. 2020 Nov 27;10(12):1607. doi: 10.3390/biom10121607

Table 1.

Length of epidermal rete-ridges in human skin over age in various anatomical locations.

Age of Donors	Cohort	Anatomic Location	Mean Length (µm)	Technology Used	Reference
3 months	7 female, 8 male	Upper thigh	50 (estimated)	in vivo Confocal Laser Scanning Microscopy	[29]
		Ventral forearm	35 (estimated)
		Buttock	48 (estimated)
18–30 years	6 female, 4 male Fitzpatrick skin phototype I-III	Forearm	37.6 ± 6.9	Immunostaining on paraffin section and imaging measurements	[28]
18–30 years	6 female, 4 male Fitzpatrick skin phototype I-III	Buttock	61.7 ± 13.2	Immunostaining on paraffin section and imaging measurements	[28]
19–24 years	8 female, 7 male Caucasian	Face–Temple	30 ± 8	in vivo Confocal Laser Scanning Microscopy	[30]
19–24 years	8 female, 7 male Caucasian	Forearm	41 ± 8	in vivo Confocal Laser Scanning Microscopy	[30]
19–29 years	5 female, 7 male Caucasian	Volar arm	97.41 ± 25.93	in vivo Harmonic Generation Microscopy	[31]
21–33 years	10 (mix) Caucasian	Abdomen	60 (estimated)	Immunostaining on frozen sections and imaging measurements	[32]
30–59 years	5 female, 8 male Caucasian	Volar arm	69.59 ± 23.96	in vivo Harmonic Generation Microscopy	[31]
40–65 years	41 female French Fitzpatrick skin phototype II–IV	Forearm	27.01 ± 12.73	in vivo Reflectance Confocal Microscopy	[33]
40–65 years	41 female French Fitzpatrick skin phototype II–IV	Face	13.66 ± 12.73
40–65 years	41 female Brazilian Fitzpatrick skin phototype II–IV	Forearm	28.16 ± 8.23
40–65 years	41 female Brazilian Fitzpatrick skin phototype II–IV	Face	9.21 ± 12.41
51–59 years	7 (mix) Caucasian	Abdomen	35 (estimated)	Immunostaining on frozen sections and imaging measurements	[32]
54–57 years	5 female, 10 male Caucasian	Face–Temple	20 ± 6	in vivo Confocal Laser Scanning Microscopy	[30]
54–57 years	5 female, 10 male Caucasian	Forearm	25 ± 8	in vivo Confocal Laser Scanning Microscopy	[30]
>60 years	6 (mix) Caucasian	Abdomen	15 (estimated)	Immunostaining on frozen sections and manual measurements	[32]
60–79 years	2 female, 4 male Caucasian	Volar arm	58.97 ± 16.70	in vivo Harmonic Generation Microscopy	[31]
>65 years	6 female, 4 male Fitzpatrick skin phototype I-III	Forearm	26.2 ± 4.5	Immunostaining on paraffin sections and manual measurements	[28]
>65 years	6 female, 4 male Fitzpatrick skin phototype I-III	Buttock	46.0 ± 15.3	Immunostaining on paraffin sections and manual measurements	[28]
74–81 years	209 participants Fitzpatrick skin phototype I–IV	Face	5.98 ± 7.11	in vivo Reflectance Confocal Microscopy	[34]
		Forearm	10.55 ± 8.01
		Volar arm	12.94 ± 5.42
	105 females Fitzpatrick skin phototype I–IV	Face	6.41 ± 7.08
		Forearm	10.00 ± 8.49
		Volar arm	12.37 ± 5.02
	104 males Fitzpatrick skin phototype I–IV	Face	5.57 ± 7.13
		Forearm	11.06 ± 7.54
		Volar arm	13.50 ± 5.75