Acne is a common skin disorder and comes in a variety of forms. The most common are whiteheads or blackheads, also known as comedones. These are pores that are filled with excessive oil (sebum) and dead skin cells. If bacteria are present, inflammation will occur. Propionibaterium acne, called P. acne causes the inflammation in the follicle. Larger lesions such as pustules, nodules or cysts may develop which can be very painful and lead to scarring if left untreated. Acne scars develop to some degree in most people who suffer from acne and these lesions can cause both physical and emotional scarring.