Table 1 Composition of restorative materials used in the study

X-tra base bulk fill flowable, (XB)

U

Bis-EMA, aluminum, and barium silicate

Filler Content (wt%): 75

(average filler size: 1 μm)

VOCO, Cuxhaven, Germany

2,029,511

X-tra fill bulkfill,

(XF)

U

Bis-GMA, TEGDMA, UDMA, barium aluminum silicate, fumed silica, and pigments

Filler Content (wt%): 86

(average filler size: 2–3 μm)

VOCO, Cuxhaven, Germany

2,029,440

Beautifil Bulk Flowable,

(BF)

U

F-Al-Si glass, Bis-GMA, Bis‐MPEPP, TMGDMA

Filler Content (wt%): 73

(average S-PRG filler size: 0.8 μm)

SHOFU, Kyoto, Japan

22,041

Beautifil Bulk Restorative, (BB)

U

Bis-GMA, UDMA, Bis- MPEPP, TEGDMA, S-PRG filler based on F-Al-Si glass, polymerization initiator, pigments, others,

Filler Content (wt%): 87

(average S-PRG filler size: 0.8 μm)

SHOFU, Kyoto, Japan

31,828

Filtek bulkfill flowable,

(FF)

U

Silane treated ceramics, UDMA, BIS-EMA-6, YbF3, BISGMA, TEGDMA, ethyl 4-dimethylaminobenzoate

Filler Content (wt%): 65

(filler size range of 0.01 to 5 μm)

3 M ESPE, USA

NC36728

Filtek bulkfill posterior,

(FB)

A2

DMA, DDMA, AUDMA, Zirconia/silica cluster filler, ytterbium flüoride

Filler Content (wt%): 77

(filler size range of 0.004-0.1 μm)

3 M ESPE, USA

N693117

Clearfil majesty flow,

(CF)

A2

Hydrophobic aromatic, dimethacrylate, TEGDMA, Camphoroquinone, Barium glass filler, silica filler.

Filler Content (wt%): 81

(filler size range 3–20 μm)

Kuraray Co. Ltd., Osaka, Japan

8A0322

Clearfil Majesty Posterior, (CO)

A2

Bis-GMA, hydrophobic aromatic, dimethacrylate, prepolymerized organic, filler, camphoroquinone, Silane barium glass.

Filler Content (wt%): 92

(filler size range 1.5–20 μm)

Kuraray Co. Ltd., Osaka, Japan

370,001

Clearfil S3 Bond

-

MDP, HEMA, Bis-GMA, water, ethanol, photo-initiator, silanated colloidal silica

Kuraray Co. Ltd., Osaka, Japan

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