Dermatology concerns the study, research and diagnosis of normal skin and disorders of the skin. Cancers, cosmetic and aging conditions of the skin, hair, nails, fat, oral and genital membranes are all aspects of dermatology. An expert in dermatology is called a dermatologist who diagnoses, investigates, treats, and manages the conditions of children and adults with skin disease, as well as hair and nail complaints. A dermatologist is a type of doctor that diagnoses and treats conditions that affect your hair, skin, and nails. They also treat conditions that affect mucous membranes, or the delicate tissue that lines your nose, mouth, and eyelids. The Centers for Disease Control and Prevention (CDC) estimates that there are 44 million Trusted Source visits to dermatologists every year. The primary reasons for these visits include treating: