Sebaceous skin

Peel depth is determined by multiple factors including the type of acid, acid concentration, volume of acid used, and skin thickness. Additionally, the duration and aggressiveness of skin preconditioning will also affect peel penetration. Skin preconditioning can help with peel penetration by thinning the stratum corneum or by decreasing oil [sebum) production. TCA is a water-soluble agent that does not penetrate well in sebaceous skin. Thus sebum control prior to peels helps to enhance peel penetration. Alternatively phenol is Hpid soluble however, as we will cover in this chapter, the croton oil in the phenol peel solutions may play a more important role in peel depth than the phenol concentration. 

The presence of sebaceous hyperplasia and thick sebaceous skin often suggest that the patient will tolerate deeper peels. A history of oily skin suggests that more degreasing and preparation may be valuable to insure even penetration. 

Figure 15.32 Type II Fitzpatrick patients with thick sebaceous skin are often ideal candidates for deep perioral peels. In this patient treated with unoccluded Baker s solution, only the slightest depigmentation is noted associated with a shinier skin. This is the kind of patient that would be most pleased with the procedure...

Fig. 1. Schematic of the cross section of a mammal s skin. The relative size and function of the parts depend on the species and breed of the animal. For goats, where the wool or hair is sparse because it is not needed for warmth, the skin is dense to provide protection for sheep protected primarily by heavy wool, the skin contains more oil (sebaceous) glands to lubricate the wool for catde, both the hair and the heavy hide stmcture protect the animal (3).

Sheep and fur animals are protected primarily by their wool or hair. The fiber stmcture of the skin is very fine and has less strength than calfskin or other nonfur mammals. The sheepskin has a high concentration of hair foUicles and sebaceous glands. When taimed the fur skin has an open stmcture, is soft, and lacks strength relative to many other leathers. 

Chemical Acne Many chemical compounds induce skin lesions that are similar to acne. Oils, tar, creosote, and several cosmetic products induce chemical acne. These compounds induce keratinization of the sebaceous glands of the skin, obstruction of the glands, and formation of acne. Chloracne is a specific skin lesion that is induced by chemical compounds that are structurally similar to 2,5,7,8-tet-rachloro dibenzo-p-dioxin (TCDD). Chloracne is slow to heal and difficult to... 

Hautreiz, m. skin irritant skin irritation, hautreizend, a. irritating to the skin. Haut-salbe, /. sebaceous matter akin ointment. -substanz,/. hide substance, -talg. m. sebaceous matter,... 

Lanolin is a wax made in the sebaceous glands of sheep and washed out of wool with detergents. It is used in many hair- and skin-care products. 

It is still debatable whether preparation of the skin is required for deep chemical peeling. We feel that topical retin A preparations used daily for 3-6 weeks prior to the procedure may create better and more even penetration of the peeling solution in sebaceous and hyperkeratotic skins. We did not find any benefit of this regimen in thin-skinned patients. 

Phymofous irregular skin thickening due to sebaceous hyperplasia (Fig. 17.7)... 

Assess phototype, degree of sebaceous activity, skin thickness, and pigmentary abnormalities (Wood s light). 

The pilosebaceous unit of the skin consists of a hair follicle and the surrounding sebaceous glands. An initial acne lesion called a comedo forms when there is a blockage in the pilosebaceous unit.8... 

Sebum is released by the sebaceous glands and naturally maintains hair and skin hydration. An increase in androgen levels, especially during puberty, can cause an increase in the size of the sebaceous gland and the production of abnormally high levels of sebum within those glands. This excess sebum can result in plugged follicles and acne formation. 

Beyond physical barrier protection, several natural processes lead to skin surface conditions unfavorable to microbial growth. Both sebaceous and eccrine secretions are acidic, lowering the surface pH of the skin below that welcomed by most pathogens. This acid mantle (pH 5) [16] is moderately bacteriostatic. Sebum also contains a number of short-chain fungistatic and bacteriostatic fatty acids, including propanoic, butanoic, hexanoic, and heptanoic acids [17]. That the skin s surface is dry also offers a level of protection. It comes as no surprise that fungal infections and other skin infections are more prevalent in the skin s folds... 

Comedo (pi. comedones) Dermatitis Dermatitis herpetiformis Plug of dried sebum in the sebaceous duct blackhead Inflammation of the skin Dermatitis marked by grouped erythematous, papular, vesicular, pustular, or bullous lesions occurring in varied combinations... 

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