A paper cut occurs when a piece of

paper Paper is a thin sheet material produced by mechanically or chemically processing cellulose fibres derived from wood, rags, grasses or other vegetable sources in water, draining the water through fine mesh leaving the fibre evenly distributed ...

or other thin, sharp material slices a person's

skin Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation. Other cuticle, animal coverings, such as the arthropod exoskeleton, have diffe ...

, often the upper part of the

finger A finger is a limb of the body and a type of digit, an organ of manipulation and sensation found in the hands of most of the Tetrapods, so also with humans and other primates. Most land vertebrates have five fingers ( Pentadactyly). Chambers ...

, and often the index finger. Notably, "paper" cuts can also be caused by other thin, stiff, and abrasive materials other than just paper. Paper cuts can be highly painful, even though they may bleed very little, if at all. Although a loose sheet of paper is usually too soft to cut, it can be very thin (sometimes as thin as a razor edge), thus being able to exert high levels of

pressure Pressure (symbol: ''p'' or ''P'') is the force applied perpendicular to the surface of an object per unit area over which that force is distributed. Gauge pressure (also spelled ''gage'' pressure)The preferred spelling varies by country and e ...

, enough to cause a cut. Paper cuts are most often caused by paper sheets that are strongly fastened together (such as brand new sheet of paper out of a

ream Ream may refer to: * Paper ream, unit of 500 sheets of paper * Ream (surname) * Reamer, tool used to widen a hole * Ream, West Virginia * Ream, the name of Rama in the Khmer version of the Ramayana, the Reamker * Ream National Park, a national pa ...

), because one single sheet might be dislocated from the rest. Thus all the other sheets are holding this dislocated sheet in position, making it stiff enough to act as a razor. Paper cuts can be painful as they can stimulate a large number of skin surface nociceptors (pain receptors) in a very small area of the skin. Because the shallow cut does not bleed as much, the pain receptors are left open to the air, causing continued pain. This is exacerbated by irritation caused by the fibers in the paper itself, which may be coated in chemicals such as

bleach Bleach is the generic name for any chemical product that is used industrially or domestically to remove color (whitening) from a fabric or fiber or to clean or to remove stains in a process called bleaching. It often refers specifically, to ...

. Additionally, most paper cuts occur in the fingers, which have a greater concentration of

sensory receptor Sensory neurons, also known as afferent neurons, are neurons in the nervous system, that convert a specific type of stimulus, via their receptors, into action potentials or graded potentials. This process is called sensory transduction. The cell ...

s than the rest of the body.

References

External links

A Moment of Science: Paper Cuts

Skin conditions resulting from physical factors {{dermatology-stub