Structural/Chemical Characterization and Bond Strength of a New Self-Adhesive Bulk-fill Restorative

J Adhes Dent. 2020;22(1):85-97. doi: 10.3290/j.jad.a44000.

Abstract

Purpose: The material structure and chemical elemental composition of a new self-adhesive composite hybrid were investigated. The bonding performance when applied on flat (FLAT) vs high C-factor class-I cavity-bottom (CAVITY) dentin and in light-cure (LC) vs self-cure (SC) mode was determined.

Materials and methods: The self-adhesive bulk-fill composite Surefil One (Su-O; Dentsply Sirona) was compared with the resin-modified glass-ionomer Fuji II LC Improved (Fuji2LC; GC) and the ion-releasing alkasite material Cention N (CentionN; Ivoclar Vivadent). The material structure was examined with SEM and TEM, while the chemical elemental composition was analyzed using EDS. The immediate and aged microtensile bond strength (μTBS) of Su-O_LC/SC was compared to that of Fuji2LC applied without any pre-treatment, and to that of CentionN applied following bonding with Adhese Universal (AU) (Ivoclar Vivadent) in self-etch mode (AU/CentionN). All restorative materials were bonded onto FLAT and CAVITY dentin. Statistical analysis was performed with the Kruskal-Wallis nonparametric test.

Results: EDS analysis revealed that Su-O was richer in C and P than the reference restorative materials. Applied to FLAT dentin, the significantly highest immediate and aged μTBS were recorded for AU/CentionN, which were not significantly different only from Su-O_LC. Applied to CAVITY dentin, the significantly highest immediate μTBS was recorded for AU/CentionN, which did not differ significantly only from Su-O_SC. Su-O_LC bonded to CAVITY dentin suffered from a high incidence of pre-test failures.

Conclusion: While Su-O_LC bonded effectively and durably to FLAT dentin, Su-O_SC bonded more favorably than Su-O_LC in class-I cavities, which was probably related to shrinkage stress variously challenging the respective bond.

Keywords: EDS; TEM; adhesion; aging; composite; curing.

MeSH terms

  • Composite Resins
  • Dental Bonding*
  • Dental Cements
  • Dentin
  • Dentin-Bonding Agents*
  • Materials Testing
  • Resin Cements
  • Tensile Strength

Substances

  • Composite Resins
  • Dental Cements
  • Dentin-Bonding Agents
  • Resin Cements