Contemporary flowable bulk-fill resin-based composites: a systematic review

Figures & data

Table 1. Search strategy.

Pubmed	(((bulk-fill) OR (bulkfill)) AND ((flowable) OR (flow))) AND (“flexural strength”) (((bulk-fill) OR (bulkfill)) AND ((flowable) OR (flow))) AND (“polymerization shrinkage”) (((bulk-fill) OR (bulkfill)) AND ((flowable) OR (flow))) AND (((“polymerization stress”) OR (“polymerization shrinkage stress”)) OR (“shrinkage stress”)) (((bulk-fill) OR (bulkfill)) AND ((flowable) OR (flow))) AND (“degree of conversion”)
Scopus	TITLE-ABS-KEY ((((bulk-fill) OR (bulkfill)) AND ((flowable) OR (flow))) AND (“flexural strength”)) TITLE-ABS-KEY ((((bulk-fill) OR (bulkfill)) AND ((flowable) OR (flow))) AND (“polymerization shrinkage”)) TITLE-ABS-KEY ((((bulk-fill) OR (bulkfill)) AND ((flowable) OR (flow))) AND (((“polymerization stress”) OR (“polymerization shrinkage stress”)) OR (“shrinkage stress”))) TITLE-ABS-KEY ((((bulk-fill) OR (bulkfill)) AND ((flowable) OR (flow))) AND (“degree of conversion”))
Web of Science	TS=((((bulk-fill) OR (bulkfill)) AND ((flowable) OR (flow))) AND (“flexural strength”)) TS=((((bulk-fill) OR (bulkfill)) AND ((flowable) OR (flow))) AND (“polymerization shrinkage”)) TS=((((bulk-fill) OR (bulkfill)) AND ((flowable) OR (flow))) AND (((“polymerization stress”) OR (“polymerization shrinkage stress”)) OR (“shrinkage stress”))) TS=((((bulk-fill) OR (bulkfill)) AND ((flowable) OR (flow))) AND (((“polymerization stress”) OR (“polymerization shrinkage stress”)) OR (“shrinkage stress”)))

Table 2. Inclusion criteria.

Degree of conversion	Studies with spectroscopy-based evaluation methods and 4 mm depth samples.
Polymerization shrinkage stress	Studies that measure stress (MPa) and not force, through a universal testing machine or other device designed for this purpose.
Polymerization shrinkage	Studies measuring volumetric shrinkage (%), using microtomography as a method of evaluation.
Flexural strength	Studies measuring flexural strength (MPa) using the 3-point bending test.

Figure 1. Flow diagram of the article identification and inclusion process.

Table 3. Overview of resin composites and their composition according to manufacturers.

Material	Code	Resin Matrix	Filler	Load (% weight/% volume)
Filtek Bulk Fill Flow (3 M)	FBF	Bis-GMA, Bis-EMA, UDMA, procrylat resins	Combination of zirconia/silica and ytterbium trifluoride filler	64.5%/42.5%
SureFil SDR Flow (Dentsply)	SDR	Modified UDMA, EBPADMA, TEGDMA	Barium and Strontium alumino-fluoro-silicate glasses	68%/45%
Tetric EvoFlow Bulk Fill (Ivoclar-Vivadent)	TEBF	Bis-GMA, Bis-EMA,TCDDA	Ytterbium, Trifluoride, Barium aluminium silicate glass and copolymer	68.2%/46.4%
Beautifil Bulk Flowable (Shofu)	BBF	BisGMA, UDMA, Bis-MPEPP, TEGDMA	S-PRG filler based on fluoroboro aluminosilicate glass	72.5%/N.A.
Venus Bulk Fill (Kulzer)	VBF	UDMA,EBPDMA	Ba-Al-F-Si glass, SiO2, ytterbium trifluoride	65%/38%
X-tra base (Voco)	XTB	Aliphatic dimethacrylate, Bis-EMA	N.A.	75%/ N.A.
SDR Plus (Dentsply)	SDR+	Modified UDMA, TEGDMA	Barium and Strontium alumino-fluoro-silicate glasses, ytterbium fluoride;	70.5%/47.4%
Tetric Power Flow (Ivoclar-Vivadent)	TPF	Bis-GMA, TCDDA	barium glass, ytterbium trifluoride and copolymers	68.2%/46.4%
Bulk base /Bulk base Medium Flow/ Bulk base High Flow (Sun Medical)	BB/BBM/ BBH	N.A.	N.A.	N.A.
Filtek Fill and Core (3M)	FCF	N.A.	N.A.	N.A.
Estelite bulk fill flow (Tokuyama)	EBF	Bis-GMA, Bis-MPEPP, TEGMA	Supra Nano spherical SiO2-ZrO2	70%/56%
G-aenial Bulk Injectable (GC)	GBF	Bis EMA, UDMA	barium glass, silica	N.A.

Bis-GMA: bisphenol A diglycidyl ether dimethacrylate; BisEMA: ethoxylated bisphenol A glycol dimethacrylate; UDMA: urethane dimethacrylate; EBPADMA: Ethoxylated bisphenol A dimethacrylate; TEGDMA: triethyleneglycol dimethacrylate; TCDDA: tricyclodecane dimethanol diacrylate; Bis-MPEPP: Bisphenol A polyethoxy methacrylate; N.A.: not available.

Table 4. Degree of conversion main informed results.

Study	Materials	Degree of Conversion (%)
Al-Ahdal et al. Dent Mater 2015 https://doi.org/10.1016/j.dental.2015.07.004	FBF BBF VBF XTB	55.8–62.3^a 56.3–65.7^a 66.6–74.8^a 49.4–57.7^a
Albuquerque et al. Eur J Gen Dent 2021 https://doi.org/10.4103/ejgd.ejgd_14_19	SDR	73.20/74.64^c
Braga et al. Oper Dent 2019 https://doi.org/10.2341/17-351-L	SDR	64.6/75.6^b
Czasch et al. Clin Oral Investig 2013 https://doi.org/10.1007/s00784-012-0702-8	SDR VBF	58.3–61.2^c 62.9–67.92^c
Fronza et al. Dent Mater 2015 https://doi.org/10.1016/j.dental.2015.10.001	FBF SDR	75.3 81.2
Gonçalves et al. Braz. Oral Res 2018 https://doi.org/10.1590/1807-3107bor-2018.vol32.0017	FBF VBF	41.0 86.0
Harp et al. J Esthet Restor Dent. 2022 https://doi.org/10.1111/jerd.12901	SDR+ TEBF	60.2 47.5
Hayashi et al. Dent Mater 2020 https://doi.org/10.1016/j.dental.2020.10.012	TEBF TPF	58.7 60.1
Lempel et al. Int J Mol Sci 2016 https://doi.org/10.3390/ijms17050732	FBF SDR XTB	19.41/32.71^c 50.05^c 28.77/34.01^c
Lempel et al. Dent Mater 2019 https://doi.org/10.1016/j.dental.2018.11.017	FBF SDR	36.7–49.2^c 42.8–63.0^c
Lempel et al. Dent Mater 2021 https://doi.org/10.1016/j.dental.2021.02.013	SDR+	65
Majidinia et al. Dental Hypotheses 2020 https://doi.org/10.4103/denthyp.denthyp_41_19	FBF	63.06/66.28^c
Marigo et al. Eur Rev Med Pharmacol Sci 2015	SDR	64.67
Marovic et al. Acta Odontol Scand 2015 https://doi.org/10.3109/00016357.2014.992810	SDR VBF XTB	70.0 78.8 67.5
Monterubbianesi et al. Front Physiol 2016 https://doi.org/10.3389/fphys.2016.00652	SDR	75.67–93.17^a,b
Papadogiannis et al. Dent Mater 2015 http://doi.org/10.1016/j.dental.2015.09.022	SDR VBF XTB	63.20 58.49 45.83
Par et al. Oper Dent 2015 https://doi.org/10.2341/14-091-L	FBF SDR VBF XTB	63.4 74.7 83.3 66.3
Siagian et al. J Contemp Dent Pract 2020 https://doi.org/10.5005/jp-journals-10024-2848	SDR	41.76
Sousa-Lima et al. Oper Dent 2017 https://doi.org/10.2341/16-299-L	TEBF	85.7
Theobaldo et al. Clin Cosmet Investig Dent 2017 https://doi.org/10.2147/CCIDE.S130803	SDR	79.97–84.16^b,d
Yu et al. Oper Dent 2017 https://doi.org/10.2341/16-027-L	SDR BBF	69.38 53.17
Zorzin et al. Dent Mater 2015 http://doi.org/10.1016/j.dental.2014.12.010	FBF SDR VBF XTB	66.4/69.26 52.04/72.18 80.07/73.93 62.53/61.53

^aDifferent times post-cure. ^bDifferent light curing units. ^cDifferent curing times or modes ^dDifferent preheating temperatures.

FBF: Filtek Bulk Fill Flow; SDR: SureFil SDR Flow; TEBF: Tetric EvoFlow Bulk Fill; BBF: Beautifil Bulk Flowable; VBF: Venus Bulk Fill; XTB: X-tra Base; SDR+: SDR Plus; TPF: Tetric Power Flow; EXF: EverX Flow; BB: Bulk Base; BBM: Bulk Base Medium Flow; BBH: Bulk Base High Flow; FCF: Filtek Fill and Core.

Table 5. Polymerization shrinkage main informed results.

Study	Materials	Polymerization shrinkage (%)
Algamaiah et al. J Esthet Restor Dent 2017 http://doi.org/10.1111/jerd.12275	FBF SDR	3.47/4.07^a 3.65/3.78^a
Haugen et al. Int J Mol Sci 2020 http://doi.org/10.3390/ijms21145136	SDR FBF	3.36 3.39
Hirata et al. Biomed Mater Res B Appl Biomater 2015 http://doi.org/10.1002/jbm.b.33258	SDR	1.5/2.0^a
Kamalak & Kamalak. Biomed Res 2018 https://doi.org/10.4066/biomedicalresearch.29-18-314	SDR FBF XTB	1.54 2.04 1.26
Oglakci et al. J Adhes Sci Technol 2020 https://doi.org/10.1080/01694243.2020.1782038	SDR+ EBF	4.4/10.41^b 4.07/10.45^b
Prager et al. Dent Mater J 2018 https://doi.org/10.4012/dmj.2017-136	SDR VBF	6.55 4.07
Rizzante, Duque et al. Dent Mater J 2019 https://doi.org/10.4012/dmj.2018-063	FBF SDR XTB	3.34 3.36 3.11
Sampaio et al. Oper Dent 2017 https://doi.org/10.2341/15-296-L	FBF SDR	5.49 3.31
Sampaio et al. Dent Mater 2019 https://doi.org/10.1016/j.dental.2019.07.025	FBF TEBF	3.50 2.75

^aSamples with/ without adhesive. ^bSamples with/without thermo-mechanical ageing.

FBF: Filtek Bulk Fill Flow; SDR: SureFil SDR Flow; TEBF: Tetric EvoFlow Bulk Fill; BBF: Beautifil Bulk Flowable; VBF: Venus Bulk Fill; XTB: X-tra Base; SDR+: SDR Plus; TPF: Tetric Power Flow; EXF: EverX Flow; BB: Bulk Base; BBM: Bulk Base Medium Flow; BBH: Bulk Base High Flow; FCF: Filtek Fill and Core.

Table 6. Polymerization shrinkage stress informed results.

Study	Materials	Shrinkage stress (MPa)
Attik et al. Dent Mater 2022 https://doi.org/10.1016/j.dental.2021.12.029	SDR+	3.44
De Freitas Chaves et al. J Conserv Dent 2020 http://doi.org/10.4103/jcd.Jcd_58_19	FBF SDR XTB	19.45 24.24 18.68
Fronza et al. J Adhes Dent 2018 http://doi.org/10.2341/16-024-l	FBF	3.87
Fronza et al. Dent Mater 2015 http://doi.org/10.1016/j.dental.2015.10.001	FBF SDR	3.5 3.3
Han et al. Oper Dent 2017 http://doi.org/10.2341/16-023-L	SDR VBF	3.02 3.46
Han et al. J Dent 2019 https://doi.org/10.1016/j.jdent.2018.10.013	SDR	2.76
Kim et al. J Dent 2015 http://doi.org/10.1016/j.jdent.2015.02.002	FBF SDR	2.24 1.68
Kim et al. Oper Dent 2016 http://doi.org/10.2341/15-260-l	FBF SDR	2.28 1.70
Nakano et al. Oper Dent 2020 http://doi.org/10.2341/19-166-l	FBF TEBF	2.3 2.8
Rizzante et al. J Appl Oral Sci 2019 http://doi.org/10.1590/1678-7757-2018-0132	FBF SDR XTB	0.28/0.43^a 0.19/0.24^a 0.31/0.51^a
Sousa-Lima et al. Oper Dent 2017 https://doi.org/10.2341/16-299-L	TEBF	0.77
Velo et al. Braz Dent J 2019 http://doi.org/10.1590/0103-6440201902571	FBF SDR	0.13 0.23
Zorzin et al. Dent Mater 2015 http://doi.org/10.1016/j.dental.2014.12.010	FBF SDR VBF XTB	1.55/1.47^b 1.33/ 1.29^b 1.65/ 1.74^b 1.45/ 1.68^b

^aDifferent sample volumes (12mm³/24mm³), ^bDifferent curing times (manufacturer’s instructions/30s).

FBF: Filtek Bulk Fill Flow; SDR: SureFil SDR Flow; TEBF: Tetric EvoFlow Bulk Fill; BBF: Beautifil Bulk Flowable; VBF: Venus Bulk Fill; XTB: X-tra Base; SDR+: SDR Plus; TPF: Tetric Power Flow; EXF: EverX Flow; BB: Bulk Base; BBM: Bulk Base Medium Flow; BBH: Bulk Base High Flow; FCF: Filtek Fill and Core.

Table 7. Flexural strength main informed results.

Study	Materials	Flexural strength (MPa)
Alrahlah. J Contemp Dent Pract 2018 http://doi.org/10.1016/j.dental.2015.07.004	SDR	138.5/130.02^a
Attik et al. Dent Mater 2022 http://doi.org/10.1016/j.dental.2021.12.029	SDR+	115.7
Czasch et al. Clin Oral Investig 2013 http://doi.org/10.1007/s00784-012-0702-8	SDR VBF	131.8 122.7
de Freitas Chaves et al. J Conserv Dent 2020 http://doi.org/10.4103/jcd.Jcd_58_19	FBF SDR XTB	135.98 115.75 89.82
Gilli et al. Oper Dent 2022 http://doi.org/10.2341/21-084-L	FBF SDR VBF XTB	121.7 147.8 115.114 132.2
Hirokane et al. Oper Dent 2021 https://doi.org/10.2341/20-253-L	FBF BBF BBM SDR+ GBF	117.4/103.0^a 122.5/105.0^a 102.0/93.1^a 122.0/111.0^a 143.9/129.4^a
Ilie et al. Oper Dent 2013 https://doi.org/10.2341/12-395-L	FBF SDR VBF XTB	122.4 131.8 122.7 139.4
Jung & Park. Oper Dent 2017 https://doi.org/10.2341/16-254-L	SDR VBF	101.26 97.36
Lassila et al. Odontology 2019 https://doi.org/10.1007/s10266-018-0405-y	FBF SDR TEBF	122 120 97
Leprince et al. J Dent 2014 http://doi.org/10.1016/j.jdent.2014.05.009	FBF SDR VBF XTB	88.4 100.2 76.0 110.5
Nitta et al. Dent Mater J 2017 http://doi.org/10.4012/dmj.2016-394	FBF ^aBBM ^aBBH	132.8 96.2 89
Öznurhan et al. J Clin Pediatr Dent 2015 http://doi.org/10.17796/1053-4628-39.3.241	SDR XTB	45.0 40.96
Shimatani et al. Oper Dent 2020 https://doi.org/10.2341/18-160-L	SDR XTB BBF BB FCF	105.7 110.4 102.1 68.9 116.1
Sousa-Lima et al. Oper Dent 2017 https://doi.org/10.2341/16-299-L	TEBF	76.6
Tsujimoto et al. Polymers 2021 https://doi.org/10.3390/polym13162613	FBF	50.3/144.9^b
Oh et al. Biomater Res 2022 https://doi.org/10.1186/s40824-022-00267-5	SDR	127.69 − 135.83^c

^aSamples with/without thermo-mechanical ageing. ^bDifferent times post-cure. ^cDifferent irradiation distance.

FBF: Filtek Bulk Fill Flow; SDR: SureFil SDR Flow; TEBF: Tetric EvoFlow Bulk Fill; BBF: Beautifil Bulk Flowable; VBF: Venus Bulk Fill; XTB: X-tra Base; SDR+: SDR Plus; TPF: Tetric Power Flow; EXF: EverX Flow; BB: Bulk Base; BBM: Bulk Base Medium Flow; BBH: Bulk Base High Flow; FCF: Filtek Fill and Core; GBF: G-aenial Bulk Injectable.

Table 8. Quality assessment of risk of bias of in vitro studies (QUIN tool).

Study	Risk of Bias	Study grading
Al-Ahdal K et al. Dent Mater 2015 https://doi.org/10.1016/j.dental.2015.07.004	58.33%	Medium risk
Albuquerque et al. Eur J Gen Dent 2021 https://doi.org/10.4103/ejgd.ejgd_14_19	58.33%	Medium risk
Alrahlah et al. J Contemp Dent Pract 2018 https://doi.org/10.5005/jp-journals-10024-2205	58.33%	Medium risk
Algamaiah et al. J Esthet Restor Dent 2016 https://doi.org/10.1111/jerd.12275	66.67%	Medium risk
Attik et al. Dent Mater 2022 https://doi.org/10.1016/j.dental.2021.12.029	58.33%	Medium risk
Braga et al. Oper Dent 2019 https://doi.org/10.2341/17-351-L	62.5%	Medium risk
Czasch et al. Clin Oral Investig 2013 https://doi.org/10.1007/s00784-012-0702-8	54.17%	Medium risk
De Freitas et al. J Conserv Dent 2020 https://doi.org/10.4103/JCD.JCD_58_19	62.5%	Medium risk
Fronza et al. Dent Mater 2015 https://doi.org/10.1016/j.dental.2015.10.001	66.67%	Medium risk
Fronza et al. J Adhes Dent 2018 https://doi.org/10.3290/j.jad.a40987	54.17%	Medium risk
Gilli et al. Oper Dent 2022 http://doi.org/10.2341/21-084-L	58.33%	Medium risk
Gonçalvez et al. Braz Oral Res 2018 https://doi.org/10.1590/1807-3107bor-2018.vol32.0017	58.33%	Medium risk
Han et al. Oper Dent 2017 https://doi.org/10.2341/16-023-L	70.83%	Low risk
Han et al. J Dent 2019 https://doi.org/10.1016/j.jdent.2018.10.013	70.83%	Low risk
Harp et al. J Esthet Restor Dent 2022 https://doi.org/10.1111/jerd.12901	62.50%	Medium risk
Haugen et al. Int J Mol Sci 2020 https://doi.org/10.3390/ijms21145136	62.5%	Medium risk
Hayashi et al. Dent Mater 2020 https://doi.org/10.1016/j.dental.2020.10.012	58.33%	Medium risk
Hirata et al. Biomed Mater Res B Appl Biomater 2014 https://doi.org/10.1002/jbm.b.33258	54.17%	Medium risk
Hirokane et al. Oper Dent 2021 https://doi.org/10.2341/20-253-L	66.67%	Medium risk
Ilie et al. Oper Dent 2013 https://doi.org/10.2341/12-395-L	58.33%	Medium risk
Jung & Park Oper Dent 2017 https://doi.org/10.2341/16-254-L	58.33%	Medium risk
Kamalak & Kamalak Biomed Res 2018 10.4066/biomedicalresearch.29-18-314	50%	High risk
Kim et al. J Dent 2015 https://doi.org/10.1016/j.jdent.2015.02.002	58.33%	Medium risk
Kim et al. Oper Dent 2016 https://doi.org/10.2341/15-260-L	58.33%	Medium risk
Lassila et al. Odontology 2019 https://doi.org/10.1007/s10266-018-0405-y	58.33%	Medium risk
Lampel et al. Dent Mater 2021 https://doi.org/10.1016/j.dental.2021.02.013	58.33%	Medium risk
Lempel et al. Int J Mol Sci 2016 https://doi.org/10.3390/ijms17050732	62.5%	Medium risk
Lempel et al. Dent Mater 2019 https://doi.org/10.1016/j.dental.2018.11.017	62.5%	Medium risk
Leprince et al. J Dent 2014 https://doi.org/10.1016/j.jdent.2014.05.009	54.17%	Medium risk
Majidinia et al. Dental Hypotheses 2020 https://doi.org/10.4103/denthyp.denthyp_41_19	58.33%	Medium risk
Marigo et al. Eur Rev Med Pharmacol Sci 2015	58.33%	Medium risk
Marovic et al. Acta Odontol Scand 2014 https://doi.org/10.3109/00016357.2014.992810	62.5%	Medium risk
Monterubbianesi et al. Front Physiol 2016 https://doi.org/10.3389/fphys.2016.00652	58.33%	Medium risk
Nakano et al. Oper Dent 2020 https://doi.org/10.2341/19-166-L	54.17%	Medium risk
Nitta et al. Dent Mater J 2017 https://doi.org/10.4012/dmj.2016-394	58.33%	Medium risk
Oglakci et al. J Adhes Sci Technol 2020 https://doi.org/10.1080/01694243.2020.1782038	62.50%	Medium risk
Oh et al. Biomater Res 2022 https://doi.org/10.1186/s40824-022-00267-5	58.33%	Medium risk
Öznurhan et al. J Clin Pediatr Dent 2015 https://doi.org/10.17796/1053-4628-39.3.241	54.17%	Medium risk
Papadogiannis et al. Dent Mater 2015 https://doi.org/10.1016/j.dental.2015.09.022	54.17%	Medium risk
Par et al. Oper Dent 2015 https://doi.org/10.2341/14-091-L	58.33%	Medium risk
Prager et al. Dent Mater J 2018 https://doi.org/10.4012/dmj.2017-136	58.33%	Medium risk
Rizzante et al. J Appl Oral Sci 2019 https://doi.org/10.1590/1678-7757-2018-0132	54.17%	Medium risk
Rizzante et al. Dent Mater J 2019 https://doi.org/10.4012/dmj.2018-063	54.17%	Medium risk
Sampaio et al. Oper Dent 2016 https://doi.org/10.2341/15-296-L	70.83%	Low risk
Sampaio et al. Dent Mater 2019 https://doi.org/10.1016/j.dental.2019.07.025	70.83%	Low risk
Shimatani et al. Oper Dent 2020 https://doi.org/10.2341/18-160-L	62.5%	Medium risk
Siagian et al. J Contemp Dent Pract 2020 https://doi.org/10.5005/jp-journals-10024-2848	54.17%	Medium risk
Sousa-Lima et al. Oper Dent 2017 https://doi.org/10.2341/16-299-L	58.33%	Medium risk
Theobaldo et al. Clin Cosmet Investig Dent 2017 https://doi.org/10.2147/CCIDE.S130803	62.5%	Medium risk
Tsujimoto et al. Polymers 2021 https://doi.org/10.3390/polym13162613	54.17%	Medium risk
Velo et al. Braz Dent J 2019 https://doi.org/10.1590/0103-6440201902571	62.5%	Medium risk
Yu et al. Oper Dent 2017 https://doi.org/10.2341/16-027-L	54.17%	Medium risk
Zorzin et al. Dent Mater 2015 https://doi.org/10.1016/j.dental.2014.12.010	58.33%	Medium risk

RoB <50% high risk; 50%<RoB < 70% medium risk; RoB > 70% low risk.