Bulk Fill Composites Have Similar Performance to Conventional Dental Composites

Abstract

The aim of the study was to perform comprehensive characterization of two commonly used bulk fill composite materials (SDR Flow (SDR) and Filtek™ Bulk Fill Flowable Restorative (FBF) and one conventional composite material (Tetric EvoCeram; TEC). Eleven parameters were examined: flexural strength (FS), flexural modulus (FM), degree of conversion, depth of cure, polymerisation shrinkage (PS), filler particle morphology, filler mass fraction, Vickers hardness, surface roughness following simulated toothbrush abrasion, monomer elution, and cytotoxic reaction of human gingival fibroblasts, osteoblasts, and cancer cells. The degree of conversion and depth of cure were the highest for SDR, followed by FBF and TEC, but there was no difference in PS between them. FS was higher for bulk fill materials, while their FM and hardness were lower than those of TEC. Surface roughness decreased in the order TEC→SDR→FBF. Bisphenol A-glycidyl methacrylate (BisGMA) and urethane dimethacrylate were found in TEC and FBF eluates, while SDR released BisGMA and triethylene glycol dimethacrylate. Conditioned media accumulated for 24h from FBF and TEC were cytotoxic to primary human osteoblasts. Compared to the conventional composite, the tested bulk fill materials performed equally or better in most of the tests, except for their hardness, elastic modulus, and biocompatibility with osteoblasts.

Rapid 3 s Curing: What Happens in Deep Layers of New Bulk-Fill Composites?

“…Additionally, the optical path length of through the material is one of the crucial factors that reduce the number of photons available to initiate the polymerization in deeper areas [ 21 ]. It is a well-known fact that bulk-fill composites have higher light transmission, which allows their placement in 4 mm thick layers [ 22 ], but that does not imply that the surface and the 4 mm depth have identical properties [ 23 , 24 , 25 ].…”

Influence of Curing Time on the Microbiological Behavior of Bulk-Fill Nanohybrid Resin Composites

“…Bulk-fill resin-based composites (RBCs) have been introduced in the last decade to simplify restoration procedures, allowing for a higher depth of cure of a single increment (they can be placed in ≥4 mm thick bulks instead of the conventional incremental placement of 2 mm-thick layers) [1][2][3][4][5][6]. This goal was reached by modifying the composition of an RBC, for instance, by lowering the filler content by volume in low-viscosity bulk fills and increasing the dimensions of filler particles (>20 microns); thus, decreasing their specific surface areas.…”

“…This goal was reached by modifying the composition of an RBC, for instance, by lowering the filler content by volume in low-viscosity bulk fills and increasing the dimensions of filler particles (>20 microns); thus, decreasing their specific surface areas. It was shown that these modifications improved light transmission, while lower filler content decreases hardness with no change in the suggested curing time [5,6].…”

“…Furthermore, the polymerization shrinkage and the consequent stress on the interfaces were reduced using high-molecular-weight monomers to improve marginal adaptation [7,8]. Bulk-fill RBCs are, in fact, a family of materials that differ from conventional RBCs in many ways, ranging from strategies adopted to enhance its translucency, such as a reduction in the content of the pigment and the use of larger filler particles, to significant changes in the chemical composition such as the use of high-molecular-weight monomers and stress-relieving monomers [5,[9][10][11].…”

Nano-CT as tool for characterization of dental resin composites

“…Elliot et alpioneered the use of micro-computed tomography (micro-CT) in dental research in the early 1980s 15 , 16 , it becoming a popular tool in dental research due to its non-destructive method of viewing samples 17 . Micro-CT has been widely used to investigate composite materials 18 – 20 , particularly in the analysis of polymerisation shrinkage 19 – 23 . The 3D imaging has advanced significantly over the years, however, there are still obstacle when analysing porous biomaterials 24 .…”