Healing

How does the skin heal?

Like all organs, the skin is equipped with repair and renewal capacities that help it heal: more or less rapidly and not always true. It all depends on the extent and depth of the injury.

The skin has three superposed layers: The epidermis at the surface, below there is the dermis which is rich in nourishing blood vessels and nerves, all located within a collagen and hyaluronic acid structure. Finally, in depth, there is the hypodermis.

If the injury is superficial and does not affect the epidermis, then the skin is able to renew itself provided causes of irritation are eliminated.

When the injury is more important, deep structures of the skin may be affected and the body unleashes a different cascade of reactions:

• Blood coagulates to stop bleeding, a blood clot forms.
• Defence cells called macrophages absorb eventually present debris and microorganisms to clean the injury: It is called the cleansing phase. During this phase that may last from a few hours to 4 days, the wound exudes colourless to slightly yellow liquid, called lymph, containing cleansing and stimulating substances that favour the emergence of vessels. The healing process has begun.
• To make up for the wound-induced loss of substance, the proliferation phase sets in. A new support tissue is constituted with collagen and hyaluronic acid synthesis by cells from the dermis. New vessels are created. This tissue proliferates to the surface of the skin.
• When this tissue sufficiently fills in the wound, the epithelium of the adjacent intact skin colonizes the surface of the wound. At the end of ten days, the crust falls to reveal a scar.

This natural healing process may be compromised by different factors, either the presence of foreign bodies, important hematoma, infection, and underlying disease but also by inadequate care.

Dermatosis (dermatitis, psoriasis, vitiligo)

Dermatitis

Dermatitis is characterized by intense itching and is one of the most frequent skin diseases responsible for nearly 30% of consults in dermatology. It’s a chronic inflammatory disease of multiple origins including allergy being the main cause. It is characterized by the presence of poorly defined red plaques, sometimes associated with small transparent blisters that may converge in bubble, break, and seep then form a crust.

There are two major types of dermatitis.

Contact dermatitis

It is only observed when there is contact with substances –so called allergenic – i.e. causing an allergic reaction. These substances may vary from one person to another: medicines, hair dyes, plastic (latex gloves), metals (earrings)…the doctor will use skin tests to identify which substance causes the allergy.

Atopic dermatitis

Atopic dermatitis is determined by a hereditary predisposition to develop allergic reactions associated with a genetic abnormality which renders the skin “permeable” to some substances. This is the case of some food among infants and substances in the air among older (pollen, dust mite…).

Main localizations of dermatitis:

• cheeks
• elbows
• forehead
• knees

Atopic dermatitis progresses naturally with age:

• In infants, flare-ups are frequent and are essentially present in the cheeks and forehead;
• After the age of 2, the dermatitis become more chronic, it rather affects the skin folds (elbows, knees); as a result of scratching, the skin becomes dry and thick.
• Dermatitis declines in 85-90% of cases in adolescents and adults.

Le vieillissement cutané

La peau et ses constituants        

 Sensible, réactive, émotive quand elle rougit, la peau reflète nos émotions, notre vitalité et, avec le temps, notre âge.

Pour assurer ses multiples fonctions, en premier lieu nous protéger des coups, des blessures et des micro-organismes, notre peau est constituée de trois couches :

• L’épiderme, en surface : recouvert d’une couche cornée protectrice et truffé de terminaisons nerveuses sensorielles, il est imperméabilisé par le sébum, une substance grasse, et équipé de cellules productrices de mélanine, le pigment qui protège du soleil.
• Le derme, situé en dessous de l’épiderme : structure de soutien, il est doté d’une armature de fibres de collagène et d’élastine baignant dans un gel de protéoglycannes. Il contient toutes les structures nécessaires au fonctionnement de la peau : vaisseaux sanguins, follicules pileux, glandes sudorales ou sudoripares, glandes sébacées productrices de sébum et les cellules fibroblastes sécrétant l’armature fibreuse ainsi que l’acide hyaluronique.
• L’hypoderme, en profondeur: c’est un isolant thermique disposant de réserves énergétiques en graisses.

Les composants essentiels pour la tonicité de la peau

• Le collagène du derme : les fibres de collagène, reliées par des filaments d’élastine, constituent une véritable armature pour la peau et lui permet de résister aux coups et aux chocs.
  • Il assure tonicité et résistance 

• L’acide hyaluronique : inséré entre les fibres de collagène, il possède d’excellentes propriétés hydratantes en retenant jusqu’à 1000 fois son poids en eau et crée ainsi un « matelas » hydraté et rebondi.
  •  Il procure souplesse et hydratation 
• Les anti-oxydants, présents dans toutes les cellules de la peau : ils maintiennent l’intégrité de la peau en neutralisant les radicaux libres. Les radicaux libres sont des composés toxiques issus du métabolisme des cellules et des agressions extérieures (soleil, infections, inflammations …). S’ils ne sont pas neutralisés, ils détruisent les structures alentour et l’on estime aujourd’hui qu’ils sont les principaux responsables du vieillissement.

Pour piéger ces radicaux libres, notre alimentation nous procure des antioxydants naturels. Ils constituent la principale défense contre le vieillissement