Fracture behavior of Bi-structure fiber-reinforced composite restorations

Lippo Lassila; Eija Säilynoja; Roosa Prinssi; Pekka K Vallittu; Sufyan Garoushi

doi:10.1016/j.jmbbm.2019.103444

Fracture behavior of Bi-structure fiber-reinforced composite restorations

J Mech Behav Biomed Mater. 2020 Jan:101:103444. doi: 10.1016/j.jmbbm.2019.103444. Epub 2019 Sep 20.

Authors

Lippo Lassila¹, Eija Säilynoja², Roosa Prinssi², Pekka K Vallittu³, Sufyan Garoushi⁴

Affiliations

¹ Department of Biomaterials Science and Turku Clinical Biomaterial Center -TCBC, Institute of Dentistry, University of Turku, Turku, Finland.
² Research Development and Production Department, Stick Tech Ltd - Member of GC Group, Turku, Finland.
³ Department of Biomaterials Science and Turku Clinical Biomaterial Center -TCBC, Institute of Dentistry, University of Turku, Turku, Finland; City of Turku Welfare Division, Oral Health Care, Turku, Finland.
⁴ Department of Biomaterials Science and Turku Clinical Biomaterial Center -TCBC, Institute of Dentistry, University of Turku, Turku, Finland. Electronic address: sufgar@utu.fi.

PMID: 31561057
DOI: 10.1016/j.jmbbm.2019.103444

Abstract

Objective: The aim of this study was to evaluate the fracture-behavior of direct composite restorations made with two different composite-core materials. In addition, fracture toughness (FT), flexural strength (FS) and flexural modulus (FM) of tested composites were evaluated.

Methods: Twenty groups of posterior crown restorations were fabricated (n = 6/group). The groups were made of a 4-5 mm layer of composite-core materials (everX Flow and SDR Flow⁺) and covered by a 2 mm layer of conventional composite (G-aenial Anterior & Posterior, G-aenial Universal Injectable, Essentia, CeramX, Filtek Z500). Control groups were only made of conventional composites or composite-core materials. Crowns were statically loaded until fracture. Failure-modes were then visually examined. FT, FS and FM were determined for each tested composite (n = 6).

Results: ANOVA revealed that crown restorations made only from everX Flow composite had significantly higher load-bearing capacities (3866 ± 263 N) (p < 0.05) among all the groups tested. No statistically significant differences were found in the load-bearing capacities between crowns made with different composite-core materials (p > 0.05). everX Flow exhibited the highest FT (2.8 MPa m^1/2) and Z500 presented the highest FS values (197 MPa) (p < 0.05) among tested composites. With regard to the failure-mode analysis, crowns that had a fiber-reinforced core material of everX Flow revealed delaminating of surface conventional composite from the substructure layer. While in crowns that had a core material of SDR Flow⁺ or having only conventional composites with no fiber reinforcement, showed a crushing fracture pattern.

Conclusion: Restorations combining a fiber-reinforced composite core and a surface layer of conventional composite, displayed promising performance related to fracture-behavior.

Keywords: Bi-structure restoration; Fiber composite; Fracture behavior; Posterior crown.

Publication types

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

MeSH terms

Crowns*
Dental Materials
Mechanical Phenomena*
Prosthesis Failure

Substances

Dental Materials