1. Caliber: referring to the actual size of the hair shaft. Coarse hair provides better results in one session than fine hair. For example, if we go from fine hair with a diameter of 40 microns to coarse hair with a diameter of 80 microns, the area covered increases TWELVE fold. Since the hair shaft is a circle the area is ∏r2 hence (3.14)(2)2= 3.14x 4≥12. Caliber is the single most important factor to consider when deciding on the number of follicular units to transplant.
Here’s some simple examples of #1 and #2:
Real life examples:
*All patients had the same amount of follicular units transplanted (2500)
2. Texture: curly, wavy, frizzy or stick straight, your hair characteristics also contribute to the amount of perceived coverage. Wavy and curly hair will cover more area than fine, straight hair. African-American hair covers a greater volume and more than compensates for the lower hair density in this race. (see above illustration)
3. Contrast: the color of the hair compared with the skin tone of the individual. Black hair looks thinner on fair skinned individuals, but thicker on someone that has a darker complexion. The less contrast, the thicker the hair will look.
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