Study Year of
publication 		Study
design 		Patient number Study
group 		Analysed
effect 		Intervention Scar width
(control) 		Scar width
(experimental) 		P-values VAS/VSS
results 		P-value Key
outcomes
Refahee et al. [20] 2020 Randomized clinical trial 24 Experimental: 12; control: 12 Impact of platelet concentrates on scar formation Platelet-rich plasma injection post-Millard technique Ultrasound:
4.96 (0.93) mm.
Photographic point 1:
1.49 (0.44) mm;
photographic point 1:
2.28 (0.98) mm 		Ultrasound:
3.8 (0.89) mm.
Photographic point 1:
0.83 (0.23) mm;
photographic point 2:
1.02 (0.1) mm 		P ≤ 0.0003 N/A N/A Platelet-rich plasma significantly reduced scar width
Sonane et al. [21] 2022 Randomized clinical trial 22 Experimental: 12; control: 10 Effect of botulinum toxin Botulinum toxin A injection post-crossed triangular flaps technique Point 1:
0.514 (0.34);
point 2:
0.511 (0.26) mm 		Point 1:
0.395 (0.23) mm;
point 2:
0.424 (0.42) mm 		P < 0.05 VAS:
experimental 6.77 (0.65)
vs.
control 5.46 (0.35).
VSS:
no significant difference 		P = 0.01
and
P > 0.05 		Improved scar appearance at 6 months; significant VAS improvement
Chang et al. [22] 2014 Randomized clinical trial 59 Experimental: 30; control: 29 Effect of botulinum toxin Botulinum toxin A injection post-modified rotation flap technique Point 1:
0.45 (0.11) mm;
point 2:
0.47 (0.13) mm 		Point 1:
0.33 (0.11) mm;
point 2:
0.33 (0.13) mm 		P < 0.05 VAS:
experimental 8.43
vs.
control 7.19.
VSS:
no significant difference 		P < 0.001
and
P > 0.05 		Smaller scar widths; improved VAS score
Lu et al. [23] 2022 Randomized clinical trial 55 Experimental: 24; control: 31 Effect of botulinum toxin Botulinum toxin A injection at two
vs.
three points post-rotation flap technique 		0.96 (0.1) mm
(2 points) 		0.59 (0.5) mm
(3 points) 		P > 0.05 VSS:
no significant difference 		P > 0.05 No statistically significant difference between groups
Luthra et al. [24] 2016 Randomized clinical trial 20 Experimental: 10; control: 10 Effect of different wound closure methods Non-absorbable sutures (6-0 nylon)
vs.
absorbable sutures (Vicryl Rapide®) 		N/A N/A N/A VSS/VAS:
significantly better with non-absorbable sutures 		P < 0.05 Non-absorbable sutures resulted in smoother scars with better pigmentation and elasticity
Nosheen Jan et al. [25] 2020 Randomized clinical trial 300 Experimental: 150;
control: 150 		Effect of different wound closure methods Cyanoacrylate
(tissue adhesive)
vs.
non-absorbable sutures 		N/A N/A N/A VAS/HWES:
no significant difference, but adhesives reduced hypertrophic scars and complications 		P > 0.05
and
P < 0.001 		Adhesives led to fewer infections and revisions
James et al. [26] 2021 Randomized clinical trial 38 Experimental: 20; control: 18 Effect of different wound closure methods Synthetic tissue
adhesives
vs.
5-0 Prolene® suture 		N/A N/A N/A VAS:
no significant difference.
HWES:
no significant difference 		P = 0.052 and
P = 0.152 		Comparable scar outcomes; adhesives had similar complications
Chang et al. [27] 2018 Retrospective clinical study 62 Experimental: 33; control: 29 Effect of silicone-based wound coverings Silicone dressing vs. silicone ointment Point 1:
0.45 (0.11) mm;
point 2:
0.47 (0.13) mm 		Point 1:
0.4 (0.15) mm;
point 2:
0.49 (0.37) mm 		P > 0.05 VAS:
no significant difference.
VSS:
no significant difference 		P > 0.05 No significant differences in scar formation between groups
Halli et al. [28] 2012 Retrospective clinical study 60 Experimental: 30; control: 30 Effect of different wound closure methods Tissue adhesive
vs.
6-0 Prolene® sutures 		N/A N/A N/A VAS:
no significant difference.
Closure time:
adhesive 4.34 min
vs
sutures 7.45 min 		P > 0.05
and
P < 0.01 		Tissue adhesives reduced closure time

VSS = Vancouver Scar Scale; HWES = Hollander Wound Evaluation Score; VAS = Visual Analog Scale.