ABSTRACT
<p><b>OBJECTIVE</b>To measure the male anterior hairline (AH) and provide data for hair transplantation.</p><p><b>METHODS</b>205 males were randomly involved and divided into different age groups, as the young group( age 18-29), the middle-aged group (age 30-49) and the old group (age 50+). Their AH shape and height were measured. The data was then analyzed.</p><p><b>RESULTS</b>According to the morphological classification of AH, the linear type was most common in the young and middle-aged groups (48.40% and 37.33%), the anterior protrusion type was most common in the old group (34.80%). The mean height of AH was 6.42 cm (5.00-8.50 cm)for the median line, and there was no statistical difference between groups (P > 0.05); the mean ratio of median line AH height to facial length was 0.30 (0.22-0.37), there were significant differences between the old group against the young, or the middle-aged group (P < 0.05), and no difference between the young group and the middle-aged group (P > 0.05); the mean height of AH was 5.83 cm (3.5-8.0 cm) for the paramedian line, and there was no statistical difference between groups (P > 0.05); the mean height of AH was 8.34 cm (5.5-10.5 cm) for the lateral line, there were significant differences between the young group against the middle-aged, or the old group (P < 0.05), and no difference between the middle-aged group and the old group (P > 0.05).</p><p><b>CONCLUSIONS</b>The shape and height of AH were age-associated. The linear type is most common in the young and middle-aged groups, the anterior protrusion type is most common in the old group. The change first occurs on the lateral lines since the age of 30, and the central portion is involved since the age of 50. The older the age gets, the higher the hairline is.</p>