Fissur

Fissur is a term used in several languages to denote a narrow opening, crack, or groove in a solid substance. In English the corresponding term is fissure, from Latin fissura, meaning a split. The word is used across disciplines to describe natural or pathologic splits.

In geology, a fissure is a natural crack or opening in rock or earth caused by tectonic stress, cooling, or weathering. Fissures may be linear, uneven, and sometimes become conduits for fluids; they may host mineral veins or serve as joints or faults in larger fracture systems.

In medicine and anatomy, fissures refer to small clefts or splits in tissues. Anal fissures are painful tears in the anoderm at the opening of the anus and are often associated with constipation, childbirth, or inflammatory bowel disease. Skin fissures occur in dry or thickened skin, sometimes in eczema, and can be painful and prone to infection; treatment emphasizes moisture, barrier care, and, if needed, topical medication. In dentistry, fissures describe grooves on the chewing surfaces of teeth that can harbor plaque and decay; sealing fissures or restoring them prevents caries.

See also: fissure, crack, joint, groove.