Dense small particles on the face can be seen in flat warts, atopic dermatitis, perifollicular moss and eczema and other diseases, in the treatment of laser therapy, cryotherapy, anti-allergy, dissolve keratin and stop itching and other ways to solve. 1. flat warts: a disease caused by skin infection with human papillomavirus, in the treatment of laser therapy and cryotherapy, but also through the topical application of retinoic acid cream, imiquimod ointment and other drugs to improve the symptoms. 2. Allergic dermatitis, in the treatment is mainly symptomatic for some anti-allergic drugs, such as topical Dinaid cream, oral cetirizine hydrochloride capsules and so on. 3. perifollicular moss, in the treatment mainly refers to some of the keratolytic drugs, such as topical Vitamin A cream, oral isotretinoin soft capsule and so on. 4. Eczema belongs to a kind of inflammatory disease, easy to be transformed into chronic eczema due to repeated attacks, in the treatment can be given to some anti-allergic treatment of medication, such as dandrol ointment and so on. Due to the complexity of the cause of the disease, the specific circumstances need to ask the doctor for an interview.