive, and between the stone casts and the master model. Analysis of Variation (Tukey) was used to compare between impression materials. Significant differences were found between the ones that had been added and those without the application of adhesive, for condensation silicone in the M7 measurement and for additional silicone in the M6 measurement; whereas polyether had no significant difference. Significant differences were found between all the materials with and without adhesive application and the master model, however the ones with the adhesive application result more accurate. The addition silicone was the material that showed more accurate results with and without adhesive application.