Dermatology is the study of skin and its diseases, and/or the branch of medicine dealing with the diagnosis of skin diseases and their treatment. A medical physical involved in dermatology is referred to as a dermatologist.
The skin is a component of the integumentary system and the largest organ on the human body. It protects us from the world around us and the substances that it contains. The skin is composed of 3 layers; the epidermis, the dermis, and the hypodermis (subcutaneous tissue). Each performing their own very important functions and jobs. Skin conditions are never pleasant and vary from shape, size, and location. Skin cancer, acne, and rashes are just a few of the very many varieties of skin conditions. Skin cancer is the most common form of human cancer. There are two common types of skin cancer: basal cell carcinoma and squamous cell carcinoma. Acne is a condition that millions suffer from daily. It is not only present in teenagers, it can appear at any age in life. Rashes are caused by skin irritation. They vary from a mild redness of the skin or a rash of small red bumps. Facial aging is a condition that all people go through. Many try to prevent or soften the aging process, but in reality no one can escape it.
The skin is the largest organ of the body. It weighs about 6 pounds. An average adult has almost 22 square feet of skin. The skin is made up of three layers: the epidermis, the dermis, and subcutaneous tissue.
- The epidermis contains 5 layers. The outer layer is called the stratum corneum. This layer of the skin is responsible for the barrier of the skin. It protects the skin from foreign invaders and substances from the outside.
- The dermis is the second layer. This layer of skin contains collagen and other substances that provide the skin with its structure.
- The subcutaneous tissue is the last layer. This layer of skin contains fat and blood vessels. It also is responsible for controlling and regulating the temperature of the skin and body.
The skin is a very complex structure that has many jobs. There are six main jobs that the skin has to perform 24 hours a day: barrier, protection, sensation, regeneration, regulating temperature, and UV protection.
- Barrier: This is self-explanatory; skin protects the body from substances entering your body.
- Protection: Skin keeps bacteria and viruses from entering the body and from harming itself.
- Sensation: Skin allows you to feel and sense the things around you.
- Regeneration: Repairs and fixes sores and wounds.
- Regulating temperature: maintains homeostasis.
- UV protection: Keeps UV rays from harming our bodies.
Disease and Disorders
Skin cancer is the most common form of human cancer. The estimate of new cases that appear yearly is one million. Skin cancer is increasing every year, which also raises more concern for this disease. Changes in appearance of the skin, like a growth or a sore that will not heal are a few signs of skin cancer. Melanoma is said to be the most serious form of skin cancer, but less common than others. It tends to spread throughout the body very quickly. There are two common types of skin cancer: basal cell carcinoma and squamous cell carcinoma. Basal cell carcinoma almost never spreads but causes damage however, by invading and damaging the tissue surrounding it. This type of cancer begins as a small, dome-shaped bump and is often covered by small, blood vessels and its appearance is usually shiny. Squamous cell carcinoma begins in the squamous cells, which are thin, flat cells. These cells are located on the surface of the skin, in the lining of the hollow organs of the body, and the passages of the respiratory and digestive tracts. The earliest signs and appearance of squamous cell carcinoma is rough, red bumps on the scalp, face, ears, and the back of hands. The people that are most likely to get skin cancer are the ones who, Spend a lot of time in the sun or sunburned, have light colored skin, hair, and eyes, have a family member with skin cancer, and those over the age of 50. 
Acne does not just occur in teenagers, but can also occur in people from ages 10 to 40. Few have acne into their 40's because they may just grow out of it. It is not uncommon to see women in their 20's who suffer from acne. Acne can appear in many different forms on the skin. For example whiteheads, blackheads, pimples ("zits"), and cysts(deep pimples). Acne and these other breakouts can occur wherever there is a good amount of oil. The oil is secreted from the sebaceous glands which are mostly on the face, chest, and back. Once a person has begun to grow into puberty, their sebaceous glands are stimulated by hormones from the adrenal glands of both boys and girls. Sebum, a natural oil, lubricates and protects the skin. In some cases, the cells that are close to the surface of the skin block openings of the sebaceous glands which cause a build-up of oil underneath leading to acne. Myths of certain substances causing acne have been told from generation to generation. The mythological factors that do no cause acne, at least on their own are: heredity, food (greasy foods), dirt (such as sweat), stress, cosmetics and hormones. However, drugs and medication, pressure (from clothing and or equipment) and occupations (ones that exposes a person to industrial products) may be factors in acne.  The treatment for acne can vary depending on the person. There are prescriptions that you can get from your doctor, and acne treatment creams and face wash. Proactiv, Neutrogena, and Clean and Clear are just a few examples of the best selling and popular acne treatment products.
Rashes are caused by skin irritation. A rash may go away with home treatment, but sometimes it may not go away because the skin may have been so irritated that medical care is needed. Rashes start usually within about 48 hours after contact with an irritating substance. Rashes vary from a mild redness of the skin or a rash of small red bumps. However, a very severe reaction may cause swelling, redness, and large blisters. Some causes can include:
- Poisonous plants (poison ivy or poison oak)
- Soaps, detergents, shampoos, perfumes, cosmetics, and lotions
- Jewelry and fabrics
- Latex and rubber
Rashes appear in many different areas depending on what your body is allergic to, some of these include:
Rashes may also appear from more serious diseases such as:
- liver disease
- kidney disease
- some types of cancer
- exposure to an insect or a parasite
- cold weather or extremely hot weather which would cause heat rash
- emotional stress(frustration or embarrassment)
If a rash occurs and other symptoms, like shortness of breath or fever, may mean there is a serious allergic reaction or infection, and medical help should be a priority.
Scarring Scarring happens only when the dermis is damaged. Acne scars are often the product of an inflame lesion. This is when the pores swell causing a break in the follicle wall. If this happens near the surface of the skin, it heals quickly. However, those deeper into the skin are the ones that cause serious lesions. The dermis is then covered in infected substances, which destroys the healthy skin tissue.  There is hope for those who do suffer from scarring. Treatments progress daily and advance moderately. A few treatment options for acne scarring are: laser treatments, chemical peels, injections, and punch techniques (which uses physical removal of the scared tissue). There are three types of this technique
- Punch Excision: This technique uses a punch biopsy tool. doctors use local anesthesia to numb the area. The tool removes the scar and its surrounding edges.
- Punch Excision with Skin Grafting: The scar is removed by a punch biopsy tool. After the removal of the scar a doctor fills the area of the skin with a skin graft of the patient's own skin.
- Punch Elevation: A biopsy tool removes the scar like the other two techniques. However, instead of a skin graft over the wound, the scar tissue is lifted up and reattached back on the person's body.
Facial Skin Aging
- Main Article: Aging
The natural aging process is a continuous cycle that usually begins in a person's mid twenties. The reason this happens and why ages appear more clearly as we age is because the collagen and elastin in the skin slows down. The elastin (the substance within the skin that allows the skin to "bounce" back) doesn't "bounce" back as strongly as it did before. Dead skin cells also tend to slow down causing the new skin cells to decrease. Though this process begins when we are still young, the signs of aging will not begin to appear until years later. Signs that you should look for in aging are:
- Fine wrinkles
- Thin and transparent skin
- Loss of underlying fat, leading to hollowed cheeks and eye sockets as well as noticeable loss of firmness on the hands and neck
- Bones shrink away from the skin due to bone loss, which causes sagging skin
- Dry skin that may itch
- Inability to sweat sufficiently to cool the skin
Genetics do play a huge role in how quickly or how slowly we age. Some lose hair when they are only in their twenties others don't have gray hairs until they are much much older. A very rare condition that cause aging quite rapidly is called Werner’s syndrome. People with this condition causes them to appear elderly around their thirties. Gray hair may also start appearing in their teens. A sad but true fact about people with this syndrome, they are expected to live until only the age of forty-six.
There are a few factors that play big roles in aging more quickly or appearing to look elderly:
- Over exposure to the sun: If out in the sun for a few hours each day without protection, over the years changes in the skin will become more apparent. Freckles, age spots, spider veins on the face, rough and leathery skin, fine wrinkles, loose skin, a blotchy complexion, and skin cancer can all come from too much sun exposure. Most scientists call this kind of aging “Photoaging” due to the suns harmful and harsh rays. This develops over a few years and the amount of how much photoaging can develop on a person depends on their color of skin and their amount of time spent out in the sun. Also, those with fair and light colored skin unfortunately develop more signs of photoaging than those with dark skin. People who live in hot climates, like Florida, start to develop some of these signs in their twenties as well as skin cancer.
- Facial Expressions: Facial expressions that people perform throughout their youth often times lead to wrinkles and fine lines. Each time we make an expression, grooves form underneath our skin, which is why we see lines appear with all facial expressions. When older, the elasticity in the skin grows weaker, creating less of a youthful appearance.
- Gravity: Gravity is always at work pulling on our bodies. The “artwork” of gravity becomes more apparent as we age.
- Sleeping positions: When resting your face on a pillow the same way for years can also lead to wrinkles. Women tend to sleep on their side and men tend to sleep with their face pressed into the pillow. Usually these are called “sleep lines.” However as we age the sleep lines never disappear. Since women tend to sleep on their side they will most likely notice wrinkles on their chin and cheeks. Since men sleep with their face in the pillow, they will notice them on their forehead. Those who sleep on their back do not develop these wrinkles since their face never touches the pillow.
- Cigarettes: These cause biochemical changes within our skin. A person who smokes 10 or more cigarettes a day for 10 years is more likely to develop wrinkled, leathery skin than a nonsmoker. Another unpleasant outcome of smoking is a yellow tint to the skin. Smoking is never a good thing; it leads to many problems inside your body as well as outside. Those who have smoke but quit, their skin tone improves. 
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