Hair loss has many causes, including genetics, inflammation, infection, illness, poor nutrition, extreme hairstyles, physical or emotional shock, medications and medical treatments. Most types of hair loss are temporary, meaning the hair grows back after the issue causing the loss has been resolved and a considerable amount of time has passed for healing. Two types of hair loss are considered permanent: androgenetic alopecia and cicatricial alopecia. Androgenetic alopecia is genetic, pattern baldness. Cicatricial alopecia occurs because of inflammation scarring. Some temporary forms of hair loss can lead to cicatricial alopecia if left untreated.
The first sign of male-pattern baldness, or androgenetic alopecia in males, involves thinning at the top sides of the front hairline and the formation of a widow's peak, or M-shaped hairline. Young men in their teens and early 20s can start seeing signs of this form of permanent hair loss. However, men in their 30s are more susceptible to developing the condition. Those who start losing their hair early tend to lose more hair than those who start later in life.
Thinning on Top of Head
Androgenetic alopecia affects women differently than men. While men develop a receding hairline and widow's peak, women tend to have thinning on top of the head while the front hairline remains intact. Men also thin on top of the head and in the crown as the loss progresses. Both men and women continue to grow thick hair at the nape of the neck and over the ears. Even though women rarely go completely bald, the hair loss associated with androgenetic alopecia is considered permanent.
Cicatricial alopecia has many causes. Inflammation caused by trauma, autoimmune disorders, genetics, infection, lupus and follicle degeneration attacks stem cells located at the base of hair follicles, according to American Family Physician. Stem-cell failure renders follicles unable to produce new hair. Hair loss occurs while follicles are inflamed. Some people may experience itching and pain along with the condition. The skin appears smooth and without follicles after the inflammation subsides.
Absence of New Growth
The absence of new growth after six months to a year points to permanent hair loss. Skin without new growth appears smooth and shiny. The presence of fuzz or downy hairs indicates new growth and possibilities for full recovery.