Influencia del método de remoción de caries en la fuerza de adhesión a dentina afectada

La tecnica de adhesion en dentina es una tecnica poco predecible y se agudiza aun mas cuando la dentina ha sido afectada por caries ya que las alteraciones histologicas disminuyen la posibilidad de esta union; no obstante la variacion en la tecnica de remocion del tejido cariado pudiera influir de manera independiente en la union. El objetivo de esta investigacion es determinar la influencia del metodo de remocion del tejido cariado en la resistencia adhesiva en micro traccion (µTBS) de resina compuesta unida a dentina humana afectada por caries. Se utilizaron 15 molares humanos afectados por caries y de manera aleatoria simple se dividieron en tres grupos (G1,G2,G3), luego se realizo un corte con disco de diamante (KG Sorensen® /Brasil) perpendicular al eje mayor del diente exponiendo la mayor cantidad de dentina afectada, el G1 fue sometido a remocion con Aire abrasivo de oxido de aluminio de 50 µm a una presion de 40 PSI (Microjato®, Bio-art /Brasil), al G2 se le elimino la caries con fresa redonda de carburo N° 6 a baja velocidad (KG Sorensen® /Brasil)y al G3 se le elimino con el metodo Quimico/Mecanico (PAPACARIE ® /Brasil y Cucharita para dentina), la eliminacion fue corroborada con fluorescencia laser (DIAGNOdent®, Kavo /Germany), posteriormente se aplico la tecnica de grabado total siguiendo las indicaciones del fabricante para adhesivo Excite ®( Ivoclar Vivadent Inc. /USA), y se restauraron 6 mm oclusales con resina compuesta Brilliant Enamel New Line® (Coltene-Whaledent /Germany.), luego se seccionaron con una sierra de precision ISOMET 1000® (Buehler /USA) y se obtuvieron muestras de 1x1x10 mm , a continuacion las muestras se prepararon para la prueba de micro traccion en la maquina de prueba universales AGS-J (Shimadzu /Japan) a una velocidad de desplazamiento de 0,5mm por min. Los datos fueron recolectados en hoja de calculo Excel y analizados con un ANOVA de 1 Via, en un nivel (µBts), el valor de p quedo preestablecido en p?0,05 The dentin adhesion technique is a quite unpredictable one and it is enhanced when the dentin has been affected because histological alterations reduce the chance for this union; however, the variation in the removal technique of caries-affected tissue could have an independent influence on the union. Aim: to determine the influence of the method of caries-affected tissue removal on the adhesive resistance in micro-tensile (µTBS) of composite bonded to human dentin affected by caries. Methods: 15 human molars affected by caries were randomly assigned into three groups (G1, G2, and G3). Then, one cut with a diamond disc (KG Sorensen® /Brasil) was performed perpendicular to the major axis of the teeth exposing the larger amount on affected dentin. G1 condition was removal with abrasive air of aluminum oxide of 50 µm at a 40 PSI (Microjato®, Bio-art /Brasil) pressure. G2 had caries removal with carbide round drill N° 6 at a low speed (KG Sorensen® /Brasil). Finally, for G3 caries was removed with the Chemical/Mechanical method (PAPACARIE ® /Brasil and spoon excavator). The elimination was corroborated by laser fluorescence (DIAGNODENT®, Kavo /Germany); later, the total etching technique was performed by following the manufacturer instructions for Excite ® (Ivoclar Vivadent Inc. /USA) and 6 oclusal mm were restored with composite Brilliant Enamel New Line® (Coltene-Whaledent /Germany.), then they were cut with a precision saw ISOMET 1000® (Buehler /USA) and 1x1x10 mm samples were obtained. The samples were prepared for the micro traction test in the universal testing machine AGS-J (Shimadzu /Japan) a speed of 0,5mm per minute. Data were recorded in Microsoft Excel and a one way ANOVA was performed for one level (µBts), the p value was established at p?0,05. Results: the mean µBts in MPa for each group and the standard deviation (±SD) was as follows: G1= 21,7 (8,6) G2=19,70 (10,5) G3=22,2 (9,7)