Table 5.

RET study characteristics

Author year	Study design	Size	Tooth type	Age (y) mean	Aetiology	TG	Irrigant	DRE	DRE, weeks	Scaff-old	Barrier	Outcome	Follow-up, months	Drop- out
Ulusoy (2019)	RCT	88	100%A	8–11	100% T	I = 66; C = 22	1.25% NaOCl; 2% CHX; 17% EDTA	TAP (20 mg Clinda, 20 mg Cipro, 20 mg Metro)	4	PRF; PRP; PP; BC	WMTA	100% AP-healing; 82% PP C-apexification 76% BC C-apexification 71% PRF C-apexification 67% PRP C-apexification 4% O-apexification; 22% No IRL/IRT; 86% Positive PST	28.25 ± 1.2	n = 12
Chan (2016)	LCS	28	82% A 10% P 8% M	9	79% T 36% DA 7% DC	I = 28; C = 0	5.25% NaOCl	TAP (100 mg Cefa, 500 mg Cipro, 500 mg Metro)	2–6	BC	CB +  WMTA	100% AP-healing; 96% survival, 93% clinical success; 92% IRL; 82% IRT; 31% C-apexification; 54% P-apexification; 15% N-apexification; 100% Negative PST	30 ± 12,7	n = 2

RCT randomised clinical trial, LCS longitudinal cohort study, N study size, A anterior tooth, P premolar, M molar, T trauma, DA dental anomalies, DC dental caries, TG treatment groups, PRP platelet rich plasma, PRF platelet rich fibrin, PP platelet pellet, DRE root canal dressing, BC induced blood clot, CH calcium hydroxide, TAP triple antibiotic paste, CHX chlorhexidine gluconate, I intervention group, C control group, WMTA white MTA Pro Root, CB collagen barrier: Clinda-clindamycin: Cipro-ciprofloxacin, Metro metronidazole, Cefa cefaclor, AP healing-radiographic resolution of apical pathology, Positive PST positive response to pulp sensitivity tests, Negative PST negative response to pulp sensitivity tests, IRL increase in root length, IRT increase in root thickness, C-apexification complete apical closure, P-apexification partial apical closure, N-apexification no apical closure, O-apexification ongoing apical closure