Objective: To study whether the bond strength between enamel and composite resin could be enhanced by intraoral sand abrasive.
Methods: Ten human maxillary first incisior teeth were divided into 2 groups The experimental group was sandblasted with 30 microm Al2O3 (CoJet-Sand, pressure 300 kPa) from a distance of 5 mm for 5 seconds, and the control group were not sandblasted. The Herculite composite resin composite cylinders were bonded with Coltene system. Bonded specimens were stored in 37 degrees C distilled water for 24 h, then were subjected to shear force in a testing machine. Stress at failure was calculated in Mpa, and mode of failure was recorded. The Student t test was applied to the data.
Results: The shear bond strength of experimental groups was (33.0+/-1.8) MPa, and that of control groups was (26.7+/-5.2) MPa,there was significant difference between these two groups. All the adhesive failures happened at the enamel composite resin interface, except that cohesive failure happened in one sandblasted specimen.
Conclusion: Intraoral sandblasting could significantly enhance the shear bond strength between enamel and composite resin.