Effects of different surface treatments and adhesive self-etch functional monomers on the repair of bulk fill composites: A randomised controlled study

Igor R Blum; Renáta Martos; Melinda Szalóki; Christopher D Lynch; Csaba Hegedűs

doi:10.1016/j.jdent.2021.103637

Effects of different surface treatments and adhesive self-etch functional monomers on the repair of bulk fill composites: A randomised controlled study

J Dent. 2021 May:108:103637. doi: 10.1016/j.jdent.2021.103637. Epub 2021 Mar 22.

Authors

Igor R Blum¹, Renáta Martos², Melinda Szalóki³, Christopher D Lynch⁴, Csaba Hegedűs⁵

Affiliations

¹ Faculty of Dentistry, Oral & Craniofacial Sciences, King's College London, London, United Kingdom. Electronic address: igor.blum@kcl.ac.uk.
² Department of Restorative Dentistry, Faculty of Dentistry, University of Debrecen, Nagyerdei krt. 98., H4032, Debrecen, Hungary. Electronic address: martos.renata@dental.unideb.hu.
³ Department of Biomaterials and Prosthetic Dentistry, Faculty of Dentistry, University of Debrecen, Nagyerdei krt. 98., H4032, Debrecen, Hungary. Electronic address: szaloki.melinda@dental.unideb.hu.
⁴ Department of Restorative Dentistry, University Dental School and Hospital, University College Cork, Wilton, Cork Ireland, Ireland. Electronic address: chris.lynch@ucc.ie.
⁵ Department of Biomaterials and Prosthetic Dentistry, Faculty of Dentistry, University of Debrecen, Nagyerdei krt. 98., H4032, Debrecen, Hungary. Electronic address: hegedus.csaba.prof@dental.unideb.hu.

PMID: 33766513
DOI: 10.1016/j.jdent.2021.103637

Abstract

Objective: To evaluate the effect of different adhesive protocols on the microtensile bond strength (μTBS) and integrity of the repaired bulk fill composite interface.

Methods: Two hundred and seventy composite blocks made of bulk fill composites of different viscosity were randomly assigned to 18 surface conditioning groups (n = 15/group). The universal adhesive systems used were Heliobond™, Tokuyama bond force II™ and Scotchbond Universal™. A nanohybrid resin composite was applied as the repair material. Negative and positive control groups were included. Stick shape specimens of each group were subjected to μTBS testing. Representative samples from all test groups were subjected to microscopic, proﬁlometric and SEM examination to determine their mode of failure. The data were analysed statistically using two-way ANOVA test, Tukey's test and the independent t-test (α = 0.05).

Results: The mean μTBS of all test groups ranged between 28.5 and 46.8 MPa and varied with the type of adhesive system employed. Signiﬁcantly highest μTBS values were obtained when Tokuyama bond force II™ and Scotchbond Universal™ adhesives were used (p < 0.01) which were comparable to the coherent strength of the bulk fill resin composite in the positive control groups (p > 0.05). The viscosity of the bulk fill composite did not significantly influence repair bond strength. The microscopy and SEM examination of the failed interfaces revealed a mixture of adhesive and cohesive failures.

Conclusions: Under the tested conditions, signiﬁcantly greater μTBS of repaired bulk fill composite was achieved when the substrate surface was treated with adhesive systems containing a functional monomer.

Clinical significance: Eﬀ ;ecting a repair of a bulk fill resin composite restoration with the application of a functional monomer containing adhesive system, such as Tokuyama Bond Force II™ or Scotchbond Universal™, would seem to enhance the interfacial bond strength and integrity of the repaired resin composite interface.

Keywords: Adhesive systems; Bulk fill composite; Repair.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Composite Resins
Dental Bonding*
Dental Cements
Materials Testing
Resin Cements
Surface Properties
Tensile Strength

Substances

Composite Resins
Dental Cements
Resin Cements