The inferior nasal concha (inferior turbinated bone or inferior turbinal/turbinate) is one of the three paired

nasal concha In anatomy, a nasal concha (), plural conchae (), also called a nasal turbinate or turbinal, is a long, narrow, curled shelf of bone that protrudes into the breathing passage of the nose in humans and various animals. The conchae are shaped like ...

e in the

nose A nose is a protuberance in vertebrates that houses the nostrils, or nares, which receive and expel air for respiration alongside the mouth. Behind the nose are the olfactory mucosa and the sinuses. Behind the nasal cavity, air next passes th ...

. It extends horizontally along the lateral wall of the

nasal cavity The nasal cavity is a large, air-filled space above and behind the nose in the middle of the face. The nasal septum divides the cavity into two cavities, also known as fossae. Each cavity is the continuation of one of the two nostrils. The nasal c ...

and consists of a

lamina Lamina may refer to: Science and technology * Planar lamina, a two-dimensional planar closed surface with mass and density, in mathematics * Laminar flow, (or streamline flow) occurs when a fluid flows in parallel layers, with no disruption betwee ...

of spongy

bone A bone is a Stiffness, rigid Organ (biology), organ that constitutes part of the skeleton in most vertebrate animals. Bones protect the various other organs of the body, produce red blood cell, red and white blood cells, store minerals, provid ...

, curled upon itself like a scroll, (''turbinate'' meaning inverted cone). The inferior nasal conchae are considered a pair of facial bones. As the air passes through the turbinates, the air is churned against these mucosa-lined bones in order to receive warmth, moisture and cleansing. Superior to inferior nasal concha are the

middle nasal concha The medial surface of the labyrinth of ethmoid consists of a thin lamella, which descends from the under surface of the cribriform plate, and ends below in a free, convoluted margin, the middle nasal concha (middle nasal turbinate). It is rough, a ...

and

superior nasal concha The superior nasal concha is a small, curved plate of bone representing a medial bony process of the labyrinth of the ethmoid bone. The superior nasal concha forms the roof of the superior nasal meatus. Anatomy Anatomical relations The super ...

which both arise from the

ethmoid bone The ethmoid bone (; from grc, ἡθμός, hēthmós, sieve) is an unpaired bone in the skull that separates the nasal cavity from the brain. It is located at the roof of the nose, between the two orbits. The cubical bone is lightweight due to a ...

, of the cranial portion of the skull. Hence, these two are considered as a part of the cranial bones. It has two surfaces, two borders, and two extremities.

Structure

Surfaces

The medial surface is

convex Convex or convexity may refer to: Science and technology * Convex lens, in optics Mathematics * Convex set, containing the whole line segment that joins points ** Convex polygon, a polygon which encloses a convex set of points ** Convex polytope ...

, perforated by numerous apertures, and traversed by longitudinal grooves for the lodgement of vessels. The lateral surface is

concave Concave or concavity may refer to: Science and technology * Concave lens * Concave mirror Mathematics * Concave function, the negative of a convex function * Concave polygon, a polygon which is not convex * Concave set * The concavity In ca ...

, and forms part of the

inferior meatus In anatomy, the term nasal meatus can refer to any of the three meatuses (passages) through the skulls nasal cavity: the superior meatus (''meatus nasi superior''), middle meatus (''meatus nasi medius''), and inferior meatus (''meatus nasi inferio ...

Borders

Its upper border is thin, irregular, and connected to various bones along the lateral wall of the nasal cavity. It may be divided into three portions: of these, * the ''anterior'' articulates with the conchal crest of the

maxilla The maxilla (plural: ''maxillae'' ) in vertebrates is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The t ...

; * the ''posterior'' with the conchal crest of the

palatine A palatine or palatinus (in Latin; plural ''palatini''; cf. derivative spellings below) is a high-level official attached to imperial or royal courts in Europe since Roman times.

; * the ''middle'' portion presents three well-marked processes, which vary much in their size and form. ** Of these, the anterior or

lacrimal process The term Lacrimal or lachrymal, may refer to: Anatomy * Lacrimal apparatus * Lacrimal artery * Lacrimal bone * Lacrimal canaliculi (singular: canaliculus), also known as ''Lacrimal ducts'' * Lacrimal fossa (disambiguation) * Lacrimal fluid, see ...

is small and pointed and is situated at the junction of the anterior fourth with the posterior three-fourths of the bone: it articulates, by its apex, with the descending process of the

lacrimal bone The lacrimal bone is a small and fragile bone of the facial skeleton; it is roughly the size of the little fingernail. It is situated at the front part of the medial wall of the orbit. It has two surfaces and four borders. Several bony landmarks of ...

, and, by its margins, with the groove on the back of the frontal process of the maxilla, and thus assists in forming the canal for the

nasolacrimal duct The nasolacrimal duct (also called the tear duct) carries tears from the lacrimal sac of the eye into the nasal cavity. The duct begins in the eye socket between the maxillary and lacrimal bones, from where it passes downwards and backwards. The ...

. ** Behind this process a broad, thin plate, the

ethmoidal process Behind the lacrimal process of the inferior nasal conchae lies a broad, thin plate, the ethmoidal process, which ascends to join the uncinate process of the ethmoid; from its lower border a thin lamina, the maxillary process, curves downward an ...

, ascends to join the uncinate process of the ethmoid; from its lower border a thin lamina, the maxillary process, curves downward and lateralward; it articulates with the maxilla and forms a part of the medial wall of the

maxillary sinus The pyramid-shaped maxillary sinus (or antrum of Highmore) is the largest of the paranasal sinuses, and drains into the middle meatus of the nose through the osteomeatal complex.Human Anatomy, Jacobs, Elsevier, 2008, page 209-210 Structure It is ...

. The inferior border is free, thick, and cellular in structure, more especially in the middle of the bone.

Extremities

Both extremities are more or less pointed, the posterior being the more tapering.

Development

The inferior nasal concha is ossified from a single center, which appears about the fifth month of fetal life in the lateral wall of the

cartilaginous nasal capsule Cartilage is a resilient and smooth type of connective tissue. In tetrapods, it covers and protects the ends of long bones at the joints as articular cartilage, and is a structural component of many body parts including the rib cage, the neck and ...

Additional images

File:Gray171.png, Right inferior nasal concha. Medial surface. File:Gray172.png, Right inferior nasal concha. Lateral surface. File:Slide2hal.JPG, Human skull. Inferior nasal concha.

References

External links

* * {{Authority control Bones of the head and neck