Influência da arginina na permeabilidade dentinária de um sistema adesivo

Abstract

Considering that the dentin permeability has relevant clinical implications and may jeopardize the success of adhesive procedures, it is essential to study substances that reduce this permeability and its deleterious effects. The objective of the study was to measure the occlusive capacity of arginine-based substances, prior to the application of AdperTM Single Bond 2 adhesive system (3M ESPE), through the evaluation of dentin permeability. A total of 55 dentin discs with a thickness of 1.5 mm were randomly distributed in 5 groups (n=11). After conditioning with 37% phosphoric acid for 15 seconds, the maximum permeability (Lp Max) was obtained. Subsequently, the specimens received the application of the substances proposed according to the groups: CTRL - without substance; ARG - Arginine solution 8%; ARGC - Arginine solution 8% and calcium carbonate 0.15%; nARG - Nanosilica suspension incorporated with arginine 8% and nSI - Suspension of nanosilica. The disks treated with the occlusive substances were subjected to permeability assessment (Lp1), then applied the adhesive system and a new permeability reading was performed (Lp2). Occlusive substances reduced permeability, but there was no difference between groups before and after the application of the adhesive system. In the ARG (Wilcoxon test, p = 0.007), ARGC (p = 0.014) and nSI (p = 0.032) groups, the application of the adhesive system helped to further reduce permeability. The nARG group showed a significant reduction in dentin permeability compared to the group without occlusive substance (CTRL) (Dunn's posttest, p <0.05). It was concluded that the occlusive substances were able to reduce the dentin permeability before the adhesive system application. Among the substances used, the previous use of nanosilica incorporated with 8% arginine was more efficient in reducing dentin permeability.