Fractured teeth bonded with dentin adhesives with and without unfilled resin

Fractured incisors were restored by reattaching the fragment to the remaining tooth structure. For this purpose, seven dentin adhesive systems were used with and without an unfilled resin (Heliobond) and the strength of the restored teeth was tested at a cross-head speed of either 1 or 500 mm/min. The hypothesis was that the strength of the reattachment would be higher when an unfilled resin was used. The dentin adhesive systems were Prime & Bond NT (PB), Excite (EX), One-Step (OS), PQ1 (PQ), SingleBond (SB), Optibond Solo Plus (OS), and an experimental adhesive (GL). Statistical analysis revealed that with all adhesives except EX, a significantly greater mean fracture strength was achieved when the adhesives were used with the resin (Heliobond). Furthermore, with all adhesives except PB, there was a significantly lower mean fracture strength when tested at 500 mm/min than at 1 mm/min. All the tested adhesives except EX should be used with an unfilled resin when restoring fractured teeth by reattachment.