Two packages of gauze. One 10 cm by 4.1 m. The other 5 by 5 cm.Three types of gauze Depiction of a<unk> on a face from a painting from 1490 Historically,<unk>  were made of a piece of material, usually a cloth, but the use of cobwebs, dung, leaves and honey have also been described. However, modern<unk>  include dry or impregnated gauze, plastic films, gels, foams, hydrocolloids, alginates, hydrogels, and polysaccharide pastes, granules and beads. They all provide different physical environments suited to different wounds: * Absorption of exudate, to regulate the moisture level surrounding the wound- for example, dry gauzes absorb exudate strongly, drying the wound, hydrocolloids maintain a moist environment and film<unk>  do not absorb exudate; * Gas permeability and exchange, especially with regard to oxygen and water vapour; * Maintaining the optimum temperature to encourage healing; * Mechanically debriding a wound to remove slough. * Pressure<unk>  are commonly used to treat burns and after skin grafts. They apply pressure and prevent fluids from collecting in the tissue.<unk>  can also regulate the chemical environment of a wound, usually with the aim of preventing infection by the impregnation of topical antiseptic chemicals. Commonly used antiseptics include povidone-iodine, boracic lint<unk>  or historically castor oil. Antibiotics are also often used with<unk>  to prevent bacterial infection. Medical grade honey is another antiseptic option, and there is moderate evidence that honey<unk>  are more effective than common antiseptic and gauze for healing infected post-operative wounds. Bioelectric<unk>  can be effective in attacking certain antibiotic-resistant bacteria and speeding up the healing process.<unk>  are also often impregnated with analgesics to reduce pain. The physical features of a<unk> can impact the efficacy of such topical medications. Occlusive<unk> , made from substances impervious to moisture such as plastic or latex, can be used to increase their rate of absorption into the skin.<unk>  are usually secured with adhesive tape and/or a bandage. Many<unk>  today are produced as an "island" surrounded by an adhesive backing, ready for immediate application – these are known as island<unk> . Passive products Generally, these products are indicated for only superficial, clean, and dry wounds with minimal exudates. They can also be used as secondary<unk>  (additional<unk>  to secure the primary<unk> in place or to absorb additional discharge from the wound). Examples are: Gauze, lint, adhesive bandage (plasters), and cotton wool. The main aim is to protect the wound from bacterial contamination. They are also used for secondary<unk>  Gauze<unk> is made up of woven or non-woven fibres of cotton, rayon, and polyester. Gauze<unk> are capable of absorbing discharge from wound but requires frequent changing. Excessive wound discharge would cause the gauze to adhere to the wound, thus causes pain when trying to remove the gauze from the wound. Bandages are made up of cotton wool, cellulose, or polyamide materials. Cotton bandages can act as a secondary<unk> while compression bandages provides good compressions for venous ulcers. On the other hand, tulle gras<unk> which is impregnated with paraffin oil is indicated for superficial clean wound. Interactive products Several types of interactive products are: semi-permeable film<unk> , semi-permeable foam<unk> , hydrogel<unk> , hydrocolloid<unk> , and alginate<unk> . Apart from preventing bacteria contamination of the wound, they keep the wound environment moist in order to promote healing. Semi-permeable film<unk>  This<unk> is a transparent film made up of polyurethane. It allows the movement of water vapor, oxygen, and carbon dioxide into and out of the<unk>  It also plays an additional role in autolytic debridement (removal of dead tissue) which is less painful when compared to manual wound debridement inside the operating theater. It is highly elastic and flexible, thus is closely adhered to the skin. As the<unk> is transparent, wound inspection is possible without removing the<unk>  Due to the limited absorption capacity, such<unk> is only used in superficial wounds with low amount of discharge. Semi-permeable foam<unk>  This<unk> is made up of foam with hydrophilic (attracted to water) properties and outer layer of hydrophobic (repelled from water) properties with adhesive borders. The hydrophobic layer protects the wound from the outside fluid contamination. Meanwhile, the inner hydrophilic layer is able to absorb moderate amount of discharge from the wound. Therefore, this type of<unk> is useful for wound with high amount of discharge and for wound with granulation tissue. Secondary<unk>  are not required. However, it requires frequent changing and is not suitable for dry wounds. Silicone is a common material that make up the foam. The foam is able to mold according to the shape of the wound. Hydrogel<unk>  This<unk> is made up of synthetic polymers such as methacrylate and polyvinyl pyrrolidine. It has high water content, thus provides moisture and cooling effect for the wound. The<unk> is easy to remove from the wound without causing any damage. The<unk> is also non-irritant. Therefore, it is used for dry necrotic wound, necrotic wound, pressure ulcers, and burn wound. It is not suitable for wounds with heavy discharge and infected wounds. Hydrocolloid<unk>  This type of<unk> contains two layers: inner colloidal layer and outer waterproof layer. It contains gel forming agents such as carboxymethylcellulose, gelatin and pectin. When the<unk> is in contact with the wound, the wound discharge are retained to form gel which provides moist environment for wound healing. It protects the wound from bacterial contamination, absorbs wound discharge, and digests necrotic tissues. It is mostly use as secondary<unk>  However, it is not used in wound with high discharge and neuropathic ulcers. Alginate<unk>  This type of<unk> is made up of either sodium or calcium salt of alginic acid. This<unk> can absorb high amount of discharge from a wound. Ions present in the<unk> can interact with blood to produce a film that protects the wound from bacterial contamination. However, this<unk> is not suitable for dry wounds, third degree burn wound, and deep wounds with exposed bone. It also requires secondary<unk> because wounds can quickly dry up with alginate<unk>  Bioactive products Advancements in understanding of wounds have commanded biomedical innovations in the treatment of acute, chronic, and other types of wounds. Many biologics, skin substitutes, biomembranes and scaffolds have been developed to facilitate wound healing through various mechanisms.
Dressing 
Skin disinfection
Field dressing 
Surgical suture
Urination
Skin care
Tooth polishing
Hand sanitizer