Microtensile Bond Strength of Nonmetallic Dowels Bonded to Radicular Dentin with Self-Etch Adhesives

Purpose: The bonding potential of nonmetallic dowels to root dentin, particularly with new self-etch adhesives, has not been fully investigated. The aim of this study was to determine microtensile bond strength (μTBS) of nonmetallic dowels, including a novel glass fiber dowel, when bonded to radicular dentin with self-etch adhesives.
Materials and Methods: Crowns of extracted anterior teeth were severed, and endodontic treatment was performed. Teeth were divided into six groups according to dowel/adhesive. Teeth received dowels as follows: group I: Light Post + Clearfil-SE Bond/Panavia-F (SE/PF), group II: Light Post + Xeno III/Panavia-F (XN/PF), group III: ParaPost Fiber White + SE/PF, group IV: ParaPost Fiber White + XN/PF, group V: everStick Post + SE/PF, and group VI: everStick Post + XN/PF. Teeth were sectioned to produce 1 mm specimens from both cervical and middle thirds with the dowel at the center. Specimens were tested in a special machine, and μTBS values were determined.
Results: Mean μTBS values and SDs in MPa for the cervical region were as follows: group I: 10.36 (1.88), group II: 8.51 (1.41), group III: 11.61 (1.06), group IV: 9.37 (1.61), group V: 14.22 (1.16), and group VI: 12.97 (1.69). Group V had the highest mean value—significantly higher than the means of groups I, II, III, and IV ( p < 0.0001 to p < 0.02). For the middle region: group I, 9.72 (1.61); group II, 7.62 (1.42); group III, 10.28 (0.75); group IV, 8.48 (1.51); group V, 13.23 (1.06); group VI, 11.07 (1.49). Group V also had highest mean value—significantly higher than the means of groups I, II, III, and IV ( p < 0.0001 to p < 0.004).
Conclusions: everStick glass fiber dowel, bonded with either adhesive, showed the highest μTBS. Microtensile bond strengths were not significantly different with cervical root dentin than with middle root dentin.