Hair sewing is mainly caused by excessive hair loss. Whether it can be recovered mainly depends on the causes of hair loss and the subsequent maintenance. The causes of hair loss mainly include patchy baldness, seborrheic alopecia, and ringworm of the head, and so on. 1. Patchy baldness: This disease may be related to heredity, excessive mental stress, overwork, anxiety and other reasons, resulting in sudden hair loss over a period of time. Most of the patients with limited hair loss of this disease can recover completely, but if the affected area is too large, the probability of hair regeneration is smaller in all. 2. Seborrheic alopecia: mainly due to the excessive secretion of androgens in the body leading to shortening of the hair growth cycle, the hair gradually thinning and softening, resulting in alopecia areata. Generally speaking, if found early and treated in time, most of the patients are able to get improvement, which is manifested as a decrease in the amount of hair loss or an increase in the number of hairs, etc. However, if the disease develops to the late stage, the scalp is exposed and it is difficult to be restored. 3. Tinea capitis: mainly due to fungal infection caused by hair loss, itching and other conditions, in the anti-fungal infection can be cured. The appearance of hair seams to become larger is recommended to consult a doctor in a timely manner, and follow the doctor’s instructions for treatment.