Objectives:To evaluate the microtensile bond strength (MTBS) of Futurabond to enamel and dentin surfaces following different treatments. Method: Flat enamel surfaces from bovine incisors and flat medium dentin surfaces from extracted human third molars were used. Futurabond self-etching dental adhesive system was applied: 1) Following manufacturer´s directions. 2) After pre-etching with 35% H3PO4 (for 15 sec). 3) After etching with 35% H3PO4 and 5% NaOCl application (for 2 min). 4) Application time was doubled to 60 sec.5) Duplicating the number of adhesive coats. Resin composite build-ups (6 mm in height) were constructed incrementally (1.5 mm) with Arabesk resin composite. After storage for 24 h in water at 37°C, the bonded teeth were sectioned into serial slabs, and further into beams with cross-sectional areas of 1 mm2. Each beam was tested in tension in an Instron machine at 0.5 mm/min. Results were analysed by one-way ANOVA and post-hoc multiple comparisons with SNK (p<0.05).
Results: Mean (SD) µTBS values (MPa), (n=10) are shown in the table. Same letter indicates no influence of the mode of application.
Futurabond Group 1 Group 2 Group 3 Group 4 Group 5
Enamel 21.3 (10.2) A 27.5 (10.2) A ----------- 19.1 (7.1) A 23.6 (8.9) A
Dentin 15.3 (10.7) a 19.5 (11.0) ab 17.2 (8.74) a 30.2 (9.3) c 22.4 (10.0)ab
Conclusions: On enamel, no influence of the application parameters was detected. On dentin, lower strengths were obtained when Futurabond was applied following manufacturer´s directions. A duplicated application time increased its bond strength to dentin. (CICYT/FEDER. Grant#MAT2001-2843-CO2. RED CYTED VIII.J)