Physico-mechanical properties of all commercially available bulk fill composites
J. LEPRINCE1,2, G. LELOUP1,2
1School of Dentistry and Stomatology, Universite catholique de Louvain, Brussels, BELGIUM,
2 Institute of Condensed Matter and Nanosciences – Bio- and Soft- Matter, Universite catholique de Louvain, Louvain-la-Neuve, Belgium
Objective: Bulk-fill composites are an emerging class of resin-based composites, which is claimed to enable the restoration build up in thick layers, up to 4mm. The objective of this work was to compare the mechanical properties of all currently available bulk fill composites to those of two conventional composite materials chosen as references, one highly filled and one flowable nano-hybrid composite: Grandio (G-REF1,VOCO) and GrandioFlow (GF-REF2,VOCO).
Methods: TetricEvoCeramBulkFill (TECBF,Ivoclar-Vivadent), VenusBulkFill (VBF,Heraeus-Kuzer), SDR (Dentsply), X-traFil (XF,VOCO), X-traBase (XB,VOCO), SonicFill (SF,Kerr), FiltekBulkFill (FBF,3M-Espe), Xenius (X,GC), and compared to the two reference materials. They were light-cured during 40s in a 2x2x25mm Teflon mould. Elastic modulus (E) and flexural strength (FS) were evaluated by three points bending (n=5), surface hardness using Vickers microindentation before (VNHdry) and after 24 hours ethanol storage (VHNeth) (n=5), and filler weight content by thermogravimetric analysis (Fwt) (n=3). VHNratio (VHNeth/VHVdry) was considered as an evaluation of crosslinking density. Data were analyzed by one-way ANOVA and Tukey's test (p=0.05).
Results:
Materials
| Fwt(%)
| VHNdry
| VHNeth
| VHNratio(%)
| E(Gpa)
| FS(Mpa)
|
G-REF1
| 85.3(0.1)a
| 120.8(5.0)a
| 99.0(5.9)a
| 82.2(8.2)a
| 15.3(0.8)a
| 125.0(5.9)abc
|
GF-REF2
| 79.1(0.2)c
| 66.8(3.9)b
| 55.7(3.6)c
| 83.5(6.4)a
| 8.0(0.3)cd
| 115.0(17.6)abcd
|
XF
| 85.2(0.5)a
| 70.9(7.2)b
| 60.1(1.9)bc
| 85.5(9.8)a
| 9.4(0.4)b
| 130.7(7.9)ab
|
SF
| 83.1(0.1)b
| 71.8(1.9)b
| 65.3(2.4)b
| 91.0(1.8)a
| 8.6(0.6)bc
| 140.3(14.2)a
|
X
| 74.4(0.1)d
| 52.3(4.3)c
| 35.8(0.7)d
| 68.7(5.4)b
| 8.3(0.2)cd
| 101.4(12.1)cdef
|
XB
| 74.2(0.3)d
| 47.0(1.4)c
| 28.2(2.7)e
| 60.1(6.4)bc
| 7.4(0.6)d
| 110.5(16.5)bcde
|
TECBF
| 73.1(0.9)d
| 47.7(3.7)c
| 31.9(3.9)de
| 67.3(9.3)b
| 6.1(0.5)e
| 94.5(7.0)def
|
SDR
| 69.0(1.2)e
| 31.3(0.6)d
| 6.0(0.1)g
| 19.2(0.3)e
| 4.7(0.4)f
| 100.2(3.9)cdef
|
VBF
| 61.5(0.1)f
| 21.7(0.9)e
| 9.6(0.4)fg
| 44.3(2.5)d
| 3.3(0.0)g
| 76.0(12.8)f
|
FBF
| 60.7(0.2)f
| 28.7(0.7)de
| 14.3(0.5)f
| 49.8(2.4)cd
| 3.7(0.4)fg
| 88.4(14.2)ef
|
| Mean(±standard deviation)Similar letters within columns=no significant difference
| |||||
Conclusion:
The mechanical properties of the bulk-fill composites are mostly lower than G-REF1. They are at best comparable to those of GF-REF2, but in general inferior. This can partly be explained by a lower filler content, but not only. VHNratio indeed reveals large differences in crosslinking density between the investigated materials.