Der Einfluss von zwei Desensitizern auf die Scherfestigkeiten von Keramiken auf Dentin

Objective: The aim of the present study was to evaluate the influence of desensitizer application (Hyposen, Lege Artis and Gluma Desensitizer, Heraeus Kulzer) on shear bond strength of ceramics to dentin. Material and methods: 72 freshly extracted third molars were included. Standardized cervical dentin specimens were prepared allowing the simulation of dentin perfusion. The specimens were divided at random into six experimental groups: Group VC: no desensitizer/ Variolink II; Group VH: Hyposen/ Variolink II; Group VG: Gluma/ Variolink II; Group BC: no desensitizer/ Bifix SE; Group BH: Hyposen/ Bifix SE; Group BG: Gluma/ Bifix SE. The desensitizers and adhesive cements were applied as recommended by the manufacturer. Shear bond strength of the above mentioned adhesive cements with or without desensitizer application to ceramic (IPS Empress, Ivoclar Vivadent) was measured using a special device in a universal testing machine. Results: The following shear bond strengths were obtained (mean values and standard deviations in MPa): Group VC: 5.56 ± 0.61, Group VH: 5.28 ± 0.96, Group VG: 3.04 ± 0.18, Group BC: 3.60 ± 1.38, Group BH: 3.60 ± 1.36, Group BG: 2.06 ± 0.16. Statistical analysis showed a significant influence of the used desensitizer and adhesive cement on shear bond strength (ANOVA). Treatment with Gluma (VG, BG) resulted in significantly lower bond strength values (p0.001; Tukey's Test). Pairwise comparison between the adhesive cements showed significantly higher values for Variolink II (p0.001; Tukey's Test). Within the limitations of an in vitro investigation it can be concluded that the application of desensitizers reduce the shear bond strength of all tested adhesive systems. Parole chiave: adhesives, ceramics, desensitizer, resin cements, shear bond strength