348 JOURi_ T .1. L 01� cos�rnTIC ... CTENCE Shaving Wax depilation 0. 0mm Day 1 Day 1 0 Day2 Day2 0mm Day9 Day9 Figure 1. :Macrophotographs from one subject of shaved and wax-depilated leg areas one day after hair removal (day 2) and eight days after hair removal (day 9) compared to condition before hair removal (day 1). Due to a good relocation of test areas after one week, the fate of single hairs can be observed (magni­ fication: 5 x). The circles show a small pigmented spot at the bottom of a hair that can be used as a permanent skin mark to relocate the test area. Irritation is seen as a red spot around a non-depilated hair (arro ·s).

IMAGE ANALYSIS AND HAIR REMOVAL EFFICACY 349 a b 80 250 !!! 60 '1S 40 20 --+-Shaving I --------waxdepilalion1 .� ---- "' � �· '" "\ ___ , ------1· --·- I 200 (,:i 150 100 50 10 10 Day Day d 2500 25 --+-Shaving � 20 ! 2000 --------wax depilation ., g 15 1500 ! 'S 1000 'S 10 --+-Shaving --a-Wax depilation 500 ...J 0 10 1 10 Day Day Figure 2. Compared to shaving, delayed reappearance of hairs after wax depilation is demonstrated by number (a), length (c) and projection area (d) of hairs. Thickness of hairs (6) increased slightly directly after both hair removal methods due to a shift in the relation of thick and thin hairs n = 10, means and 95 % confidence limits. Day 2 4 7 9 Table I Regrowth of Leg Hairs after Shaving and Wax Depilation (Group 1, n = 10) Projection area of hairs (mm2) Mean ± standard deviation CI% Shaving Depilation Shaving 13.2 ± 5.0 11.0 ± 3.6 3.6 5.2 ± 1.7 3.0 ± 1.4 1.2 7.6 ± 2.9 4.2 ± 4.8 2.1 11.4 ± 3.0 3.7 ± 1.1 2.2 14.7 ± 5.3 5.5 ± 3.0 3.8 Depilation 2.6 1.0 3.4 0.8 2.2 depilation extended the period until hairs reappeared on the skin surface compared to the shaved area, as expected. Figure 3 and Table II show the results of the projection area for Group 2, following the evolution of hair regrowth after depilation over a period of four weeks. Here it can be seen that by day 22, 21 days after depilation, hairs had regrown to their status before depilation. In contrast, shaved hairs returned to their original status about seven days after shaving (Figure 2d). For days 15 and 22, paired statistical analysis did not show significant differences in projection area compared to day 1, indicating that the regrowth of hairs returned to initial values in week 3 after depilation.