Table 2 Brand, type, manufacturer, chemical compositions of the materials used in this study, and application protocol.

FL-Bond II

Two-step self- etching adhesive system with S-PRG

Shofu Inc, Kyoto, Japan

Primer: water, ethanol, carboxylic acid monomer, phosphoric acid monomer, and initiator

Adhesive: S-PRG filler based on fluoro-boro- aluminosilicate glass, UDMA, TEGDMA, 2-HEMA, initiator

1. Acid etchant was applied for 15 s on enamel

2. Rinse for 20 s/air dried surface

3. Apply primer for 20 s (one drop)

4. Solvent evaporation for 20 s

5. Apply bonding agent, do not air dry

6. Light cure for 20s

Beautifil Bulk Restorative

Bulk Fill resin composite with S-PRG

Shofu Inc, Kyoto, Japan

Bis-GMA, UDMA, Bis-MPEPP, TEGDMA, S-PRG filler based on fluoroboroaluminosilicate glass, polymerization initiator,

pigments and others.

Single increment (4 mm) and light-cured for 40 s

Scotchbond Universal

Universal adhesive system

3 M Oral Care, Minesota, USA

Methacryloyloxydecyl dihydrogen phosphate, phosphate monomer, dimethacrylate resins, hydroxyethyl methacrylate, methacrylate-modified polyalkenoic acid copolymer, filler, ethanol, water, silane, camphorquinone.

1. Acid etchant was applied for 15s on enamel

2. Rinse for 20 s/air dried surface

3. Apply adhesive for 20 s (two layers)

4. Solvent evaporation for 20 s

5. Light cure for 20 s

Filtek One Bulk Fill

Bulk Fill resin composite

3 M Oral Care, Minesota, USA

Organic Matrix: AUDMA, UDMA, and 1,12-dodecane-DMA Fillers: non- agglomerated/non- aggregated 20 nm silica filler, a non- agglomerated/non- aggregated 4 to 11 nm zirconia filler, aggregated zirconia/ silica cluster filler (comprised of 20 nm silica to 4 to 11 nm zirconia particles), and ytterbium trifluoride filler of 100 nm particles; 76.5 wt 58.4 vol% Other components: camphorquinone.

Single increment (4 mm) and light-cured for 40 s

Colgate Total 12

(clean mint)

Toothpaste

Colgate-Palmolive, São Paulo, Brazil

Glycerin, agua, hydrated silica, sodium lauryl sulfate, arginine, aroma, zinc oxide, cellulose gum, benzyl alcohol, poloxamer 407, zinc citrate, tetrasodium pyrophosphate, xanthan gum, cocamidopropyl betaine, sodium fluoride (1450 ppm), sodium saccharin, phosphoric acid, sucrolose.

Ratio of 1:3 (toothpaste: deionized water) for 2 min.

Only CTF, BBF and FBF groups.

Abbreviations: 2-HEMA, 2-hydroxyethylmethacrylate;10-MDP, 10-methacryloyloxydecyl dihydrogen phosphate; bis-GMA, bisphenol A-glycidyl methacrylate; bis-MPEPP, bisphenol A polyethoxy methacrylate; S-PRG, surface-reaction PRG; TEGDMA, triethylene glycol dimethacrylate; UDMA, urethane dimethacrylate, AUDMA: aromatic urethane dimethacrylate; Bis-MPEPP- bisphenol A polyethoxy methacrylate.