Influence of adhesive-composite application modalities on their bonding to tooth structure and resistance of the performed restorations to failure

• Published in: Journal of dental sciences 2018-12, Vol.13 (4), p.378-385
• Main Authors: Abdelaziz, Khalid M., Saleh, Ahmed A.
• Format: Article
• Language: English
• Subjects: Bond strength; Curing; Failure resistance; Original; Resin adhesive; Resin composite
• ISSN: 1991-7902; 2213-8862
• DOI: 10.1016/j.jds.2018.08.003

The longevity of bonded composite restorations could be affected by the utilized adhesive-composite application techniques. This in vitro study aimed to evaluate the influence of adhesive-composite application modalities on their bonding values to tooth structure and on the failure resistance of the performed restorations on loading. Resin composite studs, 2 mm in diameter and 4 mm high, were bonded in 2 groups to flattened enamel and dentin surfaces of 80 extracted premolars using pre-cured (PC) and co-cured (CC) self-etch resin adhesive. Studs in each group were built-up in 4 subgroups using either multiple increments of nano-filled composite (IF, control) or single increment of preheated nano-filled (PH), bulk-fill (BF) and sonic-activated bulk-fill composites (SF). Another 80 premolars with standard class II cavities were also restored using the same adhesive-composite application modalities. All specimens were then stressed on a universal testing machine to assess the composite-tooth shear bond strength and the resistance of the performed restorations to failure. The modes of specimens’ failure were also assessed following each test. The PC adhesive provided higher bond strength to dentin (p 0.05%). Both PH and BF composites showed lower bond strength to dentin in presence of PC adhesive (p  0.05). PH and SF restorations presented the highest resistance to failure (p