Evaluación de la interfase adhesiva obtenida en restauraciones de resina compuesta realizadas con un sistema adhesivo universal utilizado con y sin grabado ácido previo

Objective

The purpose of this research was to study the tooth-restoration adhesive interface, using a universal adhesive system (Single Bond Universal, 3M/ESPE, Germany), with the techniques of etching and self-etching using scanning electron microscopy.

Material and methods

Class V cavities were prepared in buccal and palatine/lingual surface, in human teeth. Etching with 37%H₃PO₄ was performed in the buccal cavity, with no etching being performed in the palatine or lingual cavity. The samples were placed in an oven at 37 °C and 100% humidity for 48 hours, simulating the oral environment. The samples were cut perpendicularly through the restoration and prepared to be observed by scanning electron microscopy, in order to evaluate the adhesive interface in relation to the presence of breaches and the formation of resin tags.

Results

Images were observed with a gradual increase to 2000×. Microstructural differences were observed in the penetration of the adhesive but with no formation of breaches in the adhesive interface.

Conclusions

An unbreached interface is obtained when using both techniques. In enamel, less penetration was present in the crystal structure of the adhesive with the self-etching technique. While in dentin, with the same technique, a less thick hybrid layer and shorter resin tags were observed.