Table 2.

Characteristic of studies.

Title	Author (Year)	Study design	Sample size	Type of intervention and comparison	Follow-up (timepoint)	Complete Root Coverage	Mean Root Coverage	Vertical Recession (mm)	Keratinized Tissue Width (mm)	Clinical Attachment Level(mm)	Probing Depth(mm)	Recession Width(mm)
Treatment of Localized Gingival Recessions using Gingival Unit Grafts: A Randomized Controlled Clinical Trial	Kuru et al., 2013	RCT	17 patients with Class I to II recession defects on mandibular anterior teeth	Gingival Unit Transfer and Free Gingival Graft	Baseline, 3months, 8months	50% sites achieved complete root coverage in GUG and 0% in FGG	91.62% GUG 68.97% FGG	3.50 ± 0.53 (Baseline GUG) 0.94 ± 0.72 (GUG 3 months) 0.31 ± 0.44 (GUG 8 months) 3.55 ± 0.88 (Baseline FGG) 1.33 ± 0.36(FGG 3 months) 1.16 ± 0.79 (FGG 8 months)	1.43 ± 0.62(BaselineGUG) 7.12 ± 0.58 (8 months GUG) 1.72 ± 0.83Baseline FGG) 5.94 ± 1.18 (8months FGG)	4.75 ± 0.70BaselineGUG) 1.12 ± 0.44 (8 months GUG) 4.88 ± 0.78(Baseline FGG) 2.27 ± 0.79 (8months FGG)	1.25 ± 0.46(BaselineGUG) 0.81 ± 0.25 (8 months GUG) 1.33 ± 0.50(Baseline FGG) 1.16 ± 0.79 (8months FGG)
Gingival Unit Graft Versus Free Gingival Graft for Treatment of Gingival Recession: A Randomized Controlled Clinical Trial	Jenabian et al., 2016	RCT	9patients, 18 bilateral localized recessions of Miller class I and II	Gingival Unit Transfer and Free Gingival Graft	Baseline, 1month, 3months, 6 months	11% sites achieved complete root coverage in GUG and 0% in FGG	60.52% GUG 45.52% FGG	4.11 ± 1.63(BaselineGUG) 2.72 ± 1.09 (1 months GUG) 2.38 ± 1.29 (3 months GUG) 1.83 ± 1.47 (6 months GUG) 3.72 ± 1.46(Baseline FGG) 2.83 ± 0.93 (1 month FGG) 2.61 ± 1.08 (3monthFGG) 2.00 ± 1.11 (6 months FGG)	2.44 ± 1.52(BaselineGUG) 5.94 ± 1.07 (1 months GUG) 5.33 ± 1.03 (3 months GUG) 5.05 ± 1.01 (6 months GUG) 2.16 ± 1.47(Baseline FGG) 5.38 ± 1.43 (1 month FGG) 4.83 ± 1.52 (3monthFGG) 4.38 ± 1.36 (6 months FGG)	5.33 ± 1.85(BaselineGUG) 3.72 ± 0.83 (1 months GUG) 3.50 ± 1.14 (3 months GUG) 2.66 ± 1.56 (6 months GUG) 5.05 ± 1.66(Baseline FGG) 3.72 ± 1.00 (1 month FGG) 3.72 ± 1.12 (3monthFGG) 3.00 ± 1.17 (6 months FGG)	1.22 ± 083(BaselineGUG) 1.00 ± 0.50 (1 months GUG) 1.11 ± 0.33 (3 months GUG) 0.83 ± 0.25 (6 months GUG) 1.44 ± 0.28(Baseline FGG) 0.77 ± 0.08 (1 month FGG) 1.11 ± 0.11 (3monthFGG) 1.00 ± 0.08 (6 months FGG)	3.00 ± 1.19(BaselineGUG) 2.50 ± 0.82 (1 months GUG) 2.11 ± 0.82 (3 months GUG) 1.94 ± 0.72 (6 months GUG) 3.16 ± 1.54(Baseline FGG) 2.50 ± 1.17 (1 month FGG) 2.66 ± 1.19 (3monthFGG) 2.44 ± 1.21 (6 months FGG)
Comparison of free gingival graft and gingival unit graft for treatment of gingival recession: A Randomized Controlled Clinical Trial	Sriwil et al., 2020	RCT	30 bilateral localized recessions of Miller class I and II	Gingival Unit Transfer and Free Gingival Graft	Baseline, 1month, 3months, 6 months	13% sites achieved complete root coverage in GUG and 0% in FGG	92.74 ± 8.81% in GUG 66.94 ± 11.43% in the FGG	3.42 ± 0.67(BaselineGUG) 1.54 ± 0.56 (1 months GUG) 0.27 ± 0.20 (6 monthsGUG) 3.50 ± 0.68(Baseline FGG) 2.19 ± 0.43 (1months FGG) 1.15 ± 0.43 (6 months FGG)	2.44 ± 0.78(BaselineGUG) 8.23 ± 0.86 (1 months GUG) 6.27 ± 0.67 (6 monthsGUG) 2.54 ± 0.75(Baseline FGG) 7.38 ± 0.62 (1months FGG) 5.62 ± 0.74 (6 months FGG)	4.85 ± 0.99(BaselineGUG) 2.38 ± 0.55 (1 months GUG) 0.85 ± 0.83 (6 monthsGUG) 4.77 ± 1.01(Baseline FGG) 3.25 ± 0.67 (1months FGG) 2.15 ± 0.24 (6 months FGG)	2.04 ± 0.83(BaselineGUG) 1.04 ± 0.43 (1 months GUG) 1.04 ± 0.43 (6 monthsGUG) 2.23 ± 0.73(Baseline FGG) 1.81 ± 0.63 (1months FGG) 1 ± 0.35 (6 months FGG)