Depth of Cure, Hardness, Roughness and Filler Dimension of Bulk-Fill Flowable, Conventional Flowable and High-Strength Universal Injectable Composites: An In Vitro Study

Abstract

(1) Objective: To evaluate and compare the depth of cure (DOC) of two bulk-fill flowable composites (Filtek Bulk Fill Flowable Restorative and Tetric EvoFlow Bulk Fill), two conventional flowable composites (Filtek Supreme XTE Flowable Restorative and G-ænial Flo X) and one high-strength universal injectable composite (G-ænial Universal Injectable). (2) Methods: specimens were placed in a stainless-steel mold with an orifice of 4 mm in diameter and 10 mm in depth and light-cured for 20 s using a light emitting diode (LED) light-curing unit (LCU) with an irradiance of 1000 mW/cm2; depth of cure was assessed using the ISO 4049 scrape technique, and the absolute length of the specimen of cured composite was measured in millimeters with a digital caliper. The same procedure was repeated with 14 samples for each material under investigation, for a total number of 70 test bodies. Material roughness and hardness results were also investigated using, respectively, a 3D laser confocal microscope (LEXT OLS 4100; Olympus) at ×5 magnification and a Vickers diamond indenter (Vickers microhardness tester, Shimadzu®, Kyoto, Japan) under 10-N load and a 30 s dwell time. SEM images at 3000 and 9000 magnification were collected in order to study the materials’ filler content. Statistical analysis were performed by a commercial statistical software package (SPSS) and data were analyzed using multiple comparison Dunnett’s test. (3) Results: The average DOC of both bulk-fill composites was more than 4 mm, as a range of 3.91 and 4.53 mm with an average value of 4.24 and 4.12 mm, while that of the conventional flowable composites was much lower, as a range of 2.47 and 2.90 mm with an average value of 2.58 and 2.84 mm; DOC of the high-strength injectable composite was greater than the one of traditional composites, but not to the level of bulk-fill materials, as a range of 2.82 and 3.01 mm with an average value of 3.02 mm. Statistical analysis revealed significant differences (p-values < 0.05) in the depth of cure between bulk fill flowable composites and other composites, while there was no difference (p-values > 0.05) between the materials of the same type. (4) Conclusions: Bulk-fill flowable composites showed significantly higher depth of cure values than both traditional flowable composites and high-strength injectable composites.

Physico-Mechanical Properties of a Newly Developed Base Material Containing Mineral Trioxide Aggregate

“…All BBH specimens cured to a depth of 8 mm (depth of cure >4 mm). The depth of cure of the bulk-fill resin-based composite base materials is reported to be considerably larger than that of conventional resin-based composites [36][37][38]. Therefore, the very large depth of cure of BBH obtained in this study is consistent with previous reports [39,40].…”

Evaluating flexure properties, hardness, roughness and microleakage of high-strength injectable dental composite: an in vitro study

“…All flowable tested materials were marketed as a highstrength injectable restorative composite with Genial Universal FLO having a 69% by-weight filler loading of ultra-fine Strontium particles and Gaenial universal injectable as well having a 69% by-weight filler loading of ultra-fine barium particles [27]. Despite the similar filler loading, the two materials are showing different mechanical and physical performances in the current study.…”

“…On the other hand, Beautifil Injectable was filled with 64% by weight and Beautifil flow plus filled with 60% by weight filler loading, both fillers are based on aluminofluoroborosilicate glass and Al 2 O 3 . The difference in the filler type and weight percent used in tested materials may explain the difference between the behavior of these materials, as each filler material has different mechanical and physical properties and may influence material behavior differently [27]. This is in addition to the Surface hardness is a crucial characteristic that indicates a material's resistance to plastic deformation and abrasion [24,27].…”

“…The difference in the filler type and weight percent used in tested materials may explain the difference between the behavior of these materials, as each filler material has different mechanical and physical properties and may influence material behavior differently [27]. This is in addition to the Surface hardness is a crucial characteristic that indicates a material's resistance to plastic deformation and abrasion [24,27]. This property is influenced by various factors, including the type of resin matrix and the degree of cross-linking during the polymerization reaction.…”

Degree of conversion and physicomechanical properties of newly developed flowable composite derived from rice husk using urethane dimethacrylate monomer

“…A reduction in physical and mechanical properties and an increase in cytotoxicity to the dental pulp cell can occur when the material receives inadequate light penetration. 37 It is postulated that the high depth of cure of UDMA-based FC is much related to its high degree of monomer to polymer conversion, as previously discussed. Apart from the molecular structure and flexibility of monomers, Fujita et al 19 reported that the curing depth of resin composite strongly depended on the transmitted amount of visible light.…”