Table 1.

Characteristic of the studies included (humans) in the systematic review.

Author (Year)	Country	Type of Study	Age	Type of Teeth	Experimental Materials	Comparing Materials	Follow-up	Outcomes
Cobanoglu et al. 2021 [19]	Turkey	Controlled clinical trial	23–35	Third molars	Clearfil Protect Bond	Clearfil SE Bond and CH	90 days	CH group showed better hard-tissue formation than the experimental group.
Sharma et al. 2021 [20]	India	Controlled clinical trial	15–30	Premolars	Endosequence Root Repair Material and Endocem MTA	ProRoot MTA	30 days	The mean thickness of dentin-bridge formation in ProRoot MTA was greater than the other two experimental groups.
Holiel et al. 2021 [21]	Egypt	Controlled clinical trial	15–25	Premolars	Treated dentin matrix hydrogel	Biodentine and MTA	2 weeks and 2 months	Complete dentin-bridge formation was observed with numerous dentinal tubule lines showing a positive trend to dentin regeneration.
Holiel et al. 2021 [22]	Egypt	Randomized clinical trial	18–40	Permanent posterior teeth	Treated dentin matrix hydrogel	Biodentine and MTA	3, 6, 12, 18, and 24 months	Dentin-bridge formation was significantly superior of a higher thickness than Biodentine and MTA.
Hoseinifar et al. 2020 [23]	Iran	Randomized clinical trial	14–25	Premolars	Calcium-enriched mixture	MTA and Biodentine	6 weeks	No significant differences were observed between the groups in terms of the dentine bridge formation.
Suzuki et al. 2019 [24]	Japan	Controlled clinical trial	18–33	Third molars	CO2 laser irradiation	Dycal	6 and 12 months	Self-etching adhesive system following CO2 laser irradiation without carbonization of the exposed pulp demonstrated dentin-bridge formation that was comparable to Dycal.
Mahendran et al. 2019 [25]	India	Controlled clinical trial	18–24	Premolars	Simvastatin + α-TCP and atorvastatin + α-TCP	MTA	7, 30, and 90 days	No significant difference was observed in terms of hard-tissue formation between the groups.
Jalan et al. 2017 [26]	India	Randomized clinical trial	15–25	Premolars	Biodentine	CH	45 days	Dentin-bridge formation was significantly thicker and more continuous with Biodentine in comparison to Dycal.
Nowicka et al. 2016 [11]	Poland	Controlled clinical trial	19–30	Third molars	Single-bond universal	CH	6 weeks	Single-bond universal showed less dentin-bridge formation than CH.
Nowicka et al. 2015 [27]	Poland	Controlled clinical trial	19–32	Third molars	MTA, Biodentine, single-bond universal	CH	6 weeks	MTA and Biodentine groups showed significantly higher dentin-bridge formation than CH and single-bond universal groups.
Swarup et al. 2014 [28]	India	Controlled clinical trial	11–15	Premolars	Nano hydroxyapatite	MTA, CH	15 and 30 days	Continuous dentin-bridge formation was observed in the nano hydroxyapatite and MTA groups. Only MTA group showed regular pattern of dentinal tubules.
Parolia et al. 2010 [29]	India	Controlled clinical trial	15–25	Premolars	Propolis, MTA	Dycal	15 and 45 days	Propolis and MTA showed more dentin-bridge formation than Dycal group.
Accorinte et al. 2008 [30]	Brazil	Controlled clinical trial	15–30	Premolars	Clearfil LB 2V and Clearfil SE Bond	CH	30 and 90 days	Few specimens showed dentin-bridge formation in the experimental group, whereas CH showed dentin-bridge formation almost all the specimens.
Accorinte et al. 2008 [31]	Brazil	Controlled clinical trial	15–30	Premolars	MTA	CH	30 and 60 days	CH showed faster hard-tissue formation compared to MTA and a similar response with the hard-tissue bridge in almost all cases was observed.
Accorinte et al. 2008 [32]	Brazil	Controlled clinical trial	15–30	Premolars	MTA	CH	30 and 60 days	Dentin-bridge formation was lower in the CH group compared to MTA group.
Sawicki et al. 2008 [33]	Poland	Controlled clinical trial	10–18	Immature premolars	WMTA	CH	47–609 days	Complete, thicker, and more solid dentin bridge was observed in the WMTA group when compared with CH.
Lu et al. 2008 [34]	China	Controlled clinical trial	20–25	Third molars	Clearfil SE Bond	CH	7, 30, and 90 days	The dentin-bridge formation in the experimental group was significantly lower compared to CH group.
Min et al. 2008 [35]	Korea	Controlled clinical trial	21–50	Third molars	MTA	CH	2 months	The thickness of the dentin-bridge formation in the MTA group was statistically greater than CH group.
Nair et al. 2006 [36]	UK	Randomized controlled trial	18–30	Third molars	MTA	Dycal	1 week, 1 month, and 3 months	Complete hard-tissue formation was observed in the MTA group, whereas less consistent formation of hard-tissue barrier with numerous tunnel defect was observed in the Dycal group.
Silva et al. 2006 [37]	Brazil	Controlled clinical trial	12–20	First premolars	Single-bond adhesive system	CH	30 days	No dentin formation at the exposure area in the single-bong adhesive system group, whereas dentin-bridge formation was observed in the CH group.
Iwamoto et al. 2006 [38]	USA	Controlled clinical trial	18–60	Third molars	WMTA	CH	136 ± 24 days	WMTA showed a dentin-bridge formation similar to CH’s.

CH, calcium hydroxide; MTA, mineral trioxide aggregate; WMTA, white mineral trioxide aggregate; α-TCP, α-tricalcium phosphate.