. 2023 Aug 16;9:39. doi: 10.1038/s41405-023-00161-9

Table 1.

Composite materials used in this study.

Material	Product	Category	Composition	Manufacture	Shade
Resin-based composite	Te-Econom plus	M	Consists of: dimethacrylate and TEGDMA(22 wt.%). The fillers include barium glass, ytterbium tifluoride, silicon dioxide, and mixed oxide (76 wt.% or 60 vol.%). Additives, initiators, stabilizers, and pigments are additional contents (2 wt.%). The particle size of inorganic fillers is 0.04–7 nm. The mean particle size is 850 nm	Ivoclar vivadent clinical AG Schaan/Liechtenstein	A2
Resin-based composite	Tetric N-ceram	N	Consists of dimethacrylates (19–20 wt.%). The fillers contain barium glass, ytterbium trifluoride, mixed oxide and copolymers (80–81 wt.%). Additives, initiators, stabilizers, and pigments are additional content (< 1 wt.%). The total content of inorganic fillers is 55–57 vol.%. The particle size of inorganic fillers is 40–3000 nm.	Ivoclar vivadent clinical AG Schaan/Liechtenstein	A2

Material

Product

Category

Composition

Manufacture

Shade

Resin-based composite

Te-Econom plus

Consists of: dimethacrylate and TEGDMA(22 wt.%). The fillers include barium glass, ytterbium tifluoride, silicon dioxide, and mixed oxide (76 wt.% or 60 vol.%). Additives, initiators, stabilizers, and pigments are additional contents (2 wt.%). The particle size of inorganic fillers is 0.04–7 nm. The mean particle size is 850 nm

Ivoclar vivadent clinical AG

Schaan/Liechtenstein

Resin-based composite

Tetric N-ceram

Consists of dimethacrylates (19–20 wt.%). The fillers contain barium glass, ytterbium trifluoride, mixed oxide and copolymers (80–81 wt.%). Additives, initiators, stabilizers, and pigments are additional content (< 1 wt.%). The total content of inorganic fillers is 55–57 vol.%. The particle size of inorganic fillers is 40–3000 nm.

Ivoclar vivadent clinical AG

Schaan/Liechtenstein

M (microhybrid composite) and N (nanohybrid composite) are the two types of composite material (shade A2) used in this in vitro study, which are widely used by the Yemeni population.